oxygenation new

8/2/2019 Oxygenation New

http://slidepdf.com/reader/full/oxygenation-new 1/52

ACUTE RESPIRATORY DISORDERS

What is the purpose of the nose?

The purpose of the nose is to warm, clean, and humidify the air you breathe aswell as help you to smell and taste. A normal person will produce about two

quarts of fluid each day (mucus), which aids in keeping the respiratory tract clean

and moist. Tiny microscopic hairs (cilia) line the surfaces of the nasal cavity,

helping to brush away particles. Eventually the mucus blanket is moved to the

back of the throat where it is unconsciously swallowed. This entire process is

closely regulated by several body systems.

Structurally, the nose is separated into two passageways (left and right nostrils)

by a structure called the septum. Protruding into each breathing passage arebony projections, called turbinates, which help to increase the surface area of the

inside of the nose. There are three turbinates on each side of the nose (inferior or

lower turbinates, middle turbinates, superior or upper turbinates). The sinuses

are four paired, air-filled chambers which empty into the nasal cavity. Their

purpose is not really known, but may help to lighten the skull, reducing its weight.



What are rhinitis and post-nasal drip?

Rhinitis is a very common condition and has many different causes. Basically,

rhinitis may be defined as inflammation of the inner lining of the nose. More

specifically speaking, it may be defined by the presence of one or more of the

following symptoms:

Rhinorrhea (runny nose)

Nasal itching

Nasal congestion

Sneezing

http://www.medicinenet.com/script/main/art.asp?articlekey=64254






Post-nasal drip is mucus accumulation in the back of the nose and throat

leading to, or giving the sensation of, mucus dripping downward from the back of

the nose. One of the most common characteristics of chronic rhinitis is post-nasal

drip. Post-nasal drip may lead to chronic sore throat or chronic cough. Post-nasal

drip can be caused by excessive or thick secretions, or impairment in the normal

clearance of mucus from the nose and throat.

What causes rhinitis?

Rhinitis has many possible causes. Rhinitis can be either acute or chronic.

Allergic rhinitis is a very common cause of rhinitis. It is caused by allergies and

is characterized by an itchy/runny nose, sneezing, and nasal congestion. Other

allergic symptoms include:

itchy ears and throat,

Eustachian tube problems (the tube connecting the inner ear to the back of

the throat),

red/watery eyes,

cough,

fatigue/loss of concentration/lack of energy from loss of sleep, and

headaches or facial tenderness.

People with allergic rhinitis also have a higher incidence of asthma and eczema,

which are also mainly allergic in origin.

Seasonal allergic rhinitis (hay fever) is usually caused by pollen in the air, and

sensitive patients have symptoms during peak times during the year.

Perennial allergic rhinitis, a type of chronic rhinitis is a year-round problem,

and is often caused by indoor allergens(particles that cause allergies), such as

dust and animal dander in addition to pollens that may exist at the time.

Symptoms tend to occur regardless of the time of the year.









































s rhinitis always related to allergies?

No, rhinitis may have many causes other than allergies. Some of these other

types of rhinitis are listed below.

Non-allergic rhinitis occurs in those patients in whom an allergic or other

causes of rhinitis cannot be identified. Non-allergic rhinitis may be further divided

into three types;

1. vasomotor rhinitis,

2. gustatory rhinitis, and

3. non-allergic rhinitis with nasal eosinophilia syndrome (NARES).

These conditions may not have the other allergic manifestations such as, itchyand runny eyes and are also more persistent and less seasonal.

Vasomotor rhinitis is thought to occur because of abnormal regulation of

nasal blood flow and may be induced by temperature fluctuations in the

environment such as, cold or dry air, or irritants such as:

o air pollution,

o smog,

o tobacco smoke,

o car exhaust, or

o strong odors such as, detergents or fragrances.

Gustatory rhinitis may presents predominantly as runny nose (rhinorrhea)

related to consumption of hot or spicy food.

Non-allergic rhinitis with nasal eosinophilia syndrome (NARES) is

characterized by a clear nasal discharge. The nasal discharge is found to

have eosinophils (allergic cell type), although the patient may not have any

other evidence of allergy by skin testing or history or symptoms.

Occupational rhinitis may arise from exposure to irritants at a person's

workplace with improvement of symptoms after the person leaves the workplace.










Other causes of rhinitis may be related to:

pregnancy,

certain medications (oral contraceptives,

some blood pressure medications,

some anxiety medications,

some erectile dysfunction medications,

and some anti-inflammatory medications), or

some nasal structural abnormalities (deviated septum, perforated septum,

tumors, nasal polyps, or foreign bodies).

Infections, mostly viral, are a common cause of rhinitis. Viral rhinitis is usually

not chronic and may resolve by itself.


























Sometimes rhinitis may be related to other generalized medical conditions such

as:

acid reflux disease (GERD),

Wegener's granulomatosis,

sarcoidosis,

cystic fibrosis, and

other less common conditions.

What conditions cause an abnormal production of nasal

secretions?

The following conditions are often associated with increased nasal drainage.

Also, it would not be unusual to have more than one factor involved in a

particular individual.

The following may cause an increase in thin secretions:

viruses

allergies

cold temperatures

certain foods or spices

pregnancy or hormonal changes

drug side-effects (particularly certainhigh blood pressure medications)

structural problems (deviated septum, large turbinates)

vasomotor rhinitis (an abnormal regulatory problem with the nose)


















Decreasing the fluid content of the mucus usually thickens the secretions leading

to the impression of increased mucus. The following may cause thickened

secretions:

low humidity

sinus or nasal infections

foreign bodies (especially if the drainage is from one side)

environmental irritants (tobacco smoke, smog)

structural problems (deviated septum, enlarged turbinates, enlarged

adenoids)

advanced age - mucus membrane lining the nose can shrink with age leading

to a reduced volume of secretions that are thicker

hormonal problems

drug side-effects (antihistamines)

What conditions cause an impaired clearance of nasal

secretions?

Swallowing problems can make it difficult to clear normal secretions. This may

result in the accumulation of material in the throat, which can spill into the voice

box, causing hoarseness, throat clearing, or cough. The following factors can

contribute to swallowing problems:

Advancing age: This will lead to decreased strength and coordination in

swallowing.

Stress: Stress leads to muscle spasm or "lump in throat." Also a nervous

habit of frequent throat clearing will make the situation worse.

Narrowing of the throat due to tumors or other conditions: This will impair

the passage of food.
















Gastroesophageal reflux (GERD)

Nerve or muscle disorders: (stroke, and muscle diseases, etc.)

How can chronic rhinitis and post-nasal drip be treated?

The treatment is generally directed towards the underlying cause.

Identifying and avoiding allergens

An allergy is an exaggerated "normal body" inflammatory response to an outside

substance. These substances that cause allergies are called allergens, and

typically include:

pollen,

mold,

animal dander (cats and dogs),

house dust,

dust mites and cockroaches, and

some foods.The best treatment is avoidance of these allergens, but in many cases this may

be very difficult if not impossible. Some helpful suggestions include:

Use a pollen mask when mowing the grass or cleaning the house;

install an air purifier or at least change the air filters monthly in heating and air

conditioning systems;

use cotton or synthetic materials such as Dacron in pillows and bedding;

enclose mattress in plastic;

consider using a humidifier;

keep windows closed during high pollen times;


















eliminate house plants; and bathe pets frequently or even give away dander-

producing pets.

Avoidance of nasal irritants: Nasal irritants usually do not lead to the typical

immune response seen with classical allergies, but nevertheless they can mimicor make allergies worse, as in vasomotor rhinitis. Examples of these irritants

include cigarette smoke, perfume, aerosol sprays, smoke, smog and car exhaust.

Identifying the possible allergens may be just as hard as avoiding them. In some,

this may be identified by a very careful history taken by their physician. Details of

the patient's possible exposure to allergens or irritant at home or the workplace

may give some clues. In others, even a very detailed history may not reveal a

possible trigger. Therefore, a consultation with an allergy specialist (allergy and

immunologist) may be prudent. The allergy doctor may perform some simple skintests to try to identify common environmental allergies.

What medications can be used to treat rhinitis and post-nasal

drip?

In addition to measures noted above, medications may also be used for the

treatment of rhinitis and post-nasal drip.

For allergic rhinitis and post-nasal drip many medications are used.

Steroid nasal sprays

The experts recommend using intra-nasal glucocorticoids (steroid sprays applied

directly into the nose) as the first line of treatment. Steroids are known to be

potent anti-inflammatory and anti-allergic agents and they are known to relieve

most of the associated symptoms of runny and itchy nose, nasal congestion,

sneezing, and post-nasal drip.

Their use must be monitored and tapered by the prescribing physician as long-term use may have significant side effects. Examples of the nasal steroids

include:

beclomethasone (Beconase),

flunisolide (Nasarel),









budesonide (Rhinocort),

fluticasone propionate (Flonase),

mometasone furoate (Nasonex), and

fluticasone furoate (Veramyst).

These are generally used once or twice daily. It is recommended to tilt the head

forward during the administration to avoid from spraying the back of the throat

instead of the nose.

Oral steroids

These drugs

[prednisone, methylprednisolone (Medrol), hydrocortisone(Hydrocortone, Cortef)]

are highly effective in allergic patients; however there is a potential for serious

side effects when used for extended periods. They are best used for the short-

term management of allergic problems, and a physician must always monitor

their use. These are reserved only for very severe cases that do not respond to

the usual treatment with nasal steroids and antihistamines.

Antihistamines

Allergy medications, such as antihistamines, are also frequently used to allergic

rhinitis and post-nasal drip. These are generally used as the second line of

treatment after the nasal steroids or in combination with them. Histamines are

naturally occurring chemicals released in response to an exposure to an allergen,

which are responsible for the congestion, sneezing, and runny nose typical of an

allergic reaction. Antihistamines are drugs that block the histamine reaction.

These medications work best when given prior to exposure.

Antihistamines can be divided into two groups:

1. Sedating, or first generation [diphenhydramine (Benadryl), chlorpheniramine

(Chlor-Trimeton), clemastine (Tavist)]. Sedating antihistamines should be

avoided in those patients who need to drive or use dangerous equipment.







































2. Non-sedating or second generation [loratadine (Claritin), cetirizine(Zyrtec)].

Non-sedating antihistamines can have serious drug interactions. Most of

these are found over the counter.

There is also a nasal antihistamine preparation that has been shown to be veryeffective in treating allergic rhinitis, called azelastine nasal (Astelin).

Decongestant sprays

Examples of decongestant sprays include:

oxymetazoline (Afrin), and

phenylephrine (Neo-Synephrine)

Decongestant sprays quickly reduce swelling of nasal tissues by shrinking the

blood vessels. They improve breathing and drainage over the short-term.

Unfortunately, if they are used for more than a few days they can become highly

addictive (rhinitis medicamentosa). Long-term use can lead to serious damage.

Therefore, their use should limited to only 3 to 7 days.

Oral decongestants

Oral decongestants temporarily reduce swelling of sinus and nasal tissues

leading to an improvement of breathing and a decrease in obstruction. They may

also stimulate the heart and raise the blood pressure and should be avoided by

patients who have high blood pressure, heart irregularities,glaucoma, thyroid

problems, or difficulty in urination. The most common decongestant

is pseudoephedrine (Sudafed).

Cromolyn sodium (Nasalcrom)

Cromolyn sodium (Nasalcrom) is a spray helps to stabilize allergy cells (mast

cells) by preventing release of allergy mediators, like histamine. They are most

effective if used before the start of allergy season or prior to exposure to a known

allergen.

