A study correlating nerve biopsy with clinical diagnosis and its impact on improving management in peripheral neuropathies

Background This study attempts to evaluate the utility of nerve biopsy in complementing or redirecting clinical diagnosis. Several factors determine the diagnostic utility of nerve biopsy, the most important being pre-biopsy diagnosis, with higher diagnostic yield reported in asymmetric and multi-focal neuropathies . Methods This retrospective study was conducted at a tertiary care hospital in South India, wherein, patients with a clinical and electrophysiological diagnosis of peripheral neuropathy who underwent nerve biopsy between Jan 2012- Dec 2016 were reviewed. Results A total of 112 nerve biopsies were performed at our Institute during the study period, of which, 84 had adequate information for review and inclusion in the study. In a majority (75) Sural nerve was biopsied, followed by combined superficial peroneal nerve and peroneus tertius muscle biopsy (5).Nerve biopsy diagnosis was concordant with and helped confirm the clinical diagnosis in 43/84 (51%) cases, which included vasculitic neuropathy (20), CIDP (16), leprous neuropathy (6). In10/84 (12%) patients, the nerve biopsy diagnosis was discordant with the clinical diagnosis and helped in redirecting management. This included vasculitic and diabetic neuropathy (2 each), Charcot Marie Tooth Disease (3), and leprous neuropathy (3). In 31/85 (37%) cases with no clinically evident etiological diagnosis, nerve biopsy proved useful in establishing diagnosis in 16/31 (51%) cases aiding patient management. This included Non-systemic vasculitic neuropathy (7), leprous neuropathy (3), diabetic neuropathy (2), and Giant axonal neuropathy (1). Conclusion Nerve biopsy remains a valuable tool in complementing or redirecting the clinical diagnosis, and improving the therapeutic outcomes in peripheral neuropathies. It should be done upfront in clinically idiopathic neuropathies, and early at follow up in treatment refractory neuropathies.