Evaluation of small nerve fiber dysfunction in type 2 diabetes

Research output: Contribution to journalArticle

Abstract

Objectives: To assess potential correlations between intraepidermal nerve fiber densities (IENFD), graded with light microscopy, and clinical measures of peripheral neuropathy in elderly male subjects with normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and type 2 diabetes (T2DM), respectively. Materials and methods: IENFD was assessed in thin sections of skin biopsies from distal leg in 86 men (71-77 years); 24 NGT, 15 IGT, and 47 T2DM. Biopsies were immunohistochemically stained for protein gene product (PGP) 9.5, and intraepidermal nerve fibers (IENF) were quantified manually by light microscopy. IENFD was compared between groups with different glucose tolerance and related to neurophysiological tests, including nerve conduction study (NCS; sural and peroneal nerve), quantitative sensory testing (QST), and clinical examination (Total Neuropathy Score; Neuropathy Symptom Score and Neuropathy Disability Score). Results: Absent IENF was seen in subjects with T2DM (n = 10; 21%) and IGT (n = 1; 7%) but not in NGT. IENFD correlated weakly negatively with HbA1c (r = −.268, P =.013) and Total Neuropathy Score (r = −.219, P =.042). Positive correlations were found between IENFD and sural nerve amplitude (r =.371, P =.001) as well as conduction velocity of both the sural (r =.241, P =.029) and peroneal nerve (r =.258, P =.018). Proportions of abnormal sural nerve amplitude became significantly higher with decreasing IENFD. No correlation was found with QST. Inter-rater reliability of IENFD assessment was good (ICC = 0.887). Conclusions: Signs of neuropathy are becoming more prevalent with decreasing IENFD. IENFD can be meaningfully evaluated in thin histopathological sections using the presented technique to detect neuropathy.

Details

Authors
Organisations
External organisations
  • Skåne University Hospital
  • National University Hospital of Iceland
  • Mugla University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Neurology
  • Endocrinology and Diabetes

Keywords

  • diabetes mellitus type 2, diabetic neuropathies, inter-rater reliability, intraepidermal nerve fiber density, skin punch biopsy
Original languageEnglish
JournalActa Neurologica Scandinavica
Publication statusE-pub ahead of print - 2019 Sep 24
Publication categoryResearch
Peer-reviewedYes