Montelukast (Singulair)








































Montelukast (Singulair) is an agent that acts similar to antihistamine, although it

is involved in another pathway in allergic response. It has been shown to be less

beneficial than the steroid nasal sprays, but equally as effective as some of the

antihistamines. It may be useful in patients who do not wish to use nasal sprays

or those who have co-existing asthma.

Ipratropium (Atrovent nasal)

Ipratropium (Atrovent nasal) is used as a nasal spray and helps to control nasal

drainage mediated by neural pathways. It will not treat an allergy, but it does

decrease nasal drainage.

Mucus thinning agents

Mucus thinning agents are utilized to make secretions thinner and less sticky.

They help to prevent pooling of secretions in the back of the nose and throat

where they often cause choking. The thinner secretions pass more

easily. Guaifenesin (Humibid, Fenesin, Organidin) is a commonly used

formulation. If a rash develops or there is swelling of the salivary glands, they

should be discontinued. Inadequate fluid intake will also thicken secretions.

Increasing the amount of water consumed, and eliminatingcaffeine from the diet

and the use of diuretics are also helpful.

Allergy shots (Immunotherapy)

Allergy shots interfere with the allergic response. After identification of an

allergen, small amounts are given back to the sensitive patient. Over time the

patient will develop blocking antibodies to the allergen, and they become less

sensitive and less reactive to the substance causing allergic symptoms.

Combinations

These drugs are made up of one or more anti-allergy medications. They areusually a combination of an antihistamine and a decongestant. Other common

combinations include mucus thinning agents, anti-cough

agents,aspirin, ibuprofen (Advil), or acetaminophen (Tylenol). They help to

simplify dosing and often will work either together for even more benefit or have

counteracting side effects that eliminate or reduce total side effects.




































What can be used to treat non-allergic rhinitis?

Treatment of non-allergic rhinitis is similar to the treatment of allergic rhinitis.

Steroid nasal sprays and nasal antihistamines [azelastine (Astelin)] as described

in more detail in the previous section, are the main stray of therapy for non-

allergic rhinitis. Combination therapy using steroid nasal spray and nasal

antihistamine together has been shown to be more beneficial.

The other therapies, such as ipratropium (Atrovent) and decongestants, may also

be used in patients who continue to have symptoms despite proper therapy with

nasal steroids and nasal antihistamines.

Does salt water have any role in the treatment of rhinitis and

post-nasal drip?

Irrigating the nose with salt water is very useful therapy for non-allergic rhinitis

and especially beneficial for treating post-nasal drip.

Nasal irrigation utilizing a buffered hypertonic saline solution (salt water) helps to

reduce swollen and congested nasal and sinus tissues. In addition, it washes out

thickened nasal secretions, irritants (smog, pollens, etc.), bacteria, and crusts

from the nose and sinuses. Non-prescription nasal sprays (Ocean spray, Ayr,

Nasal) can be used frequently, and are very convenient to use.

Nasal irrigation can be done several times per day.

Nasal irrigation is frequently performed with a syringe or a Water Pik device

(the attachment is purchased separately).

The irrigating solution can be made by adding two to three heaping teaspoons

of non-iodized (does not sting) salt to one pint of room temperature water. It is

best to use Morton Coarse Kosher Salt or Springfield plain salt because table

salt may have unwanted additives. To this solution, add one teaspoon of

baking soda.

Store at room temperature, and always mix the solution before each use.



If the solution stings, use less salt.

In the beginning, or for children, it is best to start with a weaker salt mixture. It

is not unusual to initially have a mild burning sensation the first few times you

irrigate.

While irrigating the nose, it is best to stand over the sink and irrigate each

side of your nose separately. Aim the stream toward the back of your head,

not at the top of your head.

For young children, the salt water can be put into a small spray container,

which can be squirted many times into each side of the nose.

What are other options for the treatment of rhinitis andpost-nasal drip?

Treatment can also be directed towards specific causes of rhinitis and

post-nasal drip as outlined below.

Treatment of infection

The most common nasal infection is a viral infection known as

"the common cold." The virus causes swelling of the nasal membranes and

production of thick clear mucus. Symptoms usually last several days. If "a

cold" goes on for many days and is associated with yellow or green

drainage, it may have become secondarily infected by bacteria. Sinus

blockage can lead to acute or chronic sinusitis which can be characterized

by nasal congestion, thick mucus, and facial or dental pain. Prompt and

aggressive treatment of infection by your physician, with antibiotics, along

with supplemental medications, or in some cases surgery, will help to re-

establish the normal drainage pathways.

Reflux Medications

For rhinitis that is thought to be related to acid reflux disease, antacids

(Maalox,Mylanta) can help to neutralize acid contents, whereas other

medications

[cimetidine (Tagamet), famotidine (Pepcid),omeprazole (Prilosec)] can






























decrease stomach acid production. Non-pharmacological treatments

include avoiding late evening meals and snacks and the elimination of

alcohol and caffeine. Elevating the head of the bed may help to decrease

reflux during sleep.

Surgery

Structural problems with the nose and sinuses may ultimately require

surgical correction. Obviously, this should be done only after more

conservative measures have been tried and failed. Surgery is not a

replacement for good allergy control and treatment. Septal deviation,

septal spurs, septal perforation, enlargement of the turbinates, and

nasal/sinus polyps can lead to pooling of or overproduction of secretions,

blockage of the normal pathways leading to chronic sinusitis, and chronic

irritation. The surgery is performed by an ear-nose-throat doctor

(otolaryngologist).



Humans can't live without blood. Without blood, the body's organs couldn't get theoxygen and nutrients they need to survive, we couldn't keep warm or cool off, fight

infections, or get rid of our own waste products. Without enough blood, we'd

weaken and die.

Here are the basics about the mysterious, life-sustaining fluid called blood.

Blood Basics

Two types of blood vessels carry blood throughout our bodies:

1. Arteries carry oxygenated blood (blood that has received oxygen from the

lungs) from the heart to the rest of the body.

2. Blood then travels through veins back to the heart and lungs, where it receives

more oxygen.

As the heart beats, you can feel blood traveling through the body at pulse points —

like the neck and the wrist — where large, blood-filled arteries run close to the

surface of the skin.

The blood that flows through this network of veins and arteries is whole blood,

which contains three types of blood cells:

1. red blood cells (RBCs)

2. white blood cells (WBCs)

3. platelets

In babies and young kids, blood cells are made within the bone marrow (the soft

tissue inside of bones) of many bones throughout the body. But, as kids get older,blood cells are made mostly in the bone marrow of the vertebrae (the bones of the

spine), ribs, pelvis, skull, sternum (the breastbone), and parts of the humerus (the

upper arm bone) and femur (the thigh bone).



The cells travel through the circulatory system suspended in a yellowish fluid called

plasma, which is 90% water and contains nutrients, proteins, hormones, and waste

products. Whole blood is a mixture of blood cells and plasma.

Red Blood Cells

Red blood cells (also called erythrocytes) are shaped like slightly indented, flattened

disks. RBCs contain the iron-rich protein hemoglobin. Blood gets its bright red color

when hemoglobin picks up oxygen in the lungs. As the blood travels through the

body, the hemoglobin releases oxygen to the tissues.

The body contains more RBCs than any other type of cell, and each has a life span

of about 4 months. Each day, the body produces new RBCs to replace those that

die or are lost from the body.

White Blood Cells

White blood cells (also called leukocytes) are a key part of the body's system for

defending itself against infection. They can move in and out of the bloodstream to

reach affected tissues. Blood contains far fewer WBCs than red blood cells, although

the body can increase WBC production to fight infection. There are several types of

WBCs, and their life spans vary from a few days to months. New cells are

constantly being formed in the bone marrow.

Several different parts of blood are involved in fighting infection. White blood cells

called granulocytes and lymphocytes travel along the walls of blood vessels. They

fight germs such as bacteria and viruses and may also attempt to destroy cells that

have become infected or have changed into cancer cells.

Certain types of WBCs produce antibodies, special proteins that recognize foreign

materials and help the body destroy or neutralize them. The white cell count (the

number of cells in a given amount of blood) in someone with an infection often is

higher than usual because more WBCs are being produced or are entering the

bloodstream to battle the infection.

After the body has been challenged by some infections, lymphocytes "remember"

how to make the specific antibodies that will quickly attack the same germ if it

enters the body again.



Platelets

Platelets (also called thrombocytes) are tiny oval-shaped cells made in the bone

marrow. They help in the clotting process. When a blood vessel breaks, platelets

gather in the area and help seal off the leak. Platelets survive only about 9 days in

the bloodstream and are constantly being replaced by new cells.

Important proteins called clotting factors are critical to the clotting process.

Although platelets alone can plug small blood vessel leaks and temporarily stop or

slow bleeding, the action of clotting factors is needed to produce a strong, stable

clot.

Platelets and clotting factors work together to form solid lumps to seal leaks,

wounds, cuts, and scratches and to prevent bleeding inside and on the surfaces of

our bodies. The process of clotting is like a puzzle with interlocking parts. When the

last part is in place, the clot happens — but if even one piece is missing, the final

pieces can't come together.

When large blood vessels are severed (or cut), the body may not be able to repair

itself through clotting alone. In these cases, dressings or stitches are used to help

control bleeding.

Nutrients in the Blood

Blood contains other important substances, such as nutrients from food that has

been processed by the digestive system. Blood also carries hormones released by

the endocrine glands and carries them to the body parts that need them.

Blood is essential for good health because the body depends on a steady supply of

fuel and oxygen to reach its billions of cells. Even the heart couldn't survive without

blood flowing through the vessels that bring nourishment to its muscular walls.

Blood also carries carbon dioxide and other waste materials to the lungs, kidneys,

and digestive system to be removed from the body.

Blood cells and some of the special proteins blood contains can be replaced or

supplemented by giving a person blood from someone else via a transfusion. In

addition to receiving whole-blood transfusions, people can also receive transfusions



of a particular component of blood, such as platelets, RBCs, or a clotting factor.

When someone donates blood, the whole blood can be separated into its different

parts to be used in this way.

Diseases of Red Blood Cells

Most of the time, blood functions without problems, but sometimes, blood disorders

or diseases can cause illness. Diseases of the blood that commonly affect kids can

involve any or all of the three types of blood cells. Other types of blood diseases

affect the proteins and chemicals in the plasma that are responsible for clotting.

The most common condition affecting RBCs is anemia, a lower-than-normal number

of red cells in the blood. Anemia is accompanied by a decrease in the amount of

hemoglobin. The symptoms of anemia — such as pale skin, weakness, a fast heart

rate, and poor growth in infants and children — happen because of the blood's

reduced capacity for carrying oxygen.

Anemia typically is caused by either inadequate RBC production or unusually rapid

RBC destruction. In severe cases of chronic anemia, or when a large amount of

blood is lost, someone may need a transfusion of RBCs or whole blood.

Anemia resulting from inadequate RBC production. Conditions that can cause

a reduced production of red blood cells include:

Iron deficiency anemia. The most common type of anemia, it affects kids and

teens of any age who have a diet low in iron or who've lost a lot of RBCs (and

the iron they contain) through bleeding. Premature babies, infants with poor

nutrition, menstruating teenage girls, and those with ongoing blood loss due to

illnesses such as inflammatory bowel disease are especially likely to have iron

deficiency anemia.

Lead poisoning. When lead enters the body, most of it goes into RBCs where it

can interfere with the production of hemoglobin. This can result in anemia. Lead

poisoning can also affect — and sometimes permanently damage — other body

tissues, including the brain and nervous system. Although lead poisoning is

much less common now, it still is a problem in many larger cities, especially

where young children might ingest paint chips or the dust that comes from lead-

containing paints peeling off the walls in older buildings.

