Sural nerve biopsy may predict future nerve dysfunction

Sural nerve pathology in peripheral neuropathy shows correlation with clinical findings and neurophysiological tests. The aim was to investigate progression of nerve dysfunction over time in relation to a baseline nerve biopsy. Baseline myelinated nerve fiber density (MNFD) was assessed in sural nerve biopsies from 10 men with type 2 diabetes, 10 with impaired and 10 with normal glucose tolerance. Nerve conduction and quantitative perception thresholds were estimated at baseline and follow-up (7-10 years later). Subjects with low MNFD (<= 4700 fibers/mm(2)) showed decline of peroneal amplitude (P < 0.02) and conduction velocity (P < 0.04), as well as median nerve sensory amplitude (P < 0.05) and motor conduction velocity (P < 0.04) from baseline to follow-up. In linear regression analyses, diabetes influenced decline of nerve conduction. MNFD correlated negatively with body mass index (r = -0.469; P < 0.02). Low MNFD may predict progression of neurophysiological dysfunction and links obesity to myelinated nerve fiber loss.