Untreated recurrent acute necrotising encephalopathy associated with RANBP2 mutation, and normal outcome in a Caucasian boy.

Acute necrotising encephalopathy (ANE) is a rare encephalitis-like syndrome usually reported in East Asia. This clinical syndrome tends to be triggered by viral febrile illness with rapid deterioration to seizures, coma and a generally poor outcome. Diagnosis is usually made on Magnetic Resonance Imaging (MRI). Its epidemiology is unknown largely due to under-recognition. Recurrent ANE has recently been associated with a newly discovered autosomal dominant mutation RAN-binding protein 2 now termed ANE1. There had been reports encouraging the use of empirical corticosteroids as treatment for this condition. However, there have not been any clinical trials to date. Here we report an unusual case of a Caucasian toddler who had suffered two episodes of ANE, but did not receive any specific treatment and has normal physical and cognitive outcome at 1 year follow up. He has this missense mutation in the gene of the RAN-binding protein 2 as have his mother and brother who are both well. This case adds to the worldwide literature and expands on the spectrum of outcomes in order to bring about better recognition in the Caucasian population.