一家系2例遗传性压迫易感性神经病报道

The clinical characteristics, electroneurophysiology and pathology of hereditary neuropathy with liability to pressure palsies: two cases of one pedigree

目的 报道一家系 2例遗传性压迫易感性神经病(HNPP) ,以提高对本病的认识及诊断水平。方法 2例均行详细肌电图、运动及感觉神经传导速度、运动神经远端潜伏期测定。1例行腓肠神经活检 ,标本分别在光镜或电镜下观察。结果 例 1临床表现为反复的压迫或牵拉后肢体无力和麻木。例 2为例 1父亲 ,临床无发病 ,查体有周围神经病表现。 2例电生理检查示广泛性神经传导速度减慢 ,特别是周围神经嵌压部位运动传导速度减慢更明显 ,运动神经远端潜伏期延长 ,包括临床未受累的神经。腓肠神经活检电镜见大多数有髓纤维髓鞘增厚 ,有的髓鞘向轴索内突出 ,轴索未见异常。无葱皮样改变。无髓纤维未见显变。结论 神经电生理检查是诊断HNPP重要的筛选手段 。

Objective To elucidate the clinical, electrophysiological, neuropathological features of two cases of hereditary neuropathy with liability to pressure palsies (HNPP) in one pedigree, and to review the literature of HNPP, so as to promote the understanding and diagnostic acuity of the disease. Methods Detailed electromyogram, motor and sensory conduction velocity, and distal motor latency were measured for clinically affected and unaffected nerves in the two patients. Sural nerve biopsy was performed for case one and the specimen was observed under light microscope and elcctronmicroscope. The cases reported in China up to the present were collected. Results Case one was an 18 year old male with a 9 year history of recurrent weakness and numbness of limbs precipitated by compression or stretch. Case two was his father. Although he had not experienced clinical episode of limb weakness and numbness, physiological examination revealed signs of peripheral neuropathy. Eletrophysiological study demonstrated diffuse peripheral nerve damage with decreased nerve conduction velocity, delayed distal motor latency, especially a decrease in motor conduction velocity at common entrapment sites, including clinical unaffected nerves. Sural nerve biopsy showed that myelin sheath of most myelinated fibers with normal axons was thickened. Some thickened myelin sheath was seen to invaginate into the axon. No onion bulb was found and unmyelinated fibers were relatively normal. Only 9 cases of HNPP were reported in China, but no DNA analysis was performed for any of them. Conclusions HNPP is a rare disease with autosomal dominant inheritance. Nerve conduction study is an important diagnostic method for screening. Its definite diagnosis relies on the typical pathological findings in nerve biopsy specimen. Sural nerve biopsy could be avoided for diagnosis if the family history were positive and nerve conduction study should show diffuse peripheral nerve damage