Cappellari A, Airaghi L, Capra R, Ciammola A, Branchi A, Levi Minzi G, Bresolin N
Service of Clinical Neurophysiology, Dino Ferrari Centre, Department of Neurological Sciences, IRCCS Ospedale Maggiore di Milano and University of Milan, Milan, Italy.
Electromyogr Clin Neurophysiol. 2005 Jun;45(4):241-4.
Increased prevalence of impaired glucose tolerance (IGT) has been recently detected in patients with painful sensory neuropathy. To determine whether nerve abnormalities are present in IGT we investigated IGT subjects without clinical neuropathy. Nerve conduction studies (NCS) were performed in 12 subjects with IGT without symptoms and signs of neuropathy. The results were compared with those obtained from 12 patients with type 2 diabetes (DM) without clinical neuropathy and 12 healthy controls. Sensory NCS of the sural nerve were performed on different segments, the distal-leg (10 cm proximal to the lateral malleolus) and the proximal-leg segment (10 cm more proximal). The distal conduction velocity of the sural nerve was increased in IGT subjects, compared both to healthy controls and DM patients. No difference was found among the groups with respect to the sensory conduction velocity of the sural nerve fibers in the proximal-leg segment. A reduction of both distal and proximal amplitudes of the sural nerve action potentials was detected in DM patients compared with IGT subjects and controls. The abnormal conduction velocity in the distal segment of the sural nerve, observed in IGT subjects without clinical neuropathy, suggests that the myelin dysfunction of the distal sensory fibers represents the earliest detectable nerve response to the hyperglycemia. The reduced amplitude of the sural nerve action potential in asymptomatic patients with DM arises from the axonal degeneration and represents a more advanced stage of nerve disease.
近期在痛性感觉神经病变患者中检测到糖耐量受损（IGT）的患病率增加。为了确定IGT患者是否存在神经异常，我们对无临床神经病变的IGT受试者进行了研究。对12例无神经病变症状和体征的IGT受试者进行了神经传导研究（NCS）。将结果与12例无临床神经病变的2型糖尿病（DM）患者和12例健康对照者的结果进行比较。对腓肠神经在不同节段进行感觉NCS，即小腿远端（外踝近端10 cm）和小腿近端节段（再近端10 cm）。与健康对照者和DM患者相比，IGT受试者腓肠神经的远端传导速度增加。在小腿近端节段，各研究组之间腓肠神经纤维的感觉传导速度没有差异。与IGT受试者和对照者相比，DM患者腓肠神经动作电位的远端和近端波幅均降低。在无临床神经病变的IGT受试者中观察到的腓肠神经远端节段异常传导速度，提示远端感觉纤维的髓鞘功能障碍是对高血糖最早可检测到的神经反应。无症状DM患者腓肠神经动作电位波幅降低是由轴突变性引起的，代表神经病变的更晚期阶段。
