线粒体脑肌病伴高乳酸血症和卒中样发作综合征误诊为病毒性脑炎回顾分析

A Retrospective Analysis on a Case Misdiagnosed as Viral Encephalitis: Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like Episodes

目的探讨线粒体脑肌病(mitochondrial encephalomyopathy,ME)的临床特点以及与病毒性脑炎的鉴别诊断要点。方法回顾性分析2例ME误诊病例资料。结果本文2例系母女,例1(母亲)因癫痫反复发作、谵语、少眠多次入院,病程长达17年,根据患者临床症状、血乳酸脱氢酶升高及影像学检查结果,诊断为症状性癫痫、病毒性脑炎,予对症治疗,症状反复发作,直至其女14年后发病、查血乳酸7.8 mmol/L方怀疑家族遗传性疾病,经基因检测、肌活检病理检查确诊为ME伴高乳酸血症和卒中样发作综合征(mitochondrial encephalomyopathy with lacticacidosis and stroke-like symptoms,MELAS);例2(女儿)以发作性意识不清入院,病初根据临床症状及相关检查考虑症状性癫痫、病毒性脑炎,予对症治疗,症状反复发作,病程中多次头颅影像学检查示病灶呈游走性,经查血乳酸6.6 mmol/L,追问家族史,获知其母亦有同样症状,怀疑家族遗传性疾病,经基因检测、肌活检病理检查确诊为MELAS。两例经相应治疗,病情稳定。结论 ME可多系统发病,每次发作表现常不一致,易误诊为病毒性脑炎,经查血乳酸水平、询问既往史和家族史可行早期筛查,确诊需基因检测、肌活检病理检查。

Objective To explore the causes of misdiagnosis of mitochondrial encephalomyopathy and the key points of differential diagnosis. Methods A retrospective analysis of the clinical data of 2 cases of misdiagnosis of ME was conducted. Results The 2 cases were mother and daughter. Case 1（ mother）,admitted for gibberish,sleepless,and epileptic episodes,paroxysmal unconsciousness for 17 years,and initially misdiagnosed as viral encephalitis according to headache,seizures,EEG slow wave increase,the head CT scanning and normal results of cerebrospinal fluid routine examination,was diagnosed as symptomatic epilepsy and encephalitis,and the patients received symptomatic treatment. Those symptoms relapsed,until the daughter＇s onset 14 years later. The lactic acid in blood was 7. 8 mmol / L,the disease was suspected as family heredity disease,and was diagnosed as mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes（ MELAS）;case 2（ daughter） suffered paroxysmal unconsciousness on admission and upon onset of the disease according to the clinical symptoms and related consideration of symptomatic epilepsy,encephalitis,symptomatic treatment,recurrent symptoms,in the course of multiple cranial imaging examination showed the lesion was wandering,and was found in blood lactic acid6. 6 mmol / L,and the family history showed that the mother also had the same symptoms,and was suspected as family heredity disease,but genetic testing,muscle biopsy and pathological examination confirmed the diagnosis of MELAS. In the two cases after the treatment,the patients were in stable condition. Conclusion ME can develop in multi-system disease and have different manifestations on each attack. It is easy to mistake the MELAS in the nervous system with viral encephalitis,and misdiagnosis,but differential diagnosis can be made based on the serum lactate levels,imaging,gene detection,pathological examination of muscle,previous history and family history. Serum lactate,previous history and family history should be considered in screening to prevent misdiagnosis.