Anemia due to chronic disease. Kids with chronic diseases (such as cancer or

human immunodeficiency virus infection) often develop anemia as a

complication of their illness.



Anemia due to kidney disease. The kidneys produce erythropoietin, a

hormone that stimulates production of red cells in the bone marrow. Kidney

disease can interfere with the production of this hormone.

Anemia resulting from unusually rapid red blood cell destruction. When

RBCs are destroyed more quickly than normal by disease (a process calledhemolysis), the bone marrow will make up for it by increasing production of new

red cells to take their place. But if RBCs are destroyed faster than they can be

replaced, a person will develop anemia.

Several causes of increased red blood cell destruction can affect kids:

G6PD deficiency. G6PD is an enzyme that helps to protect red blood cells from

the destructive effects of certain chemicals found in foods and medications.

When the enzyme is deficient, these chemicals can cause red cells to hemolyze,

or burst. G6PD deficiency is a common hereditary disease among people of

African, Mediterranean, and Southeast Asian descent.

Hereditary spherocytosis is an inherited condition in which RBCs are

misshapen (like tiny spheres, instead of disks) and especially fragile because of

a genetic problem with a protein in the structure of the red blood cell. This

fragility causes the cells to be easily destroyed.

Autoimmune hemolytic anemia. Sometimes — because of disease or for no

known reason — the body's immune system mistakenly attacks and destroys

RBCs.

Sickle cell anemia, most common in people of African descent, is a hereditary

disease that results in the production of abnormal hemoglobin. The RBCsbecome sickle shaped, they cannot carry oxygen adequately, and they are easily

destroyed. The sickle-shaped blood cells also tend to abnormally stick together,

causing obstruction of blood vessels. This blockage in the blood vessels can

seriously damage organs and cause bouts of severe pain.

Diseases of the White Blood Cells Neutropenia occurs when there aren't enough of a certain type of white blood

cell to protect the body against bacterial infections. People who take certain

chemotherapy drugs to treat cancer may develop neutropenia. Human immunodeficiency virus (HIV) is a virus that attacks certain types of

WBCs (lymphocytes) that work to fight infection. Infection with the virus can

result in AIDS (acquired immunodeficiency syndrome), leaving the body prone

to infections and certain other diseases. Newborns can become infected with the

virus from their infected mothers while in the uterus, during birth, or from

breastfeeding, although HIV infection of the fetus and newborn is usually



preventable with proper medical treatment of the mother during pregnancy and

delivery. Teens and adults can get HIV from sex with an infected person or from

sharing contaminated needles used for injecting drugs or tattoo ink.

Leukemias are cancers of the cells that produce WBCs. These cancers include

acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute

lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL). The most

common types of leukemia affecting kids are ALL and AML. In the past 25 years,

scientists have made great advances in treating several types of childhood

leukemia, most notably certain types of ALL.

Diseases of Platelets Thrombocytopenia, or a lower than normal number of platelets, is usually

diagnosed because a person has abnormal bruising or bleeding.

Thrombocytopenia can happen when someone takes certain drugs or develops

infections or leukemia or when the body uses up too many platelets. Idiopathic

thrombocytopenic purpura (ITP) is a condition in which the immune system

attacks and destroys platelets.

Diseases of the Clotting System

The body's clotting system depends on platelets as well as many clotting factors

and other blood components. If a hereditary defect affects any of these

components, a person can have a bleeding disorder. Common bleeding disorders

include:

Hemophilia, an inherited condition that almost exclusively affects boys,

involves a lack of particular clotting factors in the blood. People with severe

hemophilia are at risk for excessive bleeding and bruising after dental work,

surgery, and trauma. They may experience episodes of life-threatening internal

bleeding, even if they haven't been injured.

Von Willebrand disease, the most common hereditary bleeding disorder, also

involves a clotting-factor deficiency. It affects both males and females.

Other causes of clotting problems include chronic liver disease (clotting factors are

produced in the liver) and vitamin K deficiency (the vitamin is necessary for the

production of certain clotting factors).



On average, the human body contains five litres of blood, and your red blood cells are replaced

every 120 days. Blood diseases can range from anaemia, which is common, to rare disorders

that affect only a few. You can use this section to find out more.

What is a blood test?Blood tests are a very useful diagnostic tool. Blood is made up of several different kinds of cells

and other compounds, including various salts and certain proteins.

The liquid portion of the blood is called plasma. When blood clots outside the body, the blood

cells and some of the proteins become solid. The remaining liquid is called serum, which can be

used in chemical tests and in tests to find out how the immune system fights diseases.

Doctors can take blood samples and grow the infectious organisms that cause an illness to

see exactly what they are through a microscope.

How is a blood test carried out?Blood samples for testing can be taken either from a vein (which carries blood to the heart) or

from an artery (which takes blood away from the heart).If only a few drops of blood are needed (for monitoring blood sugar in diabetes, for example) it

is enough to make a small prick in the tip of the finger and then squeeze the blood out.

Most blood tests are taken from a vein, commonly from those around the elbow. First a cord

(tourniquet) is tied around the upper arm to make the vein prominent. It may be a bit tight, but

this makes it much easier to take the test.

The site of the injection is then cleaned with spirit and then a needle is put into the vein. The

needle will be attached either to a low pressure blood test bottle, or to a syringe where the

plunger is pulled back to create low pressure. When the necessary amount of blood has been

extracted, the needle is removed and a little ball of cotton wool is held over the wound. This

should be pressed for one to two minutes before applying a sticking plaster.If blood is taken from an artery, it is usually extracted from the wrist where there is an artery that

is very close to the skin. This may be slightly uncomfortable, as the artery wall has more pain

nerves in it than the vein wall.

After taking blood from an artery it may be necessary to hold a ball of cotton wool on the place

where the injection was made for about five minutes to stop any bleeding.

Some people are very sensitive to needles and the sight of their own blood and may

feel faint when a blood sample is taken. This is not uncommon and can be reduced by sitting or

http://www.netdoctor.co.uk/health_advice/examinations/microscopy.htm



http://www.netdoctor.co.uk/hearthealth/diabetes.htm



http://www.netdoctor.co.uk/diseases/facts/fainting.htm








lying down while the sample is taken. If you feel faint or think that you might feel faint,

immediately tell the person who is taking blood.

What do doctors examine in the blood?Blood contains two main elements: the fluid that is called plasma and cells. There are three

kinds of cells: red blood cells, white blood cells and platelets. To get the information they needfrom the blood, doctors actually do several tests with the blood sample. These include

measurements of the levels of the cells and a blood smear. A blood smear is a film of blood

placed on a slide to allow doctors to look at the individual cells under a microscope. These tests

are listed below.

Red blood cellsOne of the most important red blood cell tests is used to find out how much haemoglobin there

is in the blood. Haemoglobin carries oxygen around your body. This is called the haemoglobin

concentration or level.

Another important test, the mean corpuscular volume or MCV test, measures the size of the red

blood cells.If a person suffers from anaemia their haemoglobin level will always be less than normal. But

the size of the red blood cells depends on the type of anaemia you have.

A haematocrit test measures the total volume that red blood cells take up in the blood. In

practice, this is done by spinning a test tube of blood until the red blood cells - the heaviest part

of the blood - go to the bottom of the tube. Then their volume is calculated.

Almost all types of anaemia will cause a low haematocrit (a low red blood cell volume), as will

very severe bleeding. A high haematocrit can occur if a person is dehydrated from not drinking

enough fluid or because they are losing fluid as happens with diarrhoea, burns and sometimes

surgery.

If the red blood cells are pale, it can be a sign of iron deficiency anaemia. If they have astrange shape, it may be because of sickle cell anaemia orpernicious anaemia.

Doctors also add stains to the blood smear to test the blood for parasites, for example in the

case of sleeping sickness or malaria. They may also test for bacteria in the case of blood

poisoning.

White blood cells (WBC)The doctor counts the total number of white blood cells and works out how many different types

of white blood cells the patient has. This is called the differential WBC count.

The number of white blood cells may go up and this may be because of a bacterial infection,

bleeding or a burn. More rarely the cause of a raised white count is due to leukaemia, cancer

or malaria. A person may lose white blood cells because they have autoimmune problems - this is where

the antibodies that should fight diseases attack the body instead. Other reasons for loss of white

blood cells include viral infections. More rarely, this can be a side effect of certain kinds of

medication.

Doctors keep an eye on white blood cells to work out how a disease is changing. By monitoring

the blood count in this way they can alter the patient's treatment as necessary.

http://www.netdoctor.co.uk/diseases/facts/anaemiairon.htm



http://www.netdoctor.co.uk/diseases/facts/diarrhoea.htm



http://www.netdoctor.co.uk/diseases/facts/burns.htm






http://www.netdoctor.co.uk/diseases/facts/anaemiab12.htm



http://www.netdoctor.co.uk/travel/diseases/sleeping_sickness.htm



http://www.netdoctor.co.uk/travel/diseases/malaria_disease.htm



http://www.netdoctor.co.uk/hearthealth/blood/leukaemiaacute.htm

















PlateletsPlatelets are very small cells in the blood that clump together at sites of injury to blood vessels.

They form the basis of the blood clot that would form if you cut yourself.

Low numbers of platelets can make a person vulnerable to bleeding, sometimes even without

injury occurring. Causes of low platelet counts include autoimmune diseases where you

produce an antibody to your own platelets, chemotherapy, leukaemia, viral infections and some

medicines.

High numbers of platelets make a person more vulnerable to blood clots. High platelet counts

are found in conditions involving the bone marrow such asleukaemia and cancer.

What are blood coagulation examinations?More tests will be needed if a patient is found to be suffering from a blood coagulation disorder

so that either their blood doesn't clot properly, or if it clots too well.

When a vein is damaged, usually a little blood clot will form on the inside. This clot is made of

blood platelets and proteins from the blood plasma (called the coagulation factors).

A person will bleed more than normal if they have a low number of blood platelets, if there is alack of coagulation factors, or if they don't work.

If the bleeding disorder is caused by problems with the coagulation factors more tests will be

needed. Sometimes a coagulation disorder is passed on in the family, but it could also be due to

a liver problem, as the liver makes many of the blood clotting factors.

Coagulation tests will be performed regularly for people who are on blood thinning medicines

such as warfarin. Doctors will change the dose of these medicines depending on the test

results.

Blood disordersCommon conditions

Common conditions

Anaemia due to folic acid deficiencyWhat is anaemia?

For most people, brown

bread and vegetables

are the main source of

folic acid.







You get anaemia when you don't have enough red blood cells. This makes it difficult for your

blood to carry oxygen, causing unusual tiredness and other symptoms.

The number of red blood cells can drop if there is:

a reduction in the number of red blood cells produced

an increase in the loss of red blood cells.

Red blood cells and oxygenThrough its pumping action, the heart propels blood around the body through the arteries.

The red blood cells take up oxygen in the lungs and carry it to all the body's cells. Your cells use

this oxygen to fuel the combustion (burning) of sugar and fat which produces the body's energy.

During this process carbon dioxide is created as a waste product. It binds itself to the red blood

cells that have delivered the oxygen.

The red blood cells then transport the carbon dioxide back to the lungs. We exchange this

carbon dioxide for fresh oxygen by breathing.

This process is called oxidation.

Term watch Artery: takes blood from the heart to the body.

Vein: takes blood back to the heart.

Why does a lack of folic acid cause anaemia?Red blood cells are made in the bone marrow and circulate in the blood. They only have a life

expectancy of about four months.

