Summary

Japanese encephalitis (JE) is an epidemic encephalitis characterised by altered sensorium, convulsions, headache, brainstem signs with pyramidal and extrapyramidal features. Immune-mediated manifestation as acute transverse myelitis (ATM) has not been previously reported in JE. We describe a 40-year-old man who presented with an acute onset quadriparesis with urinary retention, which was preceded by fever and headache 3 weeks prior. He had elevated IgM titres against JE virus in serum and cerebrospinal fluid. MRI of cervico-thoracic spine demonstrated signal intensity alterations extending from C1 to D10 spinal segments. The patient was treated with intravenous methyl prednisolone for 5 days. He regained normal power at 6 months follow-up and repeat MRI study demonstrated complete resolution of the lesion. We conclude that in a case of JE, one should be vigilant for early diagnosis of possible complication as ATM, in which an early institution of immunomodulator therapy prevents adverse consequences.