Reports on the histologic aspects of the autonomic nerves in diabetics are infrequent. This investigation was carried out to study histologically and histochemically the autonomic nerve fibers of the urinary bladder wall in ten diabetic patients. Of the five subjects examined by biopsy, four showed damage of nerve fibers; absence of cholinesterase activity was the only finding in the fifth patient who had chemical diabetes.
In four autopsies we found alterations in all the cases. The lesions appeared as beaded or spindle-shaped fibers or small vacuolated or uniformly thickened fibers. The most severe cases exhibited fragmentation of the fibers.
Histochemical analysis demonstrated absence of cholinesterase activity in the muscle, in all cases, and absence or decrease of such activity in the nerves in all but one case. Similar studies performed on eight nondiabetic subjects revealed no anatomic or histochemical lesions.
The findings lead to the hypothesis that diabetic neuropathy injures the biochemical phase ofthe myelin sheath in the first stage and the nerve fibers later. No previous reports on the subject here studied could be found in the literature.