Objective:To investigate the pathological features of blood stasis syndrome (BSS) in non-diabetic peripheral neuropathy.Methods:Clinical data of 31 patients with non-diabetic peripheral neuropathy who had undergone nerve biopsy during December 2004 and December 2010 in Xuanwu Hospital Capital Medical University were retrospectively analyzed.According to Chinese medicine (CM) syndrome differentiation and signs,26 patients were blood stasis type and 5 patients were non-blood stasis type.Clinical and pathological data were compared in detail.Results:Clinically,although both groups shared similar symptoms of limb numbness,weakness and sensory disturbances,the prevalence of neuralgia was much grievous in BSS group(73.1％,26/31) compared with the non-BSS group (0％,0/5).As for signs,dermal nutrients disturbance (84.6％,22/26),dark or purple tongue (100.0％,26/26),and sublingual varices (80.7％,21/26) were more common in the BSS group than the non-BSS group (0％,60％,20％,respectively).The prevalence of qi deficiency cases (19/26)in the BSS group was significantly higher compared with the non-BSS group (1/5).The unique histological manifestations of BSS were axonal degeneration (16/26 vs 2/5 in non-BSS group),which was the hallmark of ischemia.Cases with BSS had prominent microangiopathy (61.5％,16/26),manifested as epineurium vasculitis (inflammatory cell infiltrated to the vessel wall,obliteration and recanalization,vascular proliferation,extravascular hemosiderin deposition),angiotelectasis,proliferation and hyaline degeneration of endoneurium capillary.In the BSS group,impaired blood-nerve barrier was indicated by sub-perineurial edema (46.2％,11/26)and endoneurial edema (15.4％,4/26).The Renaut body (15.4％,4/26) and amyloid deposition (3.8％,1/26)found in the BSS group were absent in the non-BSS group.Conclusions:BBS was common in non-diabetic peripheral neuropathies.The nerves exhibited ischemic alteration of primary axon degeneration and secondary demyelination.The interstitial tissue revealed microcirculation impairment,blood-nerve barrier disturbance,amyloid deposition and proliferation changes.The high prevalence of qi deficiency also highlights the therapy of promotion of blood circulation and removal of blood stasis.