September 24, 2020
This is an interesting common vascular finding in a sural nerve biopsy taken from an adult diabetic patient with paresthesias. This photomicrograph shows hyaline thickening of an endoneurial blood vessel wall (black arrow, right of center) due to reduplication of perivascular basement membrane material and plump endothelial cells with associated narrowing of the vascular lumina. These vascular changes are commonly seen in the setting of diabetic polyneuropathy and contribute to the myelinated axonal loss observed (i.e. axonopathic process) (toluidine blue stained thick section prepared from glutaraldehyde-fixed Epon resin-embedded tissue, 1000x oil immersion).