Concurrence of Alzheimer's disease, Parkinson's disease, diffuse Lewy body disease, and amyotrophic lateral sclerosis.

A 71-year-old man developed signs of progressive dementia, followed by extrapyramidal and motor neuron disease symptoms, which led to death in 6 years. Neuropathological examination revealed neuritic plaques, neurofibrillary tangles, and Lewy bodies in the substantia nigra and neocortex. Atrophy and gliosis with intraneuronal ubiquitin inclusions were present in the anterior horns of the spinal cord. Overlapping of Alzheimer's disease, Parkinson's disease, diffuse Lewy body disease and amyotrophic lateral sclerosis is rare and can increase our understanding of the process of neurodegeneration.