摘要
目的 报道 2例以胃肠道功能异常和肌无力为主要表现的线粒体病 ,探讨本病的诊断规律。方法 2例男性患者分别为 1 3岁和 6岁 ,在 6岁和 4岁 5个月时起反复出现胃肠道症状和持续性肌无力 ,无眼外肌瘫痪和中枢神经系统损害的表现 ,头颅CT和MRI检查无异常 ,对 2例患者进行肌肉活检和线粒体基因检查。结果 肌肉活检证实 2例患者的骨骼肌存在大量典型的不整红边纤维和琥珀酸脱氢酶深染的肌纤维 ,肌纤维内糖原和脂肪滴增多。电镜检查显示肌纤维内出现大量巨大线粒体 ,部分线粒体内出现环状排列的嵴或类结晶包涵体 ,肌纤维内糖原和脂肪滴增多。基因检查示 2例患者分别存在线粒体基因 32 4 3点突变和 32 71点突变。结论 胃肠道功能异常和肌无力可以作为主要临床症状组合出现在线粒体病中 ,由于 2例患者的临床表现不同于以前报道的线粒体脑肌病 ,应诊断为线粒体胃肠肌病 ,可能属于线粒体病一个新的临床病理亚型。
Objective To report two cases of mitochondrial disease presenting with marked gastrointestinal symptoms and mild myopathy without involvement of central nerve system as to investigating the diagnostic rules of the disease Methods Case 1 is a 13 year old boy who had suffered from recurrent vomiting with mild diarrhea and fatigue for 7 years Physical examination showed mild weakness of both legs without ophthalmoplegia and cognitive defects Radiological examination revealed gastroptosis with excessive peristalsis of small intestine Case 2 is of a 6 year old boy who showed repeatedly the recurrent vomiting, intestinal pseudo obstruction and persistent muscle weakness over 1 year and 7 months There were no ophthalmoplegia. Barium clysis showed marked dilatation of colon. Cranial MRI in case 1 and CT in case 2 were unremarkable Muscle biopsies were performed in both cases and specimens were studied using routine histological and histochemical staining as well as using ultrastructural examination mtDNA analysis were performed in both cases Results Histological and enzym histochemical staining showed RRF and SDH positive fibers in both cases. Electron microscopic studies revealed mitochondrial proliferation with paracystalline inclusions in the muscle fibers with mild accumulation of lipid and glycogen. Genetic study revealed point mutation in mtDNA 3243A→G in case 1 and mtDNA3271T→C in case 2 Conclusion Mitochondrial cytopathy might be diagnosed upon the myopathological and genetic findings Different from MNGIE, Leigh disease and MELAS, the main clinical features were gastrointestinal symptoms, mild muscle weakness and no involvement of central nerve system in our patients, thus the mitochondrial entero myopathy, a new clinicopathological type of mitochondrial disorders, might be considered Since the muscle weakness was usually overlooked in patients with diarrhea, the mitochondrial cytopathy occurring should be considered with more attention as to elucidating the causes of children who have chronic gastrointestinal symptoms
出处
《中华神经科杂志》
CAS
CSCD
北大核心
2003年第2期142-145,共4页
Chinese Journal of Neurology
基金
北京大学基因中心资助项目( 2 0 0 0A14 )
