Epilepsy (defined as two or more unprovoked seizures) occurs in approximately 0.5% of children. Seizures may be focal (partial) and/or generalised and the aetiology may be idiopathic (genetic) or symptomatic (malformation, tumour, scar, degenerative).

Benign focal (idiopathic partial) epilepsies of childhood

• Onset is typically in mid-childhood (peak 7 years).
  
• Seizures are commonly nocturnal or early morning. In the centro-temporal (Rolandic) variety, they are usually focal motor or sensory phenomena related to the face, mouth or jaw. The occipital variety may have visual manifestations. Secondarily generalised tonic– clonic seizures may also occur.
  
• On EEG, spike discharges typically occur in the centrotemporal or occipital region.
  
• Imaging is only necessary if clinical or EEG features are atypical or if seizure control is difficult.
  
• The prognosis is excellent as the seizures are usually infrequent and remit before the teenage years.
  
• Treatment is only indicated in children with frequent or prolonged seizures. Low-dose carbamazepine or sodium valproate is used for 1–2 years given the spontaneous remission of seizures.

Idiopathic generalised epilepsies

• This term describes a group of recognisable childhood epilepsies characterised by recurrent generalised tonic–clonic, absence or myoclonic seizures of presumed genetic cause.
  
• The first seizure usually occurs at 4–16 years of age, in an otherwise normal child who may have a history of prior FC.
  
• The EEG invariably shows intermittent generalised spike wave patterns.
  
• The prognosis is generally good for seizure control and remission in later childhood or adulthood.
  
• Idiopathic generalised epilepsy syndromes include childhood and juvenile absence epilepsies, juvenile myoclonic epilepsy, and epilepsy with isolated tonic–clonic seizures.

Symptomatic focal epilepsies

• This term describes a heterogeneous group of seizure disorders in which children have focal (partial) seizures from particular brain regions, due usually to an underlying developmental (congenital) or acquired lesion.
  
• Complex partial seizures and focal motor seizures are the main seizure type. The former is usually manifest by arrest of activity, staring, autonomic disturbances, semi-purposeful automatic movements (automatisms) and altered conscious state, sometimes preceded by an aura. Specific seizure manifestations depend on the brain region involved. Seizures may secondarily generalise.
  
• Seizures typically occur in clusters and may be difficult to treat.
  
• Children may have associated learning and behavioural problems, due to dysfunction in the affected brain region or the pervasive effect of uncontrolled seizures and medications.
  
• An EEG may show localised epileptic activity. Structural pathology is sought using MRI.

Symptomatic generalised epilepsies

• These are usually severe seizure disorders affecting infants and young children in which uncontrolled generalised seizures are associated with generalised epileptic disturbances on EEG and global developmental delay or regression.
  
• Examples include West and Lennox–Gastaut syndromes. The characteristic seizures in these syndromes are epileptic spasms (clusters of brief tonic seizures that are usually generalised and in flexion), drop attacks and tonic–clonic seizures, generally difficult to control with medication.

Status epilepticus

See chapter 1, Medical emergencies.

Indications for commencing anticonvulsants

• After the first afebrile seizure, only 1/3 of children experience further episodes. Therefore treatment is not normally commenced unless there are features to suggest an increased risk of recurrence.
  
• Children with absence, myoclonic, complex partial seizures and epileptic spasms have usually had multiple seizures at presentation and require treatment.
  
• It is important to characterise the epileptic syndrome from history, EEG and sometimes imaging. This guides prognosis and the need for treatment.
  
• About 50% of childhood epilepsies have a favourable course from the outset, 25% gradually improve with time, and 25% are refractory to treatment.

The decision to investigate and treat a child following a seizure depends on many factors.

• Children with FC do not generally need EEG or imaging investigation.
  
• An EEG should generally be done in any child with a definite, non-febrile, seizure, whether generalised or partial. EEG aids in the characterisation of seizures and epilepsies, but should not be used to distinguish seizures from nonepileptic events.
  