The body needs iron, vitamin B12 and folic acid (one of the B group of vitamins) to produce

more red blood cells. If there is a lack of one or more of these nutrients, anaemia will develop.

A person who lacks folic acid may experience intestinal problems as well as the usual

symptoms of anaemia.

What are the causes of folic acid deficiency? Not eating enough foods that contain folic acid. Alcoholics and drug addicts are particularly at

risk, but so too are elderly people eating a poor diet. In rare cases, it is found

in teenagers who eat nothing but junk food.

In periods of rapid growth the body needs more folic acid – for example, in childhood and

during pregnancy. Folic acid also helps to protect the foetus against spina bifida (problems

with the spinal cord system not developing completely).

In some kinds of hereditary anaemia, such as haemolytic anaemia, the body breaks down red

cells very quickly. To compensate for this, the body produces more blood cells in response and

uses up all its stores of folic acid.

Certain medicines, such as anti-epileptic drugs and some antibiotics, can interfere with the

body's normal metabolism of folic acid. Pregnant women should always check with their doctor

before taking any kind of medication during pregnancy.

Chronic dialysis for kidney patients can remove folic acid from the blood.

Diseases of the small intestine, such as gluten intolerance (coeliac disease) and Crohn's

disease (inflammation of the intestine), can reduce its ability to absorb folic acid.




http://www.netdoctor.co.uk/health_advice/facts/vitamins_which.htm



http://www.netdoctor.co.uk/health_advice/facts/alcoholism.htm



http://www.netdoctor.co.uk/senior_health/index.shtml



http://www.netdoctor.co.uk/teenagehealth/index.shtml



http://www.netdoctor.co.uk/diseases/facts/anaemiapregnancy.htm



http://www.netdoctor.co.uk/medicines/effect/brain.shtml



http://www.netdoctor.co.uk/medicines/effect/infections.shtml



http://www.netdoctor.co.uk/diseases/facts/kidneyfailure.htm



http://www.netdoctor.co.uk/diseases/facts/glutenallergy.htm



http://www.netdoctor.co.uk/diseases/facts/crohnsdisease.htm


















What are the symptoms of this type of anaemia?If a person is otherwise healthy, it can take some time for the signs of anaemia to appear.

The first symptoms will be tiredness and palpitations (awareness of heartbeat).

Shortness of breath and dizziness (fainting) are also common.

If the anaemia is severe, it can result in angina (chest pain), headache and leg pains(intermittent claudication).

In addition to these general symptoms of anaemia, the following indicate folic acid deficiency:

red, irritated tongue that may appear shiny

reduced sense of taste

indigestion

changed bowel movements and often diarrhoea.

Bowel symptoms are more likely with a lack of folic acid rather than B12 deficiency.

In contrast to B12 deficiency, this type of anaemia doesn't lead to any symptoms in your

nervous system (muscle weakness, tingling in the hands and feet, nerve inflammation).

However, you can be deficient in B12 and folic acid at the same time.

How is anaemia due to a lack of folic acid

diagnosed?A blood sample is taken and sent off to the laboratory. An analysis of the red blood cells is

usually included with the result of the test.

In cases of folic acid deficiency, low levels of folic acid will be registered in the blood. The red

blood cells will be the usual colour, but larger than normal.

How is it treated?Folic acid supplements can reverse this type of anaemia, but your doctor will also look at

treating any underlying cause.The tablets are taken once a day and have few side-effects. They should be taken for at least

four months.

Folic acid tablets are only continued long term if the underlying cause cannot be corrected.

What can be done to avoid folic acid deficiency? Eat a varied diet.

Good sources of folic acid include beans, oatmeal, mushrooms, broccoli, asparagus, beef and

liver.

Consult your GP if you experience any of the above symptoms.

Women should take a folic acid supplement during pregnancy and ideally before conception.

This is because a baby's spinal cord develops very early on in pregnancy. The recommendeddose is 400 micrograms daily, and more if you have had a previous pregnancy complicated by

spina bifida. Your doctor or pharmacist will be able to advise.

Other people also read:Vitamins and minerals – what do they do?: we show you the recommended daily amounts

(RDAs).

Anaemia due to iron deficiency: how is it treated?




http://www.netdoctor.co.uk/diseases/facts/angina.htm



http://www.netdoctor.co.uk/diseases/facts/headache.htm






http://www.netdoctor.co.uk/hearthealth/blood/anaemiab12.htm



http://www.netdoctor.co.uk/health_advice/examinations/bloodsamples.htm



http://www.netdoctor.co.uk/diet-and-nutrition/medicines/folic-acid-5mg-tablets.html


http://www.netdoctor.co.uk/dietandnutrition/index.shtml



http://www.netdoctor.co.uk/diet-and-nutrition/medicines/folic-acid-400-microgram-tablets.html






















Anaemia during pregnancy: find out what can be done to avoid anaemia during pregnancy.

Folic acid supplement: How does it work?

Anaemia due to iron deficiency

What is anaemia?

Good sources of iron

include liver, beef,

wholemeal bread,cereals, eggs and dried

fruit.






Red blood cells and oxygen



Through its pumping action, the heart propels blood around the body through the arteries.







This process is called oxidation.Why does a lack of iron cause anaemia?Red blood cells are made in the bone marrow and circulate in the blood. They only have a life


The body needs iron, vitamin B12 and folic acid (one of the B group of vitamins) to produce









http://www.netdoctor.co.uk/diseases/facts/anaemiafolicacid.htm









Iron deficiency anaemia is the most common type of anaemia. In the UK 8 per cent of women

have this type of anaemia.

Iron deficiency is more frequent in women who smoke, eat a diet low in iron and have heavy

periods. It is also common in vegetarians.

What causes this type of anaemia?Most childhood cases are caused by a poor diet that contains little iron.

In adults the most common cause is losing blood faster than the body can replace it.

A lack of iron in the diet is common in vegans and vegetarians because the main dietary

source is red meat.

Babies can develop iron deficiency, especially if they are premature. Storing iron is not usually

completed until the final stages of pregnancy.

The body needs more iron when a large amount of cell divisions occur, such asin

pregnancy and during periods of rapid childhood growth.

Loss of blood through heavy menstruation can deplete iron stores.

Diseases of the small intestine such as gluten intolerance (coeliac disease) and Crohn's

disease (inflammation of the intestine) can reduce its ability to absorb iron.

If there seems to be no cause for the iron deficiency, consult your doctor. Less commonly,

small ruptures in the intestine due to cancer or polyps (small growths), and ulcers in the

stomach and small intestine can cause iron deficiency anaemia. The loss of blood from the

digestive tract may be so slight as to be undetected on its own.

What are the symptoms of iron-deficiency anaemia?If a person is otherwise healthy, it can take some time for the signs of anaemia to appear.



If the anaemia is severe, you may experience angina (chest pain), headache or leg pains(intermittent claudication).

Besides these general symptoms of anaemia, in pronounced and long-term cases of iron

deficiency there may be:

burning sensation in the tongue

dryness in the mouth and throat

sores at the corners of the mouth

altered sense of touch

brittle, spoon-shaped nails with vertical stripes and a tendency to fray

pica (an insatiable craving for a specific food, eg liquorice)

brittle hair

difficulty swallowing.

In rare cases, iron deficiency can cause permanent changes to the soft lining in the throat

(Plummer-Vinson syndrome). This condition is a preliminary stage to cancer of the

oesophagus.

http://www.netdoctor.co.uk/health_advice/facts/smokehealth.htm



http://www.netdoctor.co.uk/health_advice/facts/menstruationheavy.htm




http://www.netdoctor.co.uk/diet-and-nutrition/turning-vegetarian.htm














http://www.netdoctor.co.uk/diseases/facts/bowelcancer.htm



http://www.netdoctor.co.uk/diseases/facts/colonpolyps.htm












http://www.netdoctor.co.uk/diseases/facts/oesophaguscancer.htm






















How is anaemia diagnosed?A blood sample is taken and sent off to the laboratory. An analysis of the red blood cells is


In pronounced iron deficiency the red blood cells will be small and pale. Otherwise, further

analysis is needed to examine the proteins called ferritin and transferrin that are involved in thestorage and transport of iron through the body.

How is it treated?Iron tablets will rapidly reverse anaemia, so long as any underlying cause of blood loss has

been treated. The tablets can irritate the stomach and should be taken after food to prevent this.

Iron tablets may colour the stools black and cause constipation or diarrhoea.

There may be a need for intramuscular iron injections to be given instead of tablets, but this is

far less common.

What can be done to avoid anaemia? Eat a varied, well-balanced diet that contains foods from all the food groups

(protein, carbohydrate, fat, fruit, vegetables).

Good sources of iron include liver, beef, wholemeal bread, cereals, eggs and dried fruit.

If you often get heavy periods, it's a good idea to seek medical advice because you may be at

risk of anaemia.

If you are pregnant or planning to become pregnant, talk to your doctor about iron

supplements.

What is anaemia?

Fish is a good source of

vitamin B12.






Red blood cells and oxygenThrough its pumping action, the heart propels blood around the body through the arteries.






http://www.netdoctor.co.uk/medicines/treatments-for-blood-disorders.shtml


http://www.netdoctor.co.uk/diseases/facts/constipation.htm






http://www.netdoctor.co.uk/focus/nutrition/facts/detoxification/dietaryprotein.htm



http://www.netdoctor.co.uk/focus/nutrition/facts/lifestylemanagement/carbohydrates.htm



http://www.netdoctor.co.uk/focus/nutrition/facts/lifestylemanagement/fats.htm



http://www.netdoctor.co.uk/health_advice/fiveportionsfruitveg.htm





















This process is called oxidation.



Why does vitamin B12 deficiency cause anaemia?Red blood cells are made in the bone marrow and circulate in the blood. They only have a life


The body needs iron, vitamin B12 and folic acid(one of the B group of vitamins) to produce


Anaemia due to a lack of vitamin B12 is also called pernicious anaemia.

Vitamin B12 is essential for the nervous system, which is why a deficiency can also causeinflammation of the nerves (neuritis) and dementia (mental deterioration).

Elderly people are particularly at risk of vitamin B12 deficiency, although it may also be present

in the young women.

What causes this type of anaemia? Not eating enough foods that contain vitamin B12. A vegetarian or vegan diet can cause

deficiency because vitamin B12 is only found in foods of animal origin, such as meat, fish,

eggs and milk.

Inability of the small intestine to absorb vitamin B12. The stomach produces a substance called

intrinsic factor to absorb vitamin B12 from food. In the UK, the most common cause of B12

deficiency is a lack of intrinsic factor.

What causes a low production of intrinsic factor? Antibodies can form against the cells that produce intrinsic factor. The cells then die, leading to

B12 deficiency and anaemia.

Stomach cancer and ulcers can take up so much room in the stomach that there are too few

cells left to produce intrinsic factor.

Diseases of the small intestine, fish tapeworm and the after-effects of bowel surgery can all

result in the surface of the small intestine being too small to absorb B12 and intrinsic factor

effectively.

What are the symptoms of this type of anaemia?If a person is otherwise healthy, it can take some time for the signs of anaemia to appear.



If the anaemia is severe, it can result in angina (chest pain), headache and leg pains

(intermittent claudication).

Red, sore tongue and mouth.

Weight loss.







http://www.netdoctor.co.uk/diseases/facts/dementia.htm





http://www.netdoctor.co.uk/healthy-living/recipes/main-courses/vegetarian/index.shtml



http://www.netdoctor.co.uk/diseases/facts/stomachcancer.htm


http://www.netdoctor.co.uk/diseases/facts/pepticulcer.htm
























Diarrhoea.

