urine analysis 1- physical examination 2- chemical examination 3- microscopic examination 4-...

Urine Analysis

1 -Physical Examination2 -Chemical Examination

3 -Microscopic Examination4 -Microbiological Examination

Collection of Urine for Analysis

• Urine is collected over a period of 24 hours.

• A preservative (as toluene, chloroform, thymol & formalin) is added to prevent contamination of the urine

• keeping urine in refrigerator is greatly

advisable especially in hot weather.

Urine Analysis

1

2

3

1 -Volume2 -Specific Gravity

3 -Aspect4 -Color5 -Odor

6 -Deposit7 -Reaction (pH)

URINE ANALYSISPhysical Examination


1- Volume: Normal urine volume in 24 hours is 600-2000 ml 1- Urine volume increases (Polyuria) in the following conditions:

Physiological: Increased fluid intake Diuretic

Pathological: Diabetes mellitus (type-1 & type-2) Diabetes insipidus (due to decrease of ADH) Chronic renal failure 2- Urine volume decreases (Oliguria or anuria) in the following

conditions: Dehydration Acute renal failure Obstruction

2- Specific gravity (SG): • Specific gravity measures solute concentration (urea and

sodium). • Normally the specific gravity ranges between 1.015-1.025. 1- Increased in • Dehydration (with oliguria)• Diabetes Mellitus (with polyuria)• Acute renal failure (with oliguria) 2- Decreased in • Diabetes insipidus (with polyuria)


3- Appearance:

Normal fresh urine: clear (transparent) Abnormal : Cloudy urine may indicate possible abnormal constituents such as white cells, epithelial cells, crystals and bacteria.

N.B. Stored urine with no preservative & no cooling may turn clear urine samples into cloudy.


4- Color: Normal color: pale yellow (amber yellow)due to the presence of pigments of urobilin or urobilinogen

Abnormal colors of urine:• Colorless• Orange• Greenish yellow• Red• Black• Smoky


Color (cont.)

1- Colorless Urine:

Chronic renal failure Diabetes insipidus.

2- Orange Urine:

Ingestion of large amount of carotenoids (vitamin A)

3- Yellowish brown urine: due to presence of billirubin in cases of:

• Obstructive Jaundice • Hepatic Jaundice


Color (cont.)

4- Red urine: due to presence of blood, hemoglobin & RBCs.

5- Black urine:

Methemoglobin Homogentisic acid in alkaptonuria Malignant malaria (black water fever due to Malaria

falciparum). Melanin (melanoma) 6- Smoky urine:• presence RBCs. in the urine, in cases of acute glomerulonephritis


5- Odor:

Normal Urineferous odor: The normal odor of fresh voided urine sample

Abnormal Odors

1- Fruity odor due to presence of acetone in the urine as in diabetic

ketoacidosis 2- Ammonia odor due to release of ammonia as result of: the bacterial action on urea in the contaminated urine or long standing exposed urine samples.


6- Deposits: • Normally the urine is devoid of deposits. • The presence of deposits is mainly due to

various types of crystals, salts and cells.


7- Reaction (pH):

Normally: The pH of urine varies from 4.6 - 8.0

1- Acidic urine:• Large intake of meat & certain fruits (cranberries)• Metabolic & respiratory acidosis

2- Alkaline urine: • Vegetarians• Metabolic & respiratory alkalosis• Urinary tract infection by urea splitting bacteria which

split urea to ammonia (alkaline)


Normal Constituents of UrineNormal urine contains about 50g of solids dissolved in about 1.5 liters of water per day. Urine contains organic and inorganic solids. A) Chief Inorganic Solids

• Sodium, potassium & chlorides • Smaller amounts of calcium, magnesium, sulfate & phosphates• Traces of iron, copper, zinc and iodine.• B) Chief Organic Solids:

1- Non-protein nitrogen:

• amino acids, ammonia, urea, uric acid , creatine & creatinine

2- Organic acids:

• lactic acid, citric acid & oxalic acid• ketone bodies (few amounts)

