Explanation

The most common causes of sudden loss of consciousness followed by rapid recovery in a previously normal infant are seizures and breath-holding attacks. If the episode was a seizure, the cause has to be established. At this age a febrile seizure is the most common cause but other considerations include hypoglycaemia, metabolic disorders, intracranial infection, vascular disease, structural abnormalities of the brain and the first presentation of epilepsy. In older children with syncopal episodes, there is sometimes brief limb jerking (convulsive syncope), which may be misinterpreted as an epileptic seizure. Cardiac causes are very rare but should be considered, particularly if the seizure was associated with exertion or palpitations.

The key to correct diagnosis is a detailed systematic history of events before, during and after the event.