FIRES initial phase
By Jacques Emmery, General Practitioner, “Order of Tarn’s doctors”’ vice-president
In FIRES or DESC, if the first seizure appears in a classic context (common convulsion in a healthy child aged between 4 and 10 with a single spiking fever and without any signs of infection), then repetition of seizures increases with very different consequences: chewing, lateral deviation of the head and eyes, heart rate modification (usually decrease or bradycardia), plain or bilateral dilatation of the pupils (mydriasis), muscle spasms of the face or in an arm or a leg.
Quickly, it turns in generalised “tonic-clonic” seizures and between seizures, the child can be sleepy or in a coma which can be more or less severe.
Recording a seizure with an electroencephalogram (EEG) shows that electric shocks occur all over the brain. Between seizures, EEG shows diffuse slow-waves usually seen in encephalitis (inflammatory brain infection), which can provoke confusion in FIRES or DESC diagnosis.
However, Magnetic Resonance Imaging (MRI) makes a difference in the diagnosis. An MRI would not show any abnormal imaging of brain structure (grey matter and white matter) contrary to what is seen in encephalitis. On the other hand, an MRI can show hippocampus damage (2 small organs in the middle of the brain which are central places of memory) which will hasten the diagnosis of FIRES or DESC.
Other indicators that confirm FIRES diagnosis :
- status epilecticus resisting to all antiepilecptic treatments, even the strongest ones
- negative biologic investigations for inflammatory markers and auto-antibodies usually found in some encephalitis
- normal appearance of cerebrospinal fluid taken by lumbar puncture
- the number of daily seizures in the initial phase, which can be higher than 100
- and after that, the status epilepticus period which can average 30 days and sometimes continue for 60 days or more.
So the only solution to overcome this critical stage is a deep general anesthetic including curariform drugs that have an effect on all muscles and breathing muscles. This requires breathing assistance first with tracheal intubation by the nose then by tracheotomy after 2 or 3 weeks of breathing assistance.
However, when the anaesthetic is stopped, seizures usually return (less frequently and less severe) despite of the harsh antiepileptic treatment.