Small fiber neuropathy and related factors in patients with systemic lupus erythematosus; the results of cutaneous silent period and skin biopsy

Abstract Introduction Evaluating small nerve fibers in patients with systemic lupus erythematosus (SLE) using cutaneous silent period (CSP) and skin biopsy and assesssing the relationship between clinical signs, autoantibodies and neuropathic pain score. Objective - methods Fifty one SLE patients and 46 healthy volunteers were included in this study. Nerve conduction studies and CSP were performed both on upper and lower limbs in subjects. Skin biopsy was performed and the number of epidermal nerve density and IL-6 staining were evaluated. Results In SLE patients, CSP latencies were significantly prolonged both in lower and upper limbs and lower and upper extremity CSP durations were significantly shorter when compared to controls ( p < 0.001). The number of epidermal nerve was significantly lower in SLE patients when compared to healthy controls ( p < 0.001). Conclusion We detected marked small nerve fiber damage in both lower and upper limbs in SLE patients using CSP. Decreased epidermal nerve density also supports this finding.(AU)

Establishing mouse model of type 2 diabetes peripheral neuropathy and measuring its intra-epidermal nerve fiber density / 临床麻醉学杂志

Objective To establish mouse model of type 2 diabetes peripheral neuropathy and measure its intra-epidermal nerve fiber density (IENFD).Methods Male C57BL6 mouse were ran-domly divided into four groups:group HS (n =6):high-fat diet+single streptozotocin intraperitoneal injection (120 mg/kg);group H (n =6):high fat diet+buffer injection;group S (n =6):standard chow diet+single streptozotocin intraperitoneal injection (120 mg/kg);group C (n = 6 ):standard chow diet+buffer injection.The 24th week was the end point of the experiment,and random glucose, homeostasis model assessment of insulin resistance (HOMA-IR),mechanical threshold,and IENFD were measured.Results Group HS had significantly higher random glucose and HOMA-IR than other groups (P <0.01),had significantly lower mechanical threshold than other groups (P <0.05), had significantly lower IENFD than groups S and C at 24th week (P <0.05 );group H had signifi-cantly higher random glucose and HOMA-IR than group C at 24th week (P <0.01),had no signifi-cant difference in mechanical threshold compared with group S and group C,and had no significant difference in IENFD compared with group HS.Conclusion A mouse model of type 2 diabetes periph-eral neuropathy was successfully established,and the IENFD was found to be decreased significantly.

Comparison of Somatic and Sudomotor Nerve Fibers in Type 2 Diabetes Mellitus

BACKGROUND AND PURPOSE: The objective of this study was to find a sensitive method for the early detection of diabetic polyneuropathy (DPN) and determine the relationship between the functions of somatic and autonomic small nerve fibers in DPN. METHODS: Patients with type 2 diabetes mellitus and DPN based on clinical symptoms, signs, intraepidermal nerve fiber density (IENFD), and findings in the quantitative sudomotor axon reflex test (QSART) were enrolled retrospectively. Neurological examinations and nerve conduction studies were performed on all patients. Heart-rate variability during deep breathing (DB ratio) and the Valsalva maneuver (Valsalva ratio) were used to quantify the cardiovagal function. Patients were divided into two groups: 1) normal nerve conduction, defined as small-fiber neuropathy (SFN) and 2) abnormal nerve conduction, defined as mixed-fiber neuropathy. RESULTS: In total, 82 patients were enrolled (age: 60.7±10.7 years, mean±SD). A decreased IENFD was the most frequent abnormality across all of the patients, followed by abnormalities of the QSART and cardiovagal function. A decreased IENFD was more sensitive than the QSART, DB ratio, and Valsalva ratio for detecting diabetic SFN. The DB ratio was significantly correlated with the duration of diabetes mellitus and clinical symptoms and signs. There was no correlation between the IENFD and the findings of the QSART for the distal leg. CONCLUSIONS: Measuring the IENFD was a more sensitive method than the QSART for the early detection of DPN. The degree of involvement of the somatic small nerve fibers and sudomotor nerve fibers was independent in DPN.