• Brain imaging is reserved for children with epilepsy in whom there is suspicion from history, examination or EEG that there may be an underlying cerebral lesion. Children with typical forms of uncomplicated and well-controlled idiopathic focal or generalised epilepsy do not require imaging. MRI is more sensitive than CT scan in identifying cerebral lesions, particularly subtle abnormalities of the cerebral cortex.

• Many children referred for assessment of epilepsy do not have epilepsy, but rather a non-epileptic paroxysmal disorder such as syncope, breath-holding spells, parasomnias or non-epileptic staring.
  
• In differentiating epileptic from non-epileptic events, the description of the event is important, including the circumstances in which the event occurred and the details of what the child was doing immediately before the event.
  
• Most non-epileptic paroxysmal disorders can be diagnosed on history alone, or with the aid of a home video recording of a typical event. In some circumstances video-EEG monitoring may be required.
  
• The long Q–T syndrome should be considered in any episode of fainting or seizure that is not clearly due to typical breath-holding, vasovagal syncope or a definable epilepsy syndrome.

The acute onset of symmetrical limb weakness usually has a peripheral neuromuscular or spinal cord origin. Toxins (e.g. snake or tick bite), metabolic disturbance, systemic illness and psychogenic causes need to be considered under appropriate circumstances. Oral polio vaccine is a rare cause of acute flaccid paralysis.

Two key questions require urgent consideration:

• Is there a treatable cause?
  
• Is there respiratory or bulbar dysfunction of sufficient degree to warrant management in an intensive care unit?

Myasthenia gravis

• This diagnosis should be considered in any child with relatively acute-onset limb weakness, particularly if accompanied by ptosis, eye movement disorder, pharyngeal or respiratory insufficiency.
  
• A diagnostic/therapeutic trial of parenteral anticholinesterase is warranted if myasthenia is a possibility.

Guillain–Barré syndrome

• Presents with weakness (ascending progression may be less clear in young children), pain and sensory loss. Weakness may be misinterpreted as ataxia.
  
• The child should be transferred to a tertiary referral centre at the time of diagnosis, as respiratory weakness may occur rapidly
  
• Gamma-globulin or plasma exchange need to be commenced early if they are to be effective.

• Encephalopathies are characterised predominantly (but not exclusively) by cerebral hemispheric dysfunction producing at least two of the following:

– Altered conscious state.

– Altered cognitive state/personality.

– Seizures.

• The onset can be acute, subacute or chronic.
  
• Causes can be grouped into infective (or post-infective), hypoxic, traumatic, epileptic, metabolic, migrainous, raised intracranial pressure and drug or toxin exposure. The primary cause may be systemic or originate in the CNS (see also chapter 30, Infectious diseases, Encephalitis, p. 413).

Examination

Impaired conscious state or cognitive function is the cardinal sign. There may be widespread upper motor neurone signs. Meningism may or may not be present.

Investigations

Investigations are guided by history and examination. Consider the following:

• Electrolytes.
  
• Toxin and metabolic screen.
  
• Cerebrospinal fluid (microscopy and culture; viral and mycoplasma PCR).

Note: For contra-indications to lumbar puncture see chapter 3, Procedures.

• EEG.
  
• Neuroimaging: CT can exclude a mass lesion or acute bleed, but MRI is preferable in most circumstances. MRI of the brain and spinal cord may show multifocal demyelination in acute disseminated encephalomyelitis (ADEM).

Management

• Early specialist referral – early neurosurgical referral if raised intracranial pressure is suspected.
  
• Seizure control.
  
• Identify and treat the primary cause.
  
• Consider empiric antimicrobials e.g. cefotaxime and aciclovir (see chapter 30, Infectious diseases).
  
• If ADEM is suspected, consider high-dose i.v. corticosteroids.

Acute disseminated encephalomyelitis

Acute disseminated encephalomyelitis (ADEM) is a monophasic inflammatory condition of the CNS that most commonly affects children and young adults. The usual presentation is with altered conscious state and multifocal neurological disturbance. It typically occurs following a viral prodrome and has been described following a variety of infections including measles, varicella, EBV, Mycoplasma pneumoniae and non-specific febrile illnesses.