3- Sugars:

• Normally not more than 1g of sugars is excreted in the urine per day. • Sugars cannot be detected by ordinary tests. • Very small amounts of glucose not exceeding 150 mg of glucose are normally excreted

per day. • Other sugars present in urine are: pentose and lactose .• Lactosuria occurs in infant and in women during the late months of pregnancy and

during lactation

URINE ANALYSISChemical Examination

Abnormal Constituents of Urine

1- Proteins (proteinuria)2- Sugars (glucosuria, fructosuria & galactosuria) 3- ketone Bodies (ketonuria)4- Billirubin (billirubinuria) & Bile Salts5- Nitrites


1- Proteins: (proteinuria)

Proteinuria Presence of more than 150 mg proteins in urine

in 24 hours detected by ordinary laboratory means

heavy proteinuria : ＞ 4 gm/24 hours moderate proteinuria: 1 - 4 gm/24 hours minimal proteinuria: ＜ 1.0 gm/24 hours


1 -Proteins: (proteinuria)

Proteinuria is divided into prerenal, renal and postrenal proteinuria.

1-Prerenal proteinuria:

• Bence-Jones protein: This abnormal gamma globulin (light chains only) is synthesized by malignant plasma cells (multiple myeloma). It precipitates at 60oC, redidssolves at 100oC and reprecipitates on cooling. 2-Renal proteinuria:

• Severe muscular exercise • After prolonged standing• Acute glomerulonephritis • Nephrotic syndrome

3- Postrenal proteinuria:

• Lower urinary tract inflammation, tumors or stones.


2 -Sugars: (glycosuria) Glucose (Glucosuria);

Presence of detectable amount of glucose in urine which occurs in the following conditions:

- Uncontrolled Diabetes Mellitus (DM) - Renal glucosuria with lowering of renal threshold : e.g. during pregnancy (gestational diabetes).

Fructose (Fructosuria):

Presence of fructose in urine & may be due to :- -Alimentary causes following the ingestion of large amounts of fructose

Fructosemia & herditary fructose intolerance (Metabolic disorders of fructose.)

Galactose (Galactosuria):

Presence of galactose in urine& may be due to :- Alimentary causes following the ingestion of large amount of galactose. - Galactosemia


3- Ketone Bodies (Ketonuria): Presence of acetone, acetoacetic acid and β hydroxybutyric acid in urine due to:

• Diabetic ketoacidosis (uncontrolled DM)• Starvation• Unbalanced diet: high fat & low carbohydrates

diet.


4- Bilirubin (bilirubinuria) Billirubin appears in urine in cases of:

• Hepatocellular Jaundice: as in viral hepatitis • Obstructive Jaundice as any cause of obstruction of bile duct


5- Nitrites• In bacteruria in urine (in cases of

Urinary Tract Infection, UTI)


MICROSCOPIC URINE EXAMINATION

• Specimen of Choice:First morning , midstream, clean catch urine specimen. This specimen is preferred since it is most concentrated and thus small amounts of abnormal constituents are more likely to be detected

• Procedure: 1- By pouring the urine sample into a test tube & centrifuging it (spinning it down in a machine) for a few minutes.

2- The top liquid part (the supernatant) is discarded.

3- The solid part left in the bottom of the test tube (the urine sediment) is mixed with the remaining drop of urine in the test tube and one drop is analyzed under a microscope.

Urine is examined microscopically for:

1- Cells 2- Casts 3- Crystals 4- Parasitic ova .


MICROSCOPIC URINE EXAMINATIONCells

Red Blood Cells (RBCs)

Normally: < 3 RBCs / HPF

Hematuria is the presence of abnormal numbers of red cells in urine

Types of Hematuria:

1 -Gross hematuria

Means that the blood can be seen by the naked eye .

The urine may look pink, brown or bright red.

2 -Microscopic hematuriaMeans that the urine is clear, but blood cells can

be seen when urine is examined under microscope.

