A 13-year-old Chinese boy with features of the Madras pattern of motor neuron disease (MMND) presented to us. The benign focal atrophy of the extremities, especially the upper, and associated hearing impairment were important clues to the clinical diagnosis. A recent pathological report suggests that an inflammatory aetiology needs to be considered for this special type of motor neuron disease. Therefore, treatment with intravenous immunoglobulin 400 mg/kg once daily was administered for 5 days, and improvement of symptoms was noted at 6 months of follow up.