Hong Y-H, Kim M, Kim H-J, Sung J-J, Kim S H, Lee K-W
Department of Neurology, Clinical Research Institute, and Neuroscience Research Institute in Seoul National University Hospital, College of Medicine, Seoul National University, Korea.
Acta Neurol Scand. 2003 Nov;108(5):352-8. doi: 10.1034/j.1600-0404.2003.00132.x.
Although the diagnosis of hereditary neuropathy with liability to pressure palsies (HNPP) is important for correct prognostic evaluation and genetic counseling, the diagnosis is frequently missed or delayed. Our main aim on undertaking this study was to characterize the electrodiagnostic features of HNPP.
Clinical, electrophysiologic and molecular studies were performed on Korean HNPP patients with 17p11.2 deletion. The results of electrophysiologic studies were compared with those of Charcot-Marie-Tooth disease type 1 A (CMT1A) patients carrying 17p11.2 duplication.
Eight HNPP (50 motor, 39 sensory nerves) and six CMT1A (28 motor, 16 sensory nerves) patients were included. Sensory nerve conduction was slow in 97% of HNPP nerves. Motor nerve conduction at common entrapment sites was also abnormally slow in 87.5%, whereas at non-entrapment sites conduction slowing was infrequent. Distal motor latency (DML) was prolonged in 80% of HNPP nerves, and terminal latency index (TLI) was significantly lower in HNPP than in normal controls and in CMT1A patients (P < 0.01). In contrast to CMT1A, where severity of nerve conduction slowing was not different among nerve groups, HNPP sensory nerve conduction was more slowed in the median and ulnar nerves than in the sural nerve (P < 0.01), and DML was more prolonged in the median nerve than in the other motor nerves (P < 0.01). TLIs were significantly lower in HNPP than in the normal control and CMT1A patients for the median and ulnar nerves (P < 0.01), and were also significantly reduced for the peroneal nerve (P < 0.05) compared with those of the normal controls.
HNPP is characterized electrophysiologically by a generalized neuropathy, superimposed by focal entrapment neuropathies. The slowing of sensory conduction in nearly all nerves and the distal accentuation of motor conduction abnormalities are the main features of background polyneuropathy in HNPP. The distribution and severity of the background electrophysiologic abnormalities are closely related to the topography of common entrapment or compression sites, which suggests the possible pathogenetic role of subclinical pressure injury at these sites in the development of the distinct background polyneuropathy in HNPP.
尽管遗传性压力易感性周围神经病（HNPP）的诊断对于正确的预后评估和遗传咨询很重要，但该诊断经常被漏诊或延误。我们开展这项研究的主要目的是描述HNPP的电诊断特征。
对患有17p11.2缺失的韩国HNPP患者进行临床、电生理和分子研究。将电生理研究结果与携带17p11.2重复的1型遗传性运动感觉神经病（CMT1A）患者的结果进行比较。
纳入8例HNPP患者（50条运动神经，39条感觉神经）和6例CMT1A患者（28条运动神经，16条感觉神经）。97%的HNPP神经感觉神经传导速度减慢。在常见卡压部位，87.5%的运动神经传导也异常减慢，而在非卡压部位传导减慢不常见。80%的HNPP神经远端运动潜伏期（DML）延长，HNPP的终末潜伏期指数（TLI）显著低于正常对照组和CMT1A患者（P<0.01）。与CMT1A不同，CMT1A各神经组间神经传导减慢的严重程度无差异，而HNPP的正中神经和尺神经感觉神经传导比腓肠神经减慢更明显（P<0.01），正中神经的DML比其他运动神经延长更明显（P<0.01）。HNPP正中神经和尺神经的TLI显著低于正常对照组和CMT1A患者（P<0.01），与正常对照组相比，腓总神经的TLI也显著降低（P<0.05）。
HNPP的电生理特征为广泛性神经病，叠加局灶性卡压性神经病。几乎所有神经的感觉传导减慢以及运动传导异常的远端加重是HNPP背景性多发性神经病的主要特征。背景性电生理异常的分布和严重程度与常见卡压或压迫部位的解剖位置密切相关，这提示这些部位的亚临床压力损伤在HNPP独特的背景性多发性神经病发生中可能具有致病作用。