Some people with vitamin B12 deficiency will experience symptoms in their nervous system

first, such as:

altered or reduced sense of touch

less sensitivity to vibration (inability to feel the vibrations of a tuning fork)

colour blindness tingling in the hands and feet

muscle weakness

difficulties with walking and coordination

psychological symptoms, such as memory loss, confusion and depression.

With pernicious anaemia there is an increased danger of developing stomach cancer.

How is pernicious anaemia diagnosed?A blood sample is taken and sent off to the laboratory. An analysis of the red blood cells is


In cases of vitamin B12 deficiency, the red blood cells will be the usual colour but larger than

normal.

If the blood test shows a low vitamin B12 count, it must be established whether it is pernicious

anaemia or if there is some other cause.

The Schilling test measures the body's ability to absorb vitamin B12 from the bowel. This will

show whether the anaemia is caused by a lack of intrinsic factor.

Blood tests will also confirm if you have any antibodies to intrinsic factor.

People with a history of diabetes, thyroid upset or vitiligo (depigmentation of the skin), whether

in themselves or in there family, are at higher risk of developing intrinsic factor antibodies and

pernicious anaemia.

How is pernicious anaemia treated?Your GP will prescribe vitamin B12 injections. These are given every three months and will

usually be continued throughout life. The injections have few side-effects.

Even if the pernicious anaemia is treated, there is a slightly increased risk of stomach cancer.

While the injections can cure vitamin B12 deficiency, if the treatment is started too late there is a

risk of permanent damage to the nervous system.

What can be done to avoid vitamin B12 deficiency? Eat a varied diet. Good sources of vitamin B12 are liver, fish and eggs.

Vegans should take vitamin B12 supplements to avoid deficiency.

If a family member has pernicious anaemia, you should take extra care to prevent deficiency.

Anyone who has undergone surgery in their small intestine or stomach should pay attention toany of the symptoms mentioned above.

Nosebleeds (epistaxis)Reviewed by Dr Robert Mills, consultant otolaryngologist

16



http://www.netdoctor.co.uk/diseases/facts/depression.htm









http://www.netdoctor.co.uk/diseases/facts/diabetes.htm



http://www.netdoctor.co.uk/diseases/facts/vitiligo.htm



http://www.netdoctor.co.uk/diet-and-nutrition/medicines/hydroxocobalamin.html



http://www.netdoctor.co.uk/whoisnd.htm



http://www.netdoctor.co.uk/diseases/facts/nosebleeds.htm














Where does the blood in a nosebleed come from?The blood usually comes from a blood vessel located in the front of the nasal septum (nasal

partition) or further back in the nasal cavity.

What can cause a nosebleed?

A nosebleed usually

occurs due to a ruptured

blood vessel located in the

front of the nasal septum.

Picking the nose.

A blow to the nose or damage to the mucous membrane.

A cold or flu.

A nasal allergy.

Dry mucous membranes in the nose due to a stuffy indoor atmosphere.

Hypertension (high blood pressure) - rarely.

Certain kinds of medication; for instance, products that reduce the viscosity of the blood (such

as aspirin (eg Micropyrin)and non-steroidal anti-inflammatory drugs).

Exposure to chemicals that may irritate the mucous membranes.

Deviation of the nasal (septum).Most nosebleeds occur for no obvious reason.

Other rare causes of nosebleeds Blood diseases such as leukaemia or haemophilia.

Tumours in the nasal cavity.

Osler's disease.

Danger signals in a severe nosebleed Heavy bleeding.

Palpitation, shortness of breath and turning pale.

Swallowing large amounts of blood, which will cause you to vomit.

How to avoid nosebleeds Avoid damaging the nose and excessive nose-picking.

Seek medical treatment for any disease causing the nosebleeds.

Get a humidifier if you live in a dry climate or at high altitude.

What to do if you get a nosebleed Sit in an upright position with your head bent forward.


















http://www.netdoctor.co.uk/diseases/facts/colds.htm



http://www.netdoctor.co.uk/diseases/facts/influenza.htm



http://www.netdoctor.co.uk/diseases/facts/hayfever.htm



http://www.netdoctor.co.uk/diseases/facts/hypertension.htm


http://www.netdoctor.co.uk/heart-and-blood/medicines/micropirin.html


http://www.netdoctor.co.uk/medicines/effect/joints.shtml






http://www.netdoctor.co.uk/diseases/facts/oslersdisease.htm












Hold the tip of your nose for five minutes while breathing through the mouth.

If the bleeding stops and then returns, hold your nose for 8 to 10 minutes. This will allow time

for the blood to clot.

Applying an ice-pack to your nose may help.

Good advice Do not blow your nose for the next 12 hours after the bleeding has stopped. This will help the

dried blood to remain in place.

Do not swallow the blood. It can cause you to become nauseous and vomit, or could conceal a

greater blood loss.

If you frequently suffer from nosebleeds you should seek help from your doctor.

The most likely development The bleeding usually stops if you follow the above instructions.

Heavy bleeding may require hospital treatment and, in rare cases, a blood transfusion.

How is heavy bleeding treated and what kind of

medication can be given?Contact your doctor if the advice described above does not help stop the bleeding.

Initially, the doctor will try to stop the bleeding by using something that will make the blood

vessels contract.

When the bleeding has stopped, the doctor may choose to cauterise the source of the bleeding

with a chemical to prevent it bleeding again.

If the bleeding fails to stop, it may be necessary to put a pack in the nose.

In rare cases, an operation may be necessary to tie off the blood vessel that supplies the

bleeding area.

If the bleeding is caused by another disease, such as increased blood pressure, it is veryimportant to seek treatment to avoid recurrence of nosebleeds.

Nosebleeds can be very intermittent, and between bleeds it may be very difficult to determine

their source. If this occurs it is best to ensure that the nose is inspected during a bleed, which

might mean needing to be assessed 'out of hours' by the on-call GP or local casualty unit.

Acute leukaemiaReviewed by Dr Rachel Green, consultant haematologist

32 What is leukaemia?Leukaemia, or blood cancer, is a disease of unknown cause where the bone marrow produces

large numbers of abnormal cells. This means that the normal marrow is pushed into smaller and

smaller areas, which results in fewer cells being produced and leads to some of the symptoms

listed below.











There are many types of leukaemia and each of them is classified according to the exact cell

type affected by the disease.

Chronic leukaemia is a slowly progressive form of leukaemia and tends to involve more mature

cell types.

Acute leukaemia is rapidly progressive if not treated and involves more immature cells. It

develops rapidly from the earliest forms of cells in the immature bone marrow cells (blasts). Itrequires urgent medical treatment but is generally responsive to chemotherapy.

Acute leukaemia is a rare disease that is more common in children and young people. However,

their survival rate is better than in older people.

What are the symptoms of acute leukaemia? Sudden appearance of symptoms.

An unnaturally pale complexion (anaemia).

Fatigue.

Pain in the joints. When children are affected, this is sometimes mistaken for growing pains.

Repeated infections, such as sore throats.

Acute leukaemia is also usually accompanied by nosebleeds and bruising easily, often without

any kind of blow or fall.

If any of the above symptoms develop, it is advisable to consult a doctor. Parents are

understandably afraid of leukaemia, but fortunately, the diagnosis often turns out to be

something else entirely, as many other diseases have similar symptoms.

How is acute leukaemia diagnosed?Many forms of leukaemia can be diagnosed by blood tests. Commonly, the acute leukaemia

cell (blasts) can be seen circulating in the blood.

A bone marrow test will also be performed to diagnose the type of cells involved, as this can

help doctors decide on the best choice of treatment.Acute leukaemia is usually easy to diagnose.

How is acute leukaemia treated?Most patients with acute leukaemia will be referred to specialist units for investigation and

treatment.

These days, medical treatments are extremely effective and an ever-increasing number

of children and young people recover completely.

Treatment is usually with chemotherapy given through the veins. In most cases, chemotherapy

is given in courses over four to six months. Each course lasts four to five days. Chemotherapy

kills all fast dividing cells and this includes normal body cells as well as cancer cells.

The normal bone marrow is sensitive to chemotherapy and the blood counts may drop, makingthe patient vulnerable to infection and bleeding. This generally means that the patient has to

remain in hospital for weeks following chemotherapy. However the blood counts will recover

over time. Blood transfusions are likely to be given during this vulnerable period.

Chemotherapy can lead to hair loss, nausea, vomiting and diarrhoea. Doctors will give medicine

to prevent or reduce the vomiting and diarrhoea. Hair loss is not permanent and hair re-grows

after three to four months.

http://www.netdoctor.co.uk/hearthealth/blood/leukaemiachronic.htm





http://www.netdoctor.co.uk/diseases/facts/sorethroat.htm









http://www.netdoctor.co.uk/health_advice/facts/childrenhospital.htm



http://www.netdoctor.co.uk/medicines/effect/cancer.shtml












Sometimes a bone marrow transplant will also be recommended by the doctor. This is a way of

giving larger doses of treatment. It is a very aggressive form of treatment and so is only

recommended for young, fit patients. The cells used for this sort of treatment may be the

patient's own, donated by a brother or sister or by an unrelated donor.

The medical treatment can be unpleasant. Recognising this, specialised hospital staff are

trained to give as much help and support to patients as possible.

Aplastic anaemiaWritten by Professor TJ Hamblin, consultant haematologist

6 What is it?'Aplasia' means the lack of development of a tissue, cell or other body part. Aplastic anaemia is

the condition in which the bone marrow fails to produce blood cells. Normally, the bone marrowproduces:

red blood cells (which carry oxygen in the blood)

various types of white blood cell (which are part of the immune system)

platelets (which are involved in blood clotting).

Each of these different types of blood cell originates from simpler cells, known as precursors or

stem cells, which develop into the more specialised forms.

There are numerous reasons for the bone marrow to fail to produce blood cells in adequate

numbers, but in aplastic anaemia there is a marked deficiency of all the precursor cells that

should mature into adult blood cells.

Is it common?No, aplastic anaemia is a rare disease with an incidence in industrialised countries of between 5

and 10 cases per million per year.

How do I get aplastic anaemia?In 65 per cent of people the cause of aplastic anaemia is unknown (the technical term is

'idiopathic').

Rarely, the disease is present at birth (congenital). The commonest congenital form is Fanconi's

syndrome, but fewer than 1000 cases have ever been described.

As well as aplastic anaemia, patients with Fanconi's syndrome have short stature, abnormal

skin pigmentation, abnormalities of the bones of their arms and thumbs, kidney problems and

an elfin-like appearance. A characteristic abnormality of the chromosomes (random breaks) is

seen.

Drugs and environmental toxinsThe commonest known cause of aplastic anaemia is exposure to drugs or environmental toxins.

Benzene was the first known toxin to cause bone marrow failure. Despite this it is still widely

used in industry in the manufacture of drugs, dyes, explosives and other chemicals. Exposure




http://www.netdoctor.co.uk/diseases/facts/aplasticanaemia.htm







should be limited to 1 part per million, but this is often exceeded, especially in developing

countries. Other related organic chemicals also cause aplastic anaemia, including:

toluene (in glues)

the insecticides DDT and lindane

the explosive TNT

the wood preservative PCP petroleum distillates.

Drugs that cause aplastic anaemia may also be related to benzene. The

antibiotic,chloramphenicol and the anti-inflammatory, phenylbutazone are two examples.

Neither is commonly used in Western countries, but because they are cheap to produce, they

are in widespread use in the developing world. Other medicines with a moderate risk of aplastic

anaemia include gold salts and penicillamine (Distamine), used to

treat arthritis, carbamazepine (eg Tegretol) and phenytoin (eg Epanutin), used to

treat epilepsy, and the diuretic acetazolamide (eg Diamox).

