Spinal Muscular Atrophy: Autopsy Based Neuropathological Demonstration.

Spinal muscular atrophy (SMA) encompasses a group of disorders with loss of spinal motor neurons.The report describes the neuropathological findings including brain and spinal cord at autopsy in a five-and-half-month-old boy with suspected type 1 SMA. The anterior motor neurons, Clarke's column at all the levels of spinal cord showed neuronal loss and degeneration while neurons at all the deep grey nuclei were preserved apart from variable degree anoxic changes. Skeletal muscle biopsy revealed features of neurogenic atrophy consistent with SMA. A differential diagnosis like storage disorders was excluded using electron microscopy. No extra-neural manifestations were seen. Neuropathological features at autopsy have seldom been reported in the literature.