Neuropathological examination of the alterations of the intrinsic innervation in multiple sclerosis cystopathy.

Morphometric analysis of the innervation pattern of the stromal layer of the urinary bladder was done on biopsies from 88 patients with definite multiple sclerosis (MS). The biopsies were stained for acetylcholinesterase and for S100 protein, and a semiquantitative score was assigned. Nearly 30% of the samples showed increased immunoreactivity for S100, indicating Schwann cell hyperplasia. In 16% a decreased S100 immunoreactivity was found, the significance of which is unclear. More than 90% had normal acetylcholinesterase activity. No correlation could be demonstrated for age, sex, severity and duration of the disease, the presence of cystitis and type of detrusor dysfunction. The finding of altered S100 immunoreactivity in MS bladders could indicate that MS also affects the peripheral nervous system and is not limited to the central nervous system as classically described. This finding warrants further investigations.