A large number of drugs have been associated with occasional cases of aplastic anaemia. Most

of these are useful drugs and cannot easily be replaced. In Britain, doctors use a system calledthe 'yellow-card' scheme to report suspected side effects of drugs, such as aplastic anaemia.

Cytotoxic drugs are those that are designed to be directly toxic to cells in the treatment of

cancer. Some destroy bone marrow cells (for example, in the treatment of leukaemia). Normally

the marrow recovers after a short period. An overdose of these drugs causes severe, prolonged

aplasia.

Radiotherapy (treatment with X-rays) suppresses the bone marrow, and may be intentionally

used to do so in preparation for bone marrow transplantation. The use of these treatments

should be confined to specialised centres where careful monitoring of the blood count takes

place.

Some cases of aplastic anaemia have occurred after viral infections. In particular,hepatitisA, hepatitis B and 'non-A, non-B, non-C' hepatitis have been implicated, and more rarely the

Epstein-Barr virus.

Very rarely aplastic anaemia occurs during pregnancy. It is not clear whether this is just a

coincidence. Sometimes the disease recovers spontaneously at the end of pregnancy.

What is the disease process?Nowadays, treatment of aplastic anaemia is directed on the assumption that the disease is

related to the immune system.

The first evidence for this came from the early days of bone marrow transplantation. Sometimes

the marrow that regrew after the conditioning treatment was of the person's own type rather

than that of the donor. This implied that there had been an immune attack going on in theperson's bone marrow, which was relieved by the intense dampening down of his or her

immune system by the treatment.

Other evidence comes from immunodeficient individuals (ie those with impaired immunity either

through disease or caused by their treatment) who receive a blood transfusion. They sometimes

develop transfusion-related graft-versus-host disease (GvHD) – in other words a rejection

http://www.netdoctor.co.uk/infections/medicines/chloramphenicol-capsules.html



http://www.netdoctor.co.uk/seniors-health/medicines/ridaura.html



http://www.netdoctor.co.uk/seniors-health/medicines/distamine.html



http://www.netdoctor.co.uk/diseases/facts/arthritis.htm



http://www.netdoctor.co.uk/brain-and-nervous-system/medicines/tegretol.html



http://www.netdoctor.co.uk/brain-and-nervous-system/medicines/epanutin.html



http://www.netdoctor.co.uk/diseases/facts/epilepsy.htm



http://www.netdoctor.co.uk/seniors-health/medicines/diamox.html








http://www.netdoctor.co.uk/diseases/facts/hepatitisa.htm




http://www.netdoctor.co.uk/diseases/facts/hepatitisb.htm


















response. One of the forms that it can take is aplastic anaemia, demonstrating that an

immunological attack can cause aplastic anaemia.

What are the symptoms?The person complains of increasing tiredness, weakness and shortness of breath. Bleeding,

bruising and blood spots may be noticed.Sore throats and other infections are noticeable. A high temperature with shivering attacks is an

important symptom that demands immediate medical attention.

How is aplastic anaemia diagnosed?The following combination of three symptoms should raise suspicion of bone marrow failure:

anaemia - tiredness, weakness and breathlessness

low white cell count in the blood (neutropenia) - fever, sore throat, shivering attacks

low platelet count (thrombocytopenia) - bruising and bleeding.

On examination the doctor may find pale skin, possibly the signs of heart failure, bruises and

petechiae (small blood spots in the skin and mouth), mouth ulcers and fever. The doctor will

examine the back of the eye with an ophthalmoscope and is likely to see small haemorrhageson the retina.

An important negative finding is the absence of enlarged lymph nodes or an enlarged spleen.

Their presence would point to other diagnoses, such as lymphoma or leukaemia.

The most important test is the full blood count, which will show reduced numbers of red cells,

white cells (neutropenia) and platelets (thrombocytopenia) - in other words all of the cellular

components of blood. This feature is called pancytopenia.

The level of the neutrophil count defines the severity of the disease. Neutrophils are normally

the most numerous of the various types of white cell we have in our blood and they are

particularly involved in combating infection by bacteria and fungi.

Counts below 0.5 x 109/L mean severe aplastic anaemia. Counts below 0.2 x 109/L mean very severe aplastic anaemia.

What can your doctor do?Whenever pancytopenia is suspected on the basis of the symptoms described above, your

doctor should request a full blood count.

If the blood count shows reduced numbers of red cells, white cells and platelets he should

request an urgent referral to a haematologist. The haematologist should see you within 48

hours.

What else could it be?The most important distinction that the haematologist must make is between aplastic anaemia

and acute leukaemia, which can show very similar blood pictures. For this reason a bone

marrow sample is essential. The doctor will take samples both of the fluid of the bone marrow

(an aspirate) and of the more solid bone marrow structure (a trephine biopsy). For most cases

the diagnosis is easily made.

In acute leukaemia the marrow is full of abnormal cells but in aplastic anaemia it is empty and

comprises mainly fat spaces.




http://www.netdoctor.co.uk/diseases/facts/thrombocytopenia.htm















Other possible diagnoses will also be sorted out by the bone marrow. Myelodysplastic

syndrome is one in which there is faulty blood cell production by abnormal bone marrow cells

rather than by the lack of precursor cells. It also causes pancytopenia but the bone marrow is

full of cells that are recognisably abnormal.

Some cases of megaloblastic anaemia (including pernicious anaemia) also have

pancytopenia, but again the bone marrow is characteristically full of cells. The doctor will alsomeasure blood levels of vitamin B12 and folic acid to exclude this possibility.

Any condition that infiltrates the bone marrow can also cause pancytopenia, but these should be

diagnosable by the bone marrow investigation. Likely conditions include lymphoma, myeloma

and secondary cancer.

Occasionally some of these conditions may present with empty bone marrows just like aplastic

anaemia. Experts can sometimes distinguish small numbers of leukaemic cells or

myelodysplastic cells and are therefore able to make the diagnosis of hypoplastic

(underdeveloped) acute leukaemia or hypoplastic myelodysplastic syndrome. Sometimes these

conditions supervene after treatment of the aplastic anaemia, and the assumption is that they

have been there all along.An important supplementary diagnosis is paroxysmal nocturnal haemoglobinuria (PNH). In this

condition the red cells lack a special molecule on their surface that is used to anchor many other

types of protein to the membrane of the red cell - known as the phosphatidylinositol glycan

(GPI) anchor. As a consequence, the red cells are very susceptible to destruction (haemolysis).

It has been known for a long time that the two conditions can occur together. PNH has been

described as occurring in between 15 and 52 per cent of people with aplastic anaemia at

diagnosis. The diagnosis of PNH is important because it can lead to problems with thrombosis

(blood clots) and difficulties with blood transfusion.

What can you do yourself?It is important that you take charge of your illness:

try to find out all you can about aplastic anaemia and the various treatment options.

don't be afraid to ask questions of your doctor and other patients.

you could encourage your friends and family to become blood and bone marrow donors.

join a support group and read about ways to cope.

check with your doctor about what things to avoid like salads and soft cheeses, which carry

some infection risk.

your doctor will also give you advice about how to recognise the first signs of infection.

you should take your temperature regularly.

it is dangerous to live too far from a hospital capable of giving the right sort of supportive care.

before trying complementary therapies, always consult your doctor.

What can your doctor do?The first thing your doctor will do is ask about the various drugs and toxins that could have

caused the disease, and make sure that they are avoided in future.

He will then take blood samples to tissue type you and your close relatives in case a bone

marrow transplant is needed. Severe and very severe aplastic anaemia are life-threatening

conditions that need to be taken very seriously. Leaving the disease untreated is not an option.







Supportive carePatients with mild aplastic anaemia will only require supportive care and often very little of that.

Sometimes all that is needed is to remove the noxious agent and wait to see if spontaneous

recovery will occur.

Even if you are going to receive a bone marrow transplant or immunosuppressive therapy youwill need short-term treatment to protect you from the consequences of pancytopenia.

Infections are the major hazard. This is especially so if you need an indwelling (Hickman-like)

intravenous line. These are catheters that are inserted in to the main veins within the chest and

can be left in place for a long time in order to give chemotherapy drugs repeatedly. In general

prophylactic or 'just in case' antibiotics are not favoured and your best protection is vigilance. A

fever of 38oC lasting more than two hours requires antibiotics in hospital. Your doctors may

change the antibiotics depending on the results of the bacterial investigations or response to

treatment.

Platelet transfusions are given to lessen the risk of bleeding. It is now usual practice to restrict

these to patients who are actually bleeding or those whose platelet count falls to below 10 x

109/L. Platelet transfusions should be screened to ensure they are free of contamination with

cytomegalovirus (CMV) as this virus can interfere with immunity. They should also be depleted

of white blood cells and, if being used after bone marrow transplantation or immunosuppression

they should also be exposed to X-ray sterilisation.

Red cell transfusions should also carry the same provisos, and are given for anaemia severe

enough to be causing symptoms. Patient who require long-term red cell support from repeated

transfusions are at risk from building up excess iron within the body and may require iron-

removing treatment (chelation therapy) withdesferrioxamine (Desferal).

Bone marrow transplantation from a sibling

For patients aged 50 or less with severe or very severe aplastic anaemia who have an HL-Acompatible sibling (ie a 'close match' in tissue type), bone marrow transplantation is the

treatment of choice.

This means that stem cells will be harvested from your brother or sister. This can either be done

in the operating theatre under a general anaesthetic or, increasingly these days, in the day-ward

using a cell separator.

Under general anaesthetic, bone marrow is sucked out of the hipbones on either side through a

hollow needle. About 4 per cent of the marrow is extracted in this way.

Using the cell separator, the donor's arm veins are connected via plastic tubes to a large

machine that works something like a spin dryer. The process separates the stem cells (which

are retained) from the rest of the blood (which is returned to the donor). About 10 litres of blood

are processed on each occasion. In either case the stem cells are transfused into the recipient

just like a bag of blood. Before this happens the patient must receive conditioning treatment to

allow the donor cells to 'take'.

For aplastic anaemia 'non-ablative' conditioning is used. This comprises large doses

of cyclophosphamide (eg Endoxana) and avoids radiotherapy. This preserves fertility, and

reduces the risk of lung disease and secondary malignancy, but increases the risk of rejection.

Graft rejection is prevented by ciclosporin (Neoral) therapy.




http://www.netdoctor.co.uk/heart-and-blood/medicines/desferal.html


http://www.netdoctor.co.uk/cancer/medicines/cyclophosphamide.html



http://www.netdoctor.co.uk/skin-and-hair/medicines/neoral.html









Immunosuppressive therapyIn patients over the age of 50 and those without an HL-A compatible sibling,

immunosuppression is the treatment of choice. The best regimen is a combination of anti-

thymocyte globulin (ATG) and ciclosporin. ATG is an antibody which acts against T-lymphocyes

- another type of white cell which is probably involved in the immune attack of the bone marrow.There are data to suggest that patients failing to respond to ATG have a 43 per cent chance of

responding to a second course.

Patients treated by immunosuppression have a much higher risk than those treated by bone

marrow transplantation of developing another disorder of the bone marrow, such as PNH, acute

leukaemia or myelodysplastic syndrome (these are known as 'clonal' marrow disorders). Factors

that increase the risk of these complications are:

age at diagnosis

multiple courses of immunosuppression

previous removal of the spleen

the addition of androgens (male sex hormones, which have been used in some previous

treatment regimes).