Causes of hematuria:• Glomerular damage : as in acute glomerulonephritis• Tumors• Urinary tract stones• Upper & lower urinary tract infections


White Blood Cells (WBCs)

Normally : WBCs: < 5 cells / HPF

Pyuria (Pus in Urine)Refers to the presence of abnormal numbers of WBCs that may appear with:

-Urinary tract Infection : upper or lower

-Acute glomerulonephritis

-Acute pyelonephritis

Repeated sterile cultures in presence of pyuria may indicate:-The patient is on antibiotic therapy-The presence of an organism that does not grow on ordinary media as T.B.-Non- bacterial urethritis or cystitis as viral infection


Epithelial Cells

• Renal tubular epithelial cells contain a large round or oval nucleus & normally slough into the urine in small numbers.

• The number sloughed renal epithelial cells is increased in: - Nephrotic syndrome (Glomerular) - Renal tubular degeneration (Tubular)


Casts

Acellular casts• Hyaline casts• Granular casts• Waxy casts• Fatty casts• Pigment casts• Crystal casts

Cellular casts• Red cell casts• White cell casts• Epithelial cell cast

Types of Casts

Urinary casts are formed only in the distal convoluted tubule (DCT) or the collecting duct.

MICROSCOPIC URINE EXAMINATIONCasts

Hyaline casts

• Hyaline casts composed of a mucoprotein (Tamm- Horsfall protein) secreted by tubular cells.

Hyaline casts cont.

The factors which favor protein cast formation are:• Low flow rate• High salt concentration• Low pHAll of which favor protein denaturation and precipitation.

Protein casts with long thin tails formed at the junction of Henle's loop and the distal convoluted tubule are called cylindroids.

Hyaline casts are seen in 1- Healthy persons 2- Physiological (as in fever, strenuous exercise) 3- Glomerular damage (as in nephrotic syndrome)


Hyaline casts cont.

Granular casts• Granular casts can result either from the breakdown of

cellular casts (if persist for long duration in tubules) resulting in appearance of aggregation of contents of cells without the cell membranes

• Or result from the inclusion of aggregates of plasma proteins (e.g. albumin) or immunoglobulin light chains to a hyaline cast

• indicative of chronic renal disease


Granular casts


Waxy casts

Waxy casts• Suggest severe longstanding kidney disease such as

renal failure (end stage renal disease)• They may appear as an advanced stages of granular

casts


Casts

Fatty castsFormed by the breakdown of lipid-rich epithelial cells, these are hyaline casts with fat globule inclusions

They can be present in: • Nephrotic syndrome (due to cholesterol increase in urine)• Diabetic or lupus nephropathy• Acute tubular necrosis (damage of tubular cells with release

of fat contents into hyaline casts)

Red Blood Cells CastsRed blood cells may stick together and form red blood cell casts.

RBCs casts are indicative of:1- Glomerulonephritis with leakage of RBC's from glomeruli 2- Severe tubular damage


Red Blood Cells Casts

White blood cell casts

Indicate inflammation of the kidney as such casts will not form except in the kidney

1- Acute pyelonephritis (most common cause)2- Glomerulonephritis.


White blood cell casts


Epithelial casts

Epithelial casts

This cast is formed by inclusion or adhesion ofdesquamated epithelial cells of the tubule lining the castsThese can be seen in Acute tubular necrosis

http://en.wikipedia.org/wiki/Acute_tubular_necrosis



MICROSCOPIC URINE EXAMINATIONCrystals

Crystals in acidic urine

Uric acid Calcium oxalate Cystine Leucine

Crystals in alkaline urine

Ammonium magnesium phosphates (triple phosphate

crystals) Calcium carbonate

Uric AcidCrystals

Triple PhosphateCrystals

Calcium Oxalate Crystals

CystineCrystals

MICROSCOPIC URINE EXAMINATIONCrystals

crystals

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urine analysis 1- physical examination 2- chemical examination 3- microscopic examination 4-...

Documents

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black urine

cloudy urine

alkaline urine

colorless urine

contaminated urine

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