SEIZURES

  Def:  Paroxysmal involuntary disturbance of brain function, manifested by abnormal motor activities, sensory disturbance, autonomic dysfunction or behavioral abnormalities.

 1- Febrile convulsions  2- First epileptic fit.  3- Metabolic:   Hypo (glycaemia, calcaemia, magnesaemia).   Hypo or hypernatraemia.   Pyridoxine (B6) deficiency.

 4 CNS causes:   Infection: Meningitis, encephalitis and brain abscess.   Irritation: Brain oedema.   Tumours of the brain.   Toxic: e.g. tetanus or drugs (aminophylline and antihistamincs).   Hge: Trauma, rupture aneurysm and Hgic blood diseases.   Hypoxia: Asphyxia, apnea, ……..   Hypertensive encephalopathy, uraemic encephalopathy, ……..

 B- Recurrent convulsions  1- Recurrent febrile convulsions.  2- Epilepsy & conditions mimic epilepsy.  3- Tetany.

 4- Chronic metabolic causes:   Recurrent hypoglycaemia (Hyperinsulinism, hypopituitarism, glycogen storage diseases).   Uraemic encephalopathy (CRF).   Hepatic encephalopathy.   Inborn errors of metabolism (Phenyl ketonuria, hyper-ammonaemia, maple syrup urine disease, …..) syrup urine disease, …..)

FEBRILE CONVULSIONS   Def:  Convulsions in children due to rapid increase of body temperature due to extracranial cause (e.g. tonsillitis, pneumonia, …)   Incidence:   4% of children.   Family history in about 20% of cases.

  Diagnosis:  1- Age: 6 months  5 years (convulsions below 6 months or above 5 years are not  considered febrile).  2- Temperature: usually > 39  convulsions occur within 8-12 hours from the onset of fever.  3- No evidence of CNS infection: e.g. meningitis, abscess, ….  4- Evidence of extracranial infection: e.g. sepsis, tonsillitis, ……

5- Types of convulsions:  A- Simple febrile convulsions:   The most common form.   Usually generalized tonic – clonic.   Short duration (<15 min.).   Usually one fit only during 24 hours.  B- Complex febrile convulsions:   Uncommon.   May be focal.   Prolonged duration.   Fits may recur during the same illness.

 6- Investigations:  Not needed, but complex form may be mistaken with CNS infection, so CSF is done in doubtful diagnosis.  7- D.D.:  Other causes of convulsions.

  Treatment:  1- Control of convulsions: Diazepam mg/Kg (I.V. or rectally).  2- Measures to lower body temperature:  Cold backs or baths.  Antipyretic drugs.  3- Treatment of the underlying cause e.g. antibiotics.  4- Prophylactic anti-convulsant therapy e.g. Na valproate.  Not indicated except in recurrent attacks (esp. complex form).

  Prognosis:   Recurrence rate about 25%.   The risk for developing epilepsy is increased with:   Family history of epilepsy.   Pre-existing neurological disease.   Complex form.

EPILEPSY   Def.:  Recurrent seizures not related to fever or acute brain insult.   Aetiology:  1- Idiopathic (1ry): 80% of cases either hereditary or not.  2- Organic (2ry): 20% of cases, may be:   Congenital cerebral malformation.   Degenerative brain diseases.   Post-traumatic.   Post-hgic.   Post-infection.   Post-toxic.   Post-anoxic.

  Classification:  1- Focal (partial) seizures:   Only one part of the body is involved (focal).   Only one type of movements (tonic or clonic).   It has 3 types:  a- Simple partial seizures (SPS (  b- Complex partial seizures (CPS)  c- Partial seizures with 2ry generalization

 2- Generalized seizures:   Affect the whole body from the start.   Classified into:  a- Absence seizures (petit mal):   Sudden cessation of all motor activities and speech (Awareness of  the surroundings is cut off).   Precipitated by hyperventilation or photic stimulation.   Rarely persists more than 30 seconds (but frequently recurrent).   Usually not associated with loss of consciousness.   No aura.   No post-ictal phase.

 b- Generalized tonic-clonic seizures (Grand- mal): The commonest type, passes into 3 phases: passes into 3 phases:  1- Aura (pre ictal): Before the attack as a warning sign which may be motor  (localized muscular spasms), sensory (parasthesia) or autonomic (intestinal pain).  2- Attack (Ictal):  Sudden loss of consciousness (not more than 10 min).  Tonic phase: Rigid posture with rolling of the eyes, drooling of saliva, clinching of the teeth and incontinence to urine and stool.  Clonic phase: Rapid relaxation and contraction of muscles (clonic motor activity).  3- Post ictal phase: Headache, sleep or Todd’s paralysis.

 c- Myoclonic epilepsy:  Sudden shock like repetitive contractions of group of muscles.  d- Infantile spasms:  Repetitive tonic contractions of the neck and trunk muscles which occur in the first year of life and carry a poor prognosis  e- Atonic seizures:  Sudden loss of body tone and falling down.

  Investigations:  1- Electro-encephalo-gram (EEG): must be done for all cases (despite it is -ve in 40%).  2- CT scan or MRI brain: indicated in: focal lesions (e.g. hge), resistant to ttt evidence of  ICT.  3- CSF: Only indicated in suspected CNS infection.  4- Metabolic screen: Na, K, Ca, Mg, ……. (to exclude metabolic causes).

  D.D:  1- Of causes of recurrent convulsions esp. conditions mimic epilepsy which are:   Syncopal attacks.   Breath-holding attacks.   Rage attacks.   Paroxysmal vertigo.   Pseudo-seizures.  2- D.D. of the cause (Idiopathic or 2ry ….)

  Treatment:  I- INBETWEEN THE ATTACKS:  1- Moderation of activities and avoidance of the predisposing factors.  2- Health education of the parents about the disease and advise them to watch  their child during swimming, running, passing the traffic, ….  3- Drug therapy:   Only one drug is used in low dose then slightly  if no response.   If still no response 2nd drug may be tried either alone or in combination with the  first drug.   Duration of therapy is at least for 2 years after the last attack.

 General side effects of anti-epileptics are: 1.  Drowsiness 2.  Ataxia 3.  GIT disturbances (except Phenobarbitone)

 II- DURING THE ATTACK:  1- General: O2 and suction of secretions.  2- Drugs:  Diazepam mg/kg/I.V.  if no response    Phenobarbitone mg/kg/I.V.  if no response    Phenytoin mg/kg/I.V.

 III- STATUS EPILEPTICUS  Convulsions lasting more than 30 minutes or repetitive convulsions without return of consciousness.  1- Admission to ICU.  2- ABC  Airway (keep patent airway with suction of secretions.  Breathing (O2  bag and mask ventilation  pulse oxymetry for O2 saturation).  Circulation (IV access, IV fluids & blood samples for electrolytes).

 3- Drugs   Diazepam (if no response)  phenobarbitone (if no response)  phenytoin (if no response)  Diazepam continuos infusion (if no response)  paraldehyde I.V. (if no response)  General anaesthesia.