Febrile seizures: Viva

Branch 1: Definition and classification

The candidate should confirm the diagnosis by stating the four locked criteria: a convulsion with fever over 38 degrees Celsius in a child aged 6 months to 60 months, without a central nervous system infection and without a prior afebrile seizure. This girl meets all four, so she has had a febrile seizure. A strong candidate then classifies it as complex rather than simple, because it lasted 18 minutes, which is over the 15 minute boundary. The duration alone makes it complex, and the candidate should explain that the simple-versus-complex split drives the workup, the counselling, and the prognosis. ^[1]

If the examiner presses on the boundaries, the candidate should explain that 15 minutes is the point at which a convulsion is unlikely to self-terminate and active treatment should begin, and that 30 minutes defines febrile status epilepticus. The candidate should note that a convulsion still ongoing at five minutes is heading toward status and should be treated, not observed. The FEBSTAT study linked febrile status epilepticus to acute hippocampal injury and to later temporal lobe epilepsy, which is why duration is a classification feature and not merely a descriptor. ^{[1] [4]}