晚发型系统性肉碱缺乏症2例临床、电生理及病理特点

A clinical,electrophysiological and pathological study in 2 cases of late-onset systemic carnitine deficiency

目的:通过报道2例少见的晚发型系统性肉毒碱缺乏的病例,分析其临床、电生理和病理特点,以期提高人们对这种少见但可治疾病的临床认识及诊断能力。方法:采用酶学方法进行血清肉碱测定,对双侧胫前肌、股四头肌、三角肌进行肌电图检查,对双腓总神经、双胫神经进行神经传导速度测定。对三角肌进行活检检查。结果:2例患者均为中年发病,进行性四肢近端无力,发作性肌肉易疲劳,血清肌酶增高,电生理为肌源性损害合并神经源性损害,肌肉病理显示肌纤维内大量的脂质颗粒沉积、Ⅰ型纤维受累为主,血清肉碱含量明显降低。诊断为脂质沉积性肌病,分型为系统性肉碱缺乏症(晚发型)。结论:病理检查是诊断与鉴别脂质沉积性肌病的重要方法之一,而血生化检测对其病因诊断的确定及选择适当的治疗则具有重要的临床意义。

AIM： To improve the clinical recognition and diagnosis of a rare but curable disease, late-onset systemic carnitine deficiency （SCD）, by reporting the clinical, electrophysiological and pathological features of two rare cases. METHODS： The clinical data of the two patients were collected, including serum carnitine measurement, electromyography of bilateral tibialis anterior muscle, quadriceps femoris and deltoid muscle, detection of nerve conduction velocity of bilateral common peroneal nerve, as well as muscle biopsy of deltoid muscle. RESULTS： Beginning in their forties, two patients developed progressive weakness of proximal extremities, episodic muscle fatigue and increased serum creatine kinase. The electrophysiological examination showed myogenic changes companied by neurogenic damages. The pathology of muscle biopsy demonstrated that a large amount of lipid storaged in muscle fibers especially in type I fibers. The serum carnitine level was decreased significantly, Their were diagnosed as lipid storage myopathy, which were classified as SCD （late-onset）. CONCLUSION： Pathological analysis is one of the important methods in the diagnosis and differentiation of lipid storage myopathy. The biochemical analysis of serum has great clinical significance in determining pathogenesis and selecting the optimal therapy.