Clinical

• A prodrome of ataxia before onset is typical.
  
• Encephalopathy: may vary in severity from irritability to coma.
  
• Multifocal neurological abnormalities such as ataxia, hemiparesis, optic neuritis, cranial nerve palsies and bladder dysfunction.
  
• A characteristic feature of ADEM is the evolution of symptoms and signs over time: new neurological symptoms and signs appear over the first few days (compared to other types of encephalitis where the onset is usually explosive without new manifestations after 24–48 h).

Investigation

MRI is the investigation of choice and usually demonstrates white matter changes (although grey matter involvement is not uncommon).

Management

General principles as above. Steroids are used in the treatment of ADEM despite the lack of controlled studies to prove their efficacy. Anecdotal evidence of their benefit is now strong. Steroid therapy may improve the patient’s condition but withdrawal of treatment while the disease is still active may result in the return of original symptoms, or the development of new symptoms.

Early studies found a mortality rate of up to 20% with a high incidence of neurological sequelae in those who survived. Recent case reports and small series suggest a more favourable prognosis, with most individuals recovering fully. Residual deficits in higher cognitive function may occur.

• Migraine is the most common identifiable cause of recurrent or chronic headache in childhood.
  
• In adolescence, muscle contraction (tension-type) headache is also common.
  
• Although rare, raised intracranial pressure and systemic illness must also be considered.

History

• Determine the location of the headache and its quality, duration, frequency and time of onset.
  
• Identify trigger factors (food, sleep deprivation), associated symptoms (e.g. nausea or vomiting, visual disturbance and localising or focal symptoms) and the disruption to normal activities.
  
• Inquire whether the symptoms are progressive and if there is a history of recent head injury; development of visual, gait or coordination difficulties; or changes in personality or intellectual functioning; or a family history of migraine or cerebral tumours.
  
• Take a detailed social history.
  
• Consider recording symptoms in a ‘headache diary’.

Distinguishing features

• Tension headache: tends to be persistent but usually does not interfere with sleep.
  
• Migraine: tends to have a fluctuating temporal pattern.
  
• Migraine without aura: usually frontotemporal or bilateral in older children. It is frequently accompanied by nausea and vomiting, followed by lethargy or sleep. Marked pallor is common and there is commonly a positive family history.
  
• Migraine with aura or prolonged neurological symptoms: uncommon in young children.

– Aura is not often reported by young children.

• Intracranial pathology: suggested by recurrent morning headaches; headaches that are intense, prolonged and incapacitating or that show a progressive change in character over time. Other features include abnormal examination findings, unusual migraine description and failure to respond to simple treatment measures. Such patients require urgent specialist referral.

Examination

• Do a thorough neurological examination, including examination of visual acuity and fields, eye movements, optic fundi, coordination and gait. Measure head circumference and blood pressure.
  
• Auscultate the skull for intracranial bruits; palpate over the sinuses, cervical spine and teeth.
  
• Assess the child’s growth and pubertal status; inspect the skin for neurocutaneous stigmata.

Management of migraine

• Reassure the child and parents that migraine is not usually a serious condition.
  
• In an acute attack, all that is usually required is trigger avoidance, stress management and the early use of paracetamol 15 mg/kg per dose orally, 4 hourly (max. 90 mg/kg per 24 h). NSAIDs (e.g. ibuprofen 2.5–10 mg/kg per dose (max. 600 mg) oral 6–8 hourly) can also be useful. The role of sumatriptan in childhood is not yet clear. In children with severe vomiting and oral agents are not tolerated, metoclopramide and chlorpromazine can be used.
  
• Prophylactic therapy for those with severe or frequent attacks is best used in consultation with a specialist. Propranolol or pizotifen are commonly used. Sodium valproate, cyproheptadine, verapamil, clonidine and amitriptyline can also be effective in some children.
  
• 2/3 of children cease having attacks but 50% of these have recurrences in adult life.

Craniosynostosis is an uncommon disorder of childhood affecting 4/10 000 children. It is a condition of premature fusion of the cranial sutures resulting in an abnormal head shape.

