G398(P) A Rare demyelination disease: neuromyelitis optica

Abstract

Introduction Neuromyelitis optica (NMO) is an inflammatory autoimmune disease of the central nervous system, accounting for 1.6% of paediatric demyelinating diseases in the UK. The limited literature suggest an incidence globally of 0.053 to 0.4 per 1 00 000 per year with wide geographical variation and the average age of presentation reported from 7 to 10.2 years. This case report describes the presentation, diagnosis and management of NMO in a 7-year-old girl in the UK. Case report A previously fit and well 7-year-old girl was referred with a two days history of falls and eye discomfort accompanied with significant pruritis for the last two weeks. She had also had a recent admission for severe, intractable vomiting requiring TPN with no conclusive diagnosis. On initial assessment, there was right-sided weakness, globally brisk reflexes and ataxia with bilateral pupillary dilatation and reduced visual acuity. The patient was hypertensive at 150/98 and was admitted to HDU for close monitoring. An initial MRI head suggested possible optic nerve inflammation. Her weakness progressed to affect all 4 limbs (more on the right side), concurrent urinary retention and complete visual loss over 48 hours. Subsequent to paediatric neurology assessment, a likely diagnosis of NMO was made. On day 4 of admission, a three days course of high dose methylprednisolone (30 mg/kg) was commenced. Improvement in vision was seen within 24 hours, and power began to recover on day 6. MRI orbits showed optic nerve enhancement bilaterally. On the MRI scan of the spine extensive T2 hyperintense abnormalities were reported centrally in the cord between C1 and T9. CSF was positive for IgG oligoclonal bands and Aquaporin 4 antibodies, a highly specific serological marker of NMO. CSF lymphocyte count was also raised at 90. A previous case report from the UK describes a severe relapsing symptom course in a child with seropositive disease. Conclusion/Learning Points This rare presentation encompasses some less classical aspects of NMO presentation. Previous case reports have mentioned intractable vomiting and pruritis as the initial symptoms with a diagnosis of NMO not being made until neurological signs manifested.