Increase of S-100 immunoreactivity in the urinary bladder from patients with multiple sclerosis, an indication of peripheral neuronal lesion.

The Schwann cells in urinary bladder biopsies from multiple sclerosis patients and controls were examined by immunocytochemistry with an antiserum to S-100. S-100 immunoreactivity was found to be markedly increased in these tissues as compared with the controls, indicating a Schwann cell hyperplasia in the urinary bladder in multiple sclerosis. This finding suggests that local neuronal damage exists in the urinary bladder of patients with multiple sclerosis. Therefore, the concept of multiple sclerosis as a disease wholly of the central nervous system should be reexamined.