An 11-year-old girl presented to us with history of sudden diminution of vision in the right eye. There was no associated history of altered sensorium, fever, headache, vomiting, rashes or head injury. She also had a history of feeling of decreased sensation in left arm 4 weeks ago, which recovered completely and spontaneously　within 2 weeks. There was decreased visual acuity in the right eye, with evidence of optic atrophy on fundoscopy. The Visual Evoked Potential (VEP) test revealed increased latency and decreased amplitude in the right eye.

Magnetic resonance imaging (MRI) of the brain showed multiple lesions involving white matter in bilateral periventricular, bilateral fronto-parietal subcortical and right temporal subcortical regions. On contrast enhanced cerebral MRI, few enhancing lesions were located in the corpus callosum, periventricular and bilateral frontal regions (Fig. 1). MRI spinal cord showed T2 hyperintense lesions in cord at C2, C4 and D12 vertebral levels. The cerebrospinal fluid analysis revealed normal cytology and biochemistry, with no oligoclonal band. Anti NMO antibodies were negative. According to Polman (2010 revised Mcdonald criteria) [1], diagnosis of multiple sclerosis (MS) was made and pulse corticosteroid therapy with methylprednisolone was started with strict monitoring of vital and laboratory parameters. The vision improved　within 24 hours　of initiation of therapy and the girl was discharged on oral steroids, after 3 days of intravenous therapy.

Fig.1 MRI Brain and MRI Spinal cord showing lesions consistent with multiple sclerosis.

Multiple sclerosis (MS) is a chronic demyelinating disorder of brain, spinal cord and optic nerves characterized by a relapsing-remitting course of neurologic events, separated in time and space, without encephalopathy, thus distinguishing it from acute disseminated encephalomyelitis [2]. Oligoclonal band in cerebrospinal fluid is considered to be a useful aid in diagnosis, but may be absent in up to 60% of confirmed pediatric cases. Its incidence is reported to be about 5.68/100000 per year, and the pediatric population accounts for about 2% to 5% of all MS cases [3]. Intravenous methyl prednisone is the preferred therapy in freshly diagnosed cases. Currently available first-line disease modifying therapies for adults, including interferon　â　and glatiramer acetate, have not been approved by the US FDA for the treatment of children with MS.

1. Polman CH,　Reingold SC, Banwell B, Clanet M, Cohen JA, Filippi M, et al. Diagnostic criteria for multiple sclerosis: 2010 revisions to the McDonald criteria. Ann Neurol. 2011;69:292-302.

2. Dale RC, Brilot F, Banwell B. Pediatric central nervous system inflammatory demyelination: acute disseminated encephalomyelitis, clinically isolated syndromes, neuromyelitis optica and multiple sclerosis. Curr Opin Neurol. 2009;22:233-40.