LAUSR

A twenty-nine-year-old male presented with subacute onset weakness of all four limbs associated with urinary retention over 10 days and encephalopathy for the last 4 days. He had an acute febrile illness 4 weeks prior to this episode. Brain and spine MRI revealed a longitudinally extensive transverse myelitis (LETM) from C2 to C7 (Fig. 1a) and multiple T2/FLAIR hyperintensities in the bilateral subcortical, juxtacortical and cortical regions (Fig. 1b). CSF revealed lymphocytic pleocytosis (WBCs 191, lymphocytes 98%), with raised proteins (169 mg/dl) and normal sugar level. CSF workup for infectious causes was negative. ANA, ANCA and serum NMO antibody were negative. He was found positive for MOG-IgG antibody on cell-based assay. He was treated with IV MPS followed by 5 cycles of plasma exchange. He showed significant clinical improvement in sensorium and motor weakness. He had no relapses in the subsequent 2-year follow-up on azathioprine.