• The resulting head shape depends on which suture fuses. The common shapes are:

– Scaphocephaly (sagittal suture).

– Brachycephaly (coronal suture).

– Plagiocephaly (lambdoid suture). Most children with plagiocephaly have a postural deformation rather than craniosynostosis.

• The main problem is cosmetic. Only a small proportion have raised intracranial pressure.

Management

• Frank sutural synostosis requires surgical correction.
  
• Postural lambdoid plagiocephaly is not associated with sutural fusion and does not require surgery. It may partially correct spontaneously with changes in sleeping position. The asymmetric head shape becomes less obvious with hair growth.

Background

• Although considered rare by adult standards, childhood stroke is more common than brain tumours and amongst the top ten causes of death in childhood.
  
• Subtypes include arterial ischaemic stroke (AIS), cerebral sinovenous thrombosis (CSVT) and haemorrhagic stroke (HS).
  
• Mode of presentation, risk factors, aetiology, recurrence rates and outcome are dependent on stroke subtype and age.
  
• Neuroimaging is required to confirm the diagnosis and to differentiate from other paroxysmal neurological disorders.

Aetiology

• Arteriopathies – transient (e.g. post varicella, dissection) or progressive (e.g. Moya Moya disease) in AIS.
  
• Congenital heart disease in AIS and CSVT.
  
• Thrombophilias in AIS and CSVT.
  
• Head and neck/ENT infections in CSVT.
  
• Metabolic.

Clinical features

• Neonates: commonly present non-specifically with seizures, lethargy and apnoea. Focal neurological signs are rarely evident.
  
• Older infants: typically present with congenital hemiplegia, early hand preference and lateralised neurological deficits.
  
• Patients with CSVT: commonly present non-specifically with seizures and signs of raised intracranial pressure.

Diagnosis

• Urgent imaging:

– CT head – sufficient to exclude haemorrhage (but may potentially miss AIS or CSVT).

– MRI or MRA head – if not done immediately should be done <48 h.

• ECG and transthoracic echocardiogram:

– To look for structural heart defects and patent PFO with paradoxical embolisation.

• Prothrombotic work-up:

– Preferably taken before anticoagulation.

– Includes antithrombin, protein C, protein S, plasminogen, activated protein C resistance (APCR), prothrombin gene 20210A, anticardiolipin antibody (ACLA), lupus anticoagulant, serum homocysteine.

Management

General management

• Measures that improve outcome in adults include correction of fever, maintaining normal glycaemia, normal blood pressure.
  
• Oxygen – to keep SaO2 >95% through first 24 h.
  
• Close observations – initially hourly neurological observations.
  
• Keep nil by mouth until assessment by speech pathologist.
  
• If seizures, load with i.v. phenytoin (or phenobarbitone in neonates).
  
• Rehabilitation: early referral should be made once the child is stable.

Acute antiplatelet/anticoagulant treatment should be discussed with the neurologist and haematologist on call.

For neonates with AIS

• Aspirin or anticoagulation for 6–12 weeks is recommended for neonates with cardioembolic AIS.
  
• Do not use anticoagulation or aspirin for non-cardioembolic AIS unless there are recurrent events.

For children with AIS

• Initial treatment with aspirin, 1–5 mg/kg per day, unfractionated heparin (UFH) or lowmolecular-weight heparin (LMWH) for 5–7 days while being investigated for cardioembolic sources and vascular dissection.
  
• Treatment should be continued with LMWH or warfarin for another 3–6 months if dissection or cardioembolic source is confirmed.
  
• Conversion to aspirin, 1–5 mg/kg per day is recommended for all other children for a minimum of 2 years.

For children with CSVT

Anticoagulation is usually recommended, except if associated with a significant haemorrhage, patient is hypertensive or other risks for bleeding are present.

• For CSVT without significant intracranial haemorrhage:

– Initially with UFH or LMWH.

– Subsequently with LMWH or warfarin for a minimum of 3 months (neonates 6 weeks to 3 months).

• For CSVT with significant intracranial haemorrhage:

– Radiological monitoring at 5–7 days and anticoagulation if thrombus propagation occurs.

Assessment