Bone marrow transplantation and

immunosuppression comparedThe survival rate for 168 patients transplanted at Seattle between 1978 and 1991 was 69 per

cent at 15 years. The 15-year survival rate for 227 patients treated by immunosuppression was

only 38 per cent. The difference in mortality is attributable to the development of clonal marrow

disorders, but the group treated by immunosuppression was older. Recent papers have

suggested that the outcome for bone marrow transplantation is still improving with 90 per cent

success rates for children and young adults.

Treatment failuresBone marrow transplant from a matched volunteer donor or a partially matched family donor

carries a greater risk of graft failure or severe graft-versus-host disease. The risk is most

acceptable in patients aged less than 20 and should be offered to such patients who fail the first

round of immunosuppressive therapy and to patients under 40 who fail a second round. For

older patients, further courses of ATG are an option, together with androgens, cytokines (small

proteins released by cells which influence the behaviour of other cells) and experimental

therapies.

Living with aplastic anaemia

Patients will need to steel themselves, at least initially, to a life dependent on the localhaematology service. While it is possible to continue working or schooling, there are certain

restrictions. Bodily contact sports must be avoided and a close watch must be kept for infection.

Transfusions will be a regular interruption. Some infections proceed very rapidly and need

instant remedies, hence the need for close contact with the haematology service.

All of the therapies carry side effects. ATG may cause a fever and often leads to 'serum

sickness'. During this phase there may be rashes and joint pains.



Ciclosporin can also cause problems with unusual hair growth and gum swelling. In higher

doses it can cause high blood pressure and kidney failure.

For these reason blood levels have to be regularly monitored. The major complication of bone

marrow transplantation is graft-versus-host disease. This shows itself as a rash, diarrhoea or

liver abnormalities.

Support for patientsThe Aplastic Anaemia Support Group, 16 Sidney Road, Borstal, Rochester ME1 3HF. Tel: 0870

487 0099. Email: [email protected] .

The Leukaemia Research Fund (LRF) publishes a useful booklet and supports research into

aplastic anaemia. Leukaemia Research Fund, 43 Great Ormond Street, London WC1N 3JJ. Tel:

020 7405 0101. Fax: 020 7242 1488. Email: [email protected].

Polycythaemia veraWritten by Dr Claire Harrison, Consultant Haematologist, St Thomas' Hospital,

London and Professor Samuel J Machin, Department of Haematology, University College

London Hospital

16 Polycythaemia vera (PV) is a rare medical condition that causes a high red cell count.

Red cells make up the majority of blood cells. They transport oxygen through the body, so their

main content is the oxygen-carrying protein, haemoglobin.

Term watch Essential thrombocythaemia (ET): a high platelet count, causing the blood to become sticky.

Myelofibrosis (MF): fibrous tissues scar and stiffen the bone marrow leading to reduced cellproduction and an enlarged spleen.

PV is one of a group of diseases called myeloproliferative diseases (MPDs) where the cells that

produce blood cells develop abnormally. Rarely, a high red cell count can also occur in the other

MPDs - essential thrombocythaemia (ET) and myelofibrosis (MF).

The main problem caused by polycythaemia vera is that the high number of red cells increases

the blood's 'thickness' (viscosity). Blood flow to organs is reduced and, rarely, blood clots can

form.

Who's at risk of polycythaemia vera?PV is predominantly a disease of the middle-aged and elderly population. It is very rare in

children. PV affects about one to two new patients per 100,000 of the population per year.

Symptoms of PVPV can cause many different problems, and you may experience none, some, or all of the

following.

Hyperviscosity (increased blood thickness), which can cause a red complexion (plethora),

headaches, visual disturbance, tiredness, breathlessness and bleeding.

Gout (in 10 to 15 per cent of patients).







http://www.netdoctor.co.uk/diseases/facts/polycythaemiavera.htm


http://www.netdoctor.co.uk/diseases/facts/thrombocytosis.htm



http://www.netdoctor.co.uk/diseases/facts/gout.htm










Itching.

Weight loss.

Fatigue.

Sweating.

Bleeding (haemorrhage).

Clotting (thrombosis).It has been suggested that PV increases the likelihood of stomach ulcers and high blood

pressure, but this is no longer thought to be the case.

Rarely, some people with PV can go on to develop myelofibrosis or acute myeloid leukaemia.

What causes polycythaemia vera?The cause of PV was a mystery until recently. In 2005 scientists around the world discovered

that many patients with bone marrow diseases (MPDs) had a mutation in a molecule

called JAK2.

JAK2 is a protein that functions as a signal to regulate cell functions. It sends messages in the

cell, telling it to grow and make more cells, or else to stop when the body does not need more

cells.

Researchers believe that in MPD patients, the mutation in JAK2 enhances messages asking for

more cell production. The result is too many blood cells which clog the blood and make it sticky.

The JAK2 mutation (also called the V617F JAK2) is found in about:

half of patients with too many platelets in their blood (ET)

half of patients with too many fibroblasts in their blood (MF)

95 per cent of patients with too many red cells in their blood (PV).

The test for the JAK2 mutation is very simple and can be done on a teaspoon of blood; results

generally take 1-2 weeks.

It's thought the JAK2 mutation is likely to occur as a result of some damage to the bone marrow,

for example as a result of viral infections or background radiation.

How is polycythaemia vera diagnosed?The initial process is the same as for other causes of a high red cell count (erythrocytosis).

A blood test will show any increase in red cells numbers. The blood test should then be

repeated to confirm the abnormal result. You will then be asked about your medical history and

have a physical examination.

A red cell mass study is usually then needed to see if you have an absolute erythrocytosis

(raised red cell mass, normal plasma volume). The study is often carried out in a hospital's

nuclear medicine department and involves mixing weak dyes with a sample of your blood and

then returning it to your body. The dyed cells distribute themselves among your red cells,

making it possible to calculate what the total mass of red cells must be.

Other diagnostic tests that may be performed include blood tests for kidney function, liver

function and levels of iron, folic acid, vitamin B12 and oxygen in the blood, urine test, chest X-

ray and ultrasound of the abdomen.

The diagnosis of PV is made by combining the investigations for erythrocytosis along with other

tests - for example, genetic testing for mutations in JAK2 or observing specific patterns of red

cell growth under certain conditions.











http://www.netdoctor.co.uk/diseases/facts/polycythaemia.htm










Term watch Polycythaemia anderythrocytosis are the medical terms for having too many red blood cells.

If there is an actual increase in number of red blood cells, you have absolute erythrocytosis.

You have PV if you have an absolute erythrocytosis for which there is no alternative cause plus

one or more of the following:

an enlarged spleen

increase in neutrophil (type of white cell) and/or platelet count in the blood

a mutation in the JAK2 protein

an abnormality of the chromosomes found on testing the bone marrow (known as cytogenetic

testing).

If your high red cell count only fulfils some of the criteria for PV, and there is no other

explanation for it, you have what's called idiopathic (unknown cause) erythrocytosis. In this

case, your red cell count will need careful monitoring for the emergence of PV or an alternative

cause.

How is PV treated?The aim of treatment is to control complications from PV or to reduce the likelihood of their

occurrence. However, it is difficult to predict who will suffer complications and some of the

treatments can have serious side-effects.

PV is treated by reducing the volume of red cells in the blood. This may be achieved by

venesection (removing blood with a syringe), or by treatment with drugs to slow the production

of red cells.

The choice of which treatment to use depends on:

your age

tolerance of venesection

whether you also have a high platelet count if you've already experienced bleeding or clotting.

An example of a guide to treatment decisions used in our centre is shown below.



Treatment flow chart for PV

Drugs that reduce red cell countHydroxycarbamide: previously known as hydroxyurea, this drug works by interfering with the

cell's metabolism. It is a common treatment for PV and usually needs to be taken daily. Your

blood count will be monitored at least every two to three months. It has relatively few side-

effects including some darkening of skin pigment, mouth and leg ulcers and rarely stomach and

bowel disturbance.

Hydroxycarbamide can damage DNA and may affect fertility, so shouldn't be used by pregnant

women or those trying to conceive. There have been concerns that this medicine may increase

the risk of PV transforming intoacute leukaemia. Though yet to be proven, the chance of this

occurring is likely to be in less than 5 per cent of patients over a period of 10 to 15 years.

Melphalan, busulfan and 32P: these drugs belong to a group medicines called alkylating

agents and used to be the main treatment for PV. They reduce cell count by binding to DNA and

damaging it, preventing complete separation of the two DNA strands at cell division. This means

these medicines can permanently damage fertility and the bone marrow.They increase the risk of PV turning into a form of acute leukaemia, probably in about 5-10 per

cent of patients over 10 years. Busulfan and 32P are still used to treat PV when other drugs

don't work, cause unacceptable side-effects or if you can't take the hydroxycarbamide tablets for

any reason.

Interferon: this is a naturally occurring protein that inhibits the growth of bone marrow cells. It

has to be given by injection, usually three times a week. Interferon is used in some patients with

PV, particularly in young people who want to preserve their fertility. It can be given to pregnant

women.

Interferon has also been reported to control, or reverse, the development of myelofibrosis. It has

many side-effects, including flu-like symptoms, hair loss, depression, liver and thyroidabnormalities: a high proportion of patients who are prescribed this drug will not be able to

continue using it.

Term watch Platelets: small cell fragments that clump together to form blood clots.

Anagrelide: this drug lowers the platelet count, but has only a very modest and unpredictable

effect upon red cells. It appears to work by reducing the size of the platelet-producing cells

within the bone marrow (the megakaryocytes). Anagrelide can only be used to treat PV when

additional means to control the red cells, such as venesection, are used. It is not currently

licensed in the UK as a treatment for PV.

Other treatmentsMost people with PV, with the possible exception of those with increased bleeding risk or a very

high platelet count, will be advised to take aspirin or a similar drug. Aspirin does not lower the

red cell count but can provide some protection against clotting complications by reducing the

'stickiness' of platelets.

Side-effects include bleeding and ulcers in the stomach and small intestine. For this reason,

aspirin is only used with caution if you have a platelet count in excess of 1500 million per ml.

http://www.netdoctor.co.uk/heart-and-blood/medicines/hydrea.html




http://www.netdoctor.co.uk/cancer/medicines/myleran.html



http://www.netdoctor.co.uk/heart-and-blood/medicines/nu-seals-75mg.html













Sometimes drugs that work in a similar manner to aspirin are used instead. Examples

are dipyridamole and clopidogrel. Some patients are also treated with warfarin, especially if

you have recently had a blood clot in a vein or have had multiple clots.

Gout is controlled both by reducing the number of red cells and by using a drug such

as allopurinol to increase excretion of the uric acid crystals that cause the symptoms. An acute

attack of gout is treated with painkillers.The itching associated with PV can be a particularly difficult problem to control. Measures used

include:

avoiding known triggers

soothing creams (aqueous cream with menthol)

histamine antagonists such as ranitidine may help.

It is also important to treat all other risk factors for arterial disease such as smoking, high blood

pressure, diabetes and high cholesterol.

Pregnancy and PVMany of the drug treatments are toxic to sperm and foetus. If you want to start a family, talk to

your haematologist about whether it's possible to change medication.

Women with PV that is treated through venesection alone are likely to need fewer procedures

throughout pregnancy when the blood naturally dilutes.

Pregnancy itself is associated with an increased risk of clotting. For this reason many pregnant

women will also be given aspirin and some will receive the anticoagulant drug heparin to

minimise the risk of clotting.

Long-term outlookThe outlook for PV is influenced significantly by the occurrence of complications - most

particularly those caused by clotting because these are more common and are often the most

serious.The chance of thrombosis increases with a person's age and when there has been a previous

problem caused by clotting.

