First seizure and seizure mimics — structured clinical encounter

A nine-year-old girl is referred to your general paediatric clinic after a five-minute generalised tonic-clonic seizure at home, witnessed by her mother. The mother describes a brief odd smell, then a cry, loss of awareness, symmetrical stiffening of all four limbs followed by rhythmic jerking, cyanosis, urinary incontinence and a lateral tongue-bite, then fifteen minutes of confusion and drowsy sleep before she returned to normal. There is no fever, no recent head injury, and no family history of epilepsy. She is developmentally normal, plays sport, and is on no medication. On examination she is back to her baseline, with a normal neurological examination, no neurocutaneous stigmata, a normal head circumference and a normal cardiovascular examination including a regular pulse with no murmur.