Evaluation of Dermal Myelinated Fibers in Diabetic Polyneuropathy (IN1-1.002)

Abstract

Objective: We hypothesize that patients with diabetic polyneuropathy (DPN) will have evidence of demyelination in dermal myelinated fibers compared to healthy controls. Background Glabrous skin is enriched with myelinated fibers due to vertically oriented intrapapillary myelinated fiber endings (IME) to mechanoreceptors, the most common being Meissner corpuscles (MC). Therefore, biopsy of glabrous skin affords a minimally invasive method to investigate myelinated nerves. Design/Methods: Eight diabetic patients (3 with type 1, 5 with type 2) and six healthy age matched controls with mean age 55 vs. 51 were evaluated with clinical examination, the Michigan Diabetic Neuropathy Score (MDNS), nerve conduction studies (NCS), autonomic testing, and the Michigan Neuropathy Screening Instrument (MNSI). Immunohistochemistry was performed on 2 and 3 mm skin punches from the lateral index finger and distal leg, respectively. Results were analyzed with Kruskal Wallis or Wilcoxan Rank Sum test. Results: Peroneal motor conduction velocity, amplitude, composite autonomic severity score, MDNS and MNSI were significantly different in diabetic patients (p=0.04 to Conclusions: In conclusion, abnormalities in dermal myelinated fibers and mechanoreceptors are observed in DPN patients compared to controls. Further studies of dermal myelinated fibers may be helpful in elucidating the mechanism of demyelination in DPN. Supported by: NINDS K23 NS056009 to A.C. P., NINDS R01 R01NS066927-01 to J.L., Vanderbilt Diabetic Research Training Center, and Vanderbilt CTSA grant 1 UL1 RR024975. Disclosure: Dr. Myers has nothing to disclose. Dr. Li has nothing to disclose. Dr. Artibee has nothing to disclose. Dr. Peltier has nothing to disclose.