Those people with PV who do not go on to develop other related diseases probably have a

normal or only slightly reduced life expectancy.

If you go on to develop myelofibrosis or acute myeloid leukaemia, the outlook is not as good.

MyelofibrosisOver a long period of time 20-30 per cent of patients with PV may develop a 'spent phase' of

their disease known as myelofibrosis. How much treatment to reduce red cells influences the

development of this condition is unclear and controversial.

People with myelofibrosis have low blood counts, develop enlarged spleens and are said to beat increased risk of developing acute myeloid leukaemia. Treatment can include:

support of the blood count (sometimes by red cell transfusion)

drugs such as hydroxyurea or interferon

irradiation (X-ray) treatment to reduce spleen size

removal of the spleen (splenectomy)

bone marrow transplants for a matched donor.

http://www.netdoctor.co.uk/heart-and-blood/medicines/persantin.html



http://www.netdoctor.co.uk/heart-and-blood/medicines/plavix.html



http://www.netdoctor.co.uk/heart-and-blood/medicines/marevan.html





http://www.netdoctor.co.uk/aches-and-pains/medicines/zyloric.html



http://www.netdoctor.co.uk/medicines/effect/heart.shtml











Depending upon the severity of fibrosis and the effectiveness of treatment, survival is on

average about three years. A few PV patients with myelofibrosis have been treated

experimentally with bone marrow transplantation.

Acute myeloid leukaemiaAcute myeloid leukaemia is associated with a very poor outlook because this form of leukaemia

is often resistant to treatment.

Occasionally good results have been reported in the very few patients who have been treated

with a bone marrow transplant either using:

their own bone marrow (autologous transplant)

a related donor (allogeneic transplant)

a volunteer unrelated donor.

Because of the high risk of mortality, these transplant procedures are not used very often in

acute myeloid leukaemia that develops from PV.

Thrombocytopenia (reduced plateletcount)Written by Dr Claire Harrison, Consultant Haematologist, St Thomas' Hospital,

London and Professor Samuel Machin, Department of Haematology, University College

London Hospital

246 What is thrombocytopenia?Thrombocytopenia is the term for a reduced platelet (thrombocyte) count. It happens whenplatelets are lost from the circulation faster than they can be replaced from the bone marrow

where they are made.

Did you know? All blood cells are created within the bone marrow.

Thrombocytopenia can result from:

a failure of platelet production

an increased rate of removal from blood.

What are platelets?

Platelets are tiny cells that circulate in the blood and whose function is to take part in the clottingprocess.

Inside each platelet are many granules, containing compounds that enhance the ability of

platelets to stick to each other and also to the surface of a damaged blood vessel wall.















Figure 1: Normal blood film

The platelet count in the circulating blood is normally between 150 and 400 million per millilitre

of blood. Newborn babies have a slightly lower level, but are normally within the adult range by

three months of age.

Many factors can influence an individual's platelet count including exercise and racial origin. The

average life span of a platelet in the blood is 10 days.

What do platelets do?Platelets are essential in the formation of blood clots to prevent haemorrhage - bleeding from a

ruptured blood vessel.

An adequate number of normally functioning platelets is also needed to prevent leakage of red

blood cells from apparently uninjured vessels.

In the event of bleeding, muscles in the vessel wall contract and reduce blood flow. The

platelets then stick to each other (aggregation) and hold on to the vessel wall (primary

haemostasis). The coagulation factors are then activated, resulting in normally liquid blood

becoming an insoluble clot or glue.

What are the risks of a low platelet count?The main effect of a reduced platelet count is an increased risk of bleeding, but this rarelyoccurs until there are less than 80-100 million platelets per ml.

There is not a close relationship between the number of platelets and the severity of bleeding,

but there is an increasing risk of haemorrhage if platelet numbers fall or if platelet function is

impaired (for example by aspirin, which reduces the 'stickiness' of the platelets).

There is a particularly high risk of spontaneous bleeding once the platelet count drops below 10

million per ml. The bleeding is usually seen on the skin in the form of tiny pin-prick

haemorrhages (purpura), or bruises (ecchymoses) following minor trauma.

Bleeding from the nose and the gums is also quite common. More serious haemorrhage can

occur at the back of the eye (retina), sometimes threatening sight.

The most serious complication, which is potentially fatal, is spontaneous bleeding inside thehead (intracranial) or from the lining of the gut (gastrointestinal).

Types of thrombocytopeniaSpecific types of low platelet count include:

idiopathic thrombocytopenic purpura (ITP)

thrombotic thrombocytopenic purpura (TTP)

haemolytic uraemic syndrome.

http://www.netdoctor.co.uk/hearthealth/blood/purpura.htm



http://www.netdoctor.co.uk/diseases/facts/itp.htm


http://www.netdoctor.co.uk/diseases/facts/ttp.htm


http://www.netdoctor.co.uk/diseases/facts/haemolyticuraemic.htm








What causes a low platelet count?The many different causes of thrombocytopenia are detailed below. These causes are not

mutually exclusive and more than one may be responsible for an abnormal platelet count.

Causes summary

False thrombocytopenia Clot in the sample.

Platelets clumped.

Congenital thrombocytopenia

Rare inherited disorders (eg May Hegglin anomaly, Bernard Soulier syndrome).

Defective platelet production

Bone marrow aplasia (failure).

Metabolic disorders, eg kidney failure, alcohol.

Abnormal platelet precursors: viral infections, inherited abnormalities.

Bone marrow infiltration, eg leukaemia, lymphoma.

Diminished platelet survival Antibodies in response to drugs, blood transfusion or another disease, eg glandular fever,

malaria.

Unknown cause (ITP).

Clotting disorder (DIC).

Blood disorder (TTP).

Loss of platelets from the circulation

Massive blood transfusion or exchange.

Enlarged spleen.

Artefactual (false) thrombocytopenia

Some people have platelets that stick together due to the presence of proteins in the blood(antibodies) that bind to the platelets.

These antibodies also bind to a chemical in blood that is tested in the lab, giving a falsely low

platelet count. For this reason, it is helpful to repeat the sample in different tubes with different

chemicals.

The platelet count can also be reduced if the blood sample is difficult to take and the blood clots

- thus using up some of the platelets.

Congenital thrombocytopeniaSeveral rare inherited diseases cause low platelet counts. The severity of the thrombocytopenia

varies with the condition and also the individual patient.

In some of these conditions, eg May Hegglin anomaly, bleeding doesn't happen often.In other inherited diseases, eg Bernard Soulier syndrome, the platelets function less well and

lifelong bleeding symptoms can occur.

Defective platelet productionPlatelets are produced within the bone marrow from cells called megakaryocytes.

If there is a problem in the bone marrow, for example due to abnormal cells, then the number of

megakaryocytes will drop, lowering the number of platelets that can be produced.



Examples of abnormal cells accumulating in the bone marrow include:

acute leukaemia where leukaemic cells, or 'blasts', are seen

other abnormal cancer cells such as lymphoma

more rarely, when cancers develop in another part of the body and have spread

(metastasised) to the bone marrow.

Alternatively, there may be something wrong with the platelet production process itself so notenough platelets are formed.

Impaired platelet production can also be due to:

the side-effects of drugs such as chemotherapy (anti-cancer) agents

viral infections such as HIV

metabolic disorders such as shortage of vitamin B12 or folic acid, kidney failure, alcohol.

an abnormality of the bone marrow called myelodysplasia.

Sometimes platelet production is defective because of an abnormality in the cells that make up

the structural parts of the bone marrow, called the stroma. Examples include:

marble bone disease (osteopetrosis). This hereditary condition causes dense, brittle bones at

the expense of bone marrow. myelofibrosis. This causes a massive increase in the amount of fibrous tissue, which impairs

platelet production as well as the production of other blood cells.

Diminished platelet survivalPlatelet numbers fall if they are removed from the circulation more rapidly than they are

produced.

Platelets are removed for several reasons. They may be coated with an antibody, or are

clumped together and then removed.

Antibodies that cause platelet removal can be due to:

infections such as HIV

medicines such as the anti-malaria drug quinine a specific disease in which abnormal production of other antibodies may occur, eg rheumatoid

arthritis, the skin disease systemic lupus erythematosis or the blood disease chronic

lymphocytic leukaemia.

These antibodies can also occur in someone who is otherwise completely well. This is called

idiopathic thrombocytopinea (ITP) - literally, a low platelet count of unknown cause.

Alternatively, the platelets may be used up if the blood clotting process is inappropriately

'switched on'. This condition is known as disseminated intravascular coagulation (DIC).

DIC can result from the following:

in severe infections such as meningitis.

as a complication of pregnancy or labour, eg high blood pressure and pre-eclampsia in some cancers, specifically types of acute myeloid leukaemia andprostate cancer

in some rare blood disorders such as thrombotic thrombocytopenic purpura or haemolytic

uraemic syndrome (sometimes due to food poisoning outbreaks).

Loss of platelets from the circulation Abnormal distribution of platelets: a low platelet count may be due to a build up of platelets

outside the normal blood pool, for example in a patient with a very large spleen.

http://www.netdoctor.co.uk/diseases/facts/hiv_aids.htm



http://www.netdoctor.co.uk/diseases/facts/prostatecancer.htm

















Dilution of platelets: the platelet count can fall when a patient is transfused with a large

volume of red blood cells that do not contain platelets, because of dilution of normal blood

factors.

How is a low platelet count diagnosed?

Investigation usually starts with a history of symptoms, signs of bleeding or bruising, othermedical problems, recent infections and medications. A blood test is then taken.

In the haematology lab the doctor:

performs a full blood count

examines the blood film under a microscope (see Figure 1)

examines the blood sample in the test tube.

Usually, another full blood count sample is requested to confirm the result and see if it is a

persisting abnormality.

Depending upon the severity of the platelet lack and the likely cause, the person is likely to be

referred to a haematologist at the hospital.

If the platelet count is very low, the person may need to be seen on the same day, and have a

bone marrow test performed.

A bone marrow test is done under local anaesthetic, with samples usually taken from the back

of the pelvis.

This test helps the haematologist to decide if platelets are being produced normally and whether

the rest of the bone marrow appears normal.

Further tests such as genetic tests can also be done on a bone marrow sample.

What treatment is available?The choice of treatment depends upon the severity of the platelet count, its cause and whether

or not there is any bleeding.

Caution In a type of thrombocytopenia called TTP, the use of platelet concentrates is hazardous.

If life-threatening bleeding occurs, eg to the head or bowel, urgent treatment is needed with

platelet concentrates via blood transfusion.

The effect of the concentrates is then monitored by measuring the platelet count and assessing

any continuing bleeding.

The management of acute bleeding also involves treatment of the underlying cause of the low

platelets.

If there is no major bleeding, treatment is aimed at the cause of the low platelet count.



Figure 2: A bag of

platelets for

transfusion

If a drug is thought to be the cause, it should be stopped, providing this is safe, and the platelet

count monitored. If an infection is suspected, treatment of it with antibiotics could be started.

For some infections, especially viral ones such as glandular fever, there is no specific

treatment and close observation may be necessary.

When an infection results in a low platelet count by causing DIC, treatment tackles the

underlying infection and the DIC. Blood components are used to replace the clotting factors

and platelets.

If platelet production fails due to the presence of abnormal or malignant cells, treatment is

directed at those abnormal cells - for example, chemotherapy or radiotherapy would be used in

leukaemia. This can temporarily damage the bone marrow and worsen the thrombocytopenia.

Transfusions would then be given if the platelet count becomes very low until it reaches a safer

level or the bone marrow recovers.

oxygenation new

Documents