Headache• Definition : A headache involves pain in the

head which can arise from many disorders or may be a disorder in and of itself.

• There are three types of primary headaches: tension-type (muscular contraction headache), migraine (vascular headaches), and cluster

• Headaches may result from contraction of the muscles of the scalp, face or neck; dilation of the blood vessels in the head; or brain swelling that stretches the brain's coverings

Drowsiness

• Definition : a decreased level of consciousness characterized by sleepiness and difficulty in remaining alert but easy arousal by stimuli.

• It may be caused by a lack of sleep, medications, substance abuse, or a cerebral disorder.

Cerebrospinal fluid

• Major function :Shock-absorbing fluid to prevent brain from

bumping against the interior of the hard skull when head is subjected to sudden, jarring movement

Exchange of materials between neural cells and interstitial fluid surrounding the brain

Materials exchange freely between CSF and interstitial fluid rather than between blood and brain interstitial fluid.

CSF production• By choroid plexuses :o Found in particular region of ventricleso Richly vascularized, cauliflower-like masses of

pia mater tissue that dip into pockets formed by ependymal cells

o Formed as result of selective transport mechanisms across the membrane

o Compared to blood : Low K+ and higher Na+

(ideal concentration gradient) for conduction of nerve impulse and almost no protein

CSF circulation• Flows through 4 interconnected ventricles and

through spinal cord narrow central canal (continuous with last ventricles)

• Escapes through small opening from 4th ventricles at the base of brain to enter subarachnoid space and flows between meningeal layers

CSF reabsorption

• At upper regions of brain, reabsorbed from subarachnoid space into venous blood through arachnoid villi

• Facilitated by ciliary beating along with circulatory and postural factors result in CSF pressure of 10mmHg

• Reduction of pressure by removal of few ml of CSF will cause headache

• CSF volume : 125-150ml replaced 3x a day

Lumbar Puncture• Landmarks : plane of iliac crest through L4. in adults,

spinal cord ends at L1,2 disc.

• CSF findings :

3. Bloody tap – artefact due to piercing of blood vessel, if RBC reuced in subsequent bottle and no xanthochromia

4. Subarachnoid haemorrhage – yellow CSF (xanthochromia), same RBC amount in all tap

5. Very raised CSF protein – spinal block; TB; severe bacterial meningitis

6. Raised protein – meningitis; MS; uremia; hypothyroidism; DM; Guillain-Barre

Seizures

Seizure first aid1. Stay calm2. Prevent injury

During the seizure, you can exercise your common sense by insuring there is nothing within reach that could harm the person if she struck it.

3. Pay attention to the length of the seizure

4. Make the person as comfortable as possible

5. Keep onlookers away6. Do not hold the person down

If the person having a seizure thrashes around there is no need for you to restrain them. Remember to consider your safety as well

1. Do not put anything in the person's mouthContrary to popular belief, a person having a seizure is incapable of swallowing their tongue so you can breathe easy in the knowledge that you do not have to stick your fingers into the mouth of someone in this condition.

2. Do not give the person water, pills, or food until fully alert

3. If the seizure continues for longer than five minutes, call 911

4. Be sensitive and supportive, and ask others to do the same

5. After the seizure, the person should be placed on her left side. Keep in mind there is a small risk of post-seizure vomiting, before the person is fully alert. Therefore, the person’s head should be turned so that any vomit will drain out of the mouth without being inhaled. Stay with the person until she recovers (5 to 20 minutes).

Causes of optic disc swelling• Raised intracranial pressure: papilledema

• This may be due to :

obstruction of the ventricular system, space-occupying lesions, impairment of CSF absorption, diffuse cerebral oedema or idiopathic (benign/essential) intracranial hypertension. Some medications have been associated with this, e.g. tetracycline,minocycline, lithium, isotretinoin, nalidixic acid and corticosteroids (both use and withdrawal).

• Presentation: headache (worse on waking and when coughing), may have nausea/vomiting and may have other neurological symptoms.

Glasgow Coma Scale1 2 3 4 5 6

Eyes Does not open eyes

Opens eyes in response to painful stimuli

Opens eyes in response to voice

Opens eyes spontaneously

N/A N/A

Verbal Makes no sounds

Incomprehensible sounds

Utters inappropriate words

Confused, disoriented

Oriented, converses normally

N/A

Motor Makes no movements

Extension to painful stimuli (decerebrate response)

Abnormal flexion to painful stimuli (decorticate response)

Flexion / Withdrawal to painful stimuli

Localizes painful stimuli

Obeys commands

The scale comprises three tests: eye, verbal and motor responses. The three values separately as well as their sum are considered. The lowest possible GCS (the sum) is 3 (deep coma or death), while the highest is 15 (fully awake person).

Incidence & Aetiology

1. Neonates (HS 2)

• Infected during delivery to a woman with active genital herpes

2. Adults (HS 1)

• Infected through bloodstream from minor focus of viral replication, usually in mouth.

3. Immunocompromised person

• Undergoing chemotherapy for Rx of cancer

Pathology

• Virus reaches brain via blood stream• Infects brain cells, causing neuronal necrosis and

marked cerebral edema, lead to acute cerebral dysfunction and increased ICP

• Perivascular lymphocytic infiltration (perivascular cuffing)

• Severe cases, hemorrhage occur• Herpes simplex encephalitis affects the temporal

and inferior frontal lobes selectively• Producing necrotizing , hemorrhagic acute

encephalitis may rapidly cause death• Pts who survive, suffer permanent neurological

defect, depends on neuronal loss

Clinical features

• Acute onset of fever, headache, sign of brain dysfunction

• Convulsion may occur

• Papilledema if cerebral edema is severe

• Concomitance meningeal inflammation causing neck stiffness and CSF abnormalities

Diagnosis

• Brain biopsy – shows cerebral edema, necrosis, lymphocytic infiltration, presence of intranuclear Cowdry A inclusions in infected cells

• Electron microscopy / in situ hybridization tests – demonstrate the virus protein

Treatment - Acyclovir• is a guanosine analogue that disrupts HSV

DNA synthesis

• MOA :

Notifiable diseases in Malaysia

Bacterial Virus Other / Multiple

Cholera AIDS Dysentery

Diphteria Dengue fever Malaria

Encephalitis Hepatitis

Gonorrhea HIV infection

Leprosy Measles

Parathyphoid fever Poliomyelitis

Pertussis Rabies

Plague Yellow fever

Relapsing fever Viral hemorrhagic fever

Rickettsiosis

Syphilis

Tetanus

Tuberculosis

Typhoid fever

Typhus