HIV-related neuromuscular syndrome simulating motor neuron disease.

A young homosexual man presented with slowly progressive weakness and diffuse fasciculations. Muscle biopsy was compatible with clinical diagnosis of motor neuron disease. The patient died from opportunistic infections related to acquired immunodeficiency syndrome. Autopsy revealed evidence of myelopathy, patchy fiber loss from anterior nerve roots, marked demyelination within intramuscular twigs of peripheral nerves, and primary myopathic features superimposed on advanced neurogenic atrophy of the skeletal muscles.