1例2-甲基3-羟基丁酰辅酶A脱氢酶缺陷症患儿的临床诊治

Clinical diagnosis and treatment of 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency in one infant:a case report

目的:通过对1例2-甲基3-羟基丁酰辅酶A脱氢酶缺陷症患儿的临床表现及检查结果的分析,提高对此类疾病的认识,为该病的及时诊断和治疗提供依据。方法:采用回顾性方法对我院收治的这名患儿的临床症状和体征、实验室常规检查结果、血、尿串联质谱和气相质谱检查结果、X光胸片、彩超、头颅MR、脑电图以及诊疗情况进行回顾和分析。结果:患儿3岁,主要临床表现初期以腹泻、呕吐为主,后来出现嗜睡、意识障碍,气促、难以纠正的代谢性酸中毒等。头颅MRI显示双侧侧脑室轻度扩张,脑沟、脑裂稍增宽。脑电图检查结果为界线性幼儿期脑电图,额、中央区尖波数次发放。血串联质谱检查天冬氨酸等氨基酸升高,尿气相质谱2-甲基-3-羟基丁酸明显增高,但未发现甲基巴豆酰甘氨酸和2-甲基乙酰已酸的异常,基因检测结果为hadh2基因第4外显子p.R130C突变。结论:2-甲基3-羟基丁酰辅酶A脱氢酶缺陷症极为罕见,对有不明原因的难于纠正的代谢性酸中毒、高氨血症、或不明原因的精神萎靡、意识障碍等神经系统症状患儿应警惕该病,可送血或尿标本进行串联质谱、气相质谱及基因分析,以便早期诊断及治疗。

Objective：To The clinical manifestations and examination results of one infant with 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency（MHBDD）was reviewed to enhance the understanding,diagnosis and treatment of MHBD.Methods：The clinical manifestations and results of laboratory tests,tandem mass spectrometry of the blood sample,gas chromatography-mass spectrometry of the urine sample,chest X-ray,color Doppler examination,brain MRI and EEG as well as the treatment of this case were analyzed retrospectively.Results：This infant,aged 3 years old,mainly presented the symptoms of diarrhea and vomiting initially,and later lethargy,disturbance of consciousness,dyspnea and incorrigible metabolic acidosis.Brain MRI indicated mild ventriculomegaly and widening of sulci bilaterally.Borderline EEG was observed,with several sharp wave discharges in the frontal and central regions of the brain.Tandem mass spectrometry of the blood sample indicated increased levels of aspartic acid and other amino acids;gas chromatography of the urine sample indicated an obvious increase of 2-methyl-3-hydroxybutyric acid,but the levels of3-methylcrotonyl-glycine or 2-methyl-acetoacetic acid were basically normally.Gene detection revealed p.R130 C mutation in exon 4 of the hadh2 gene.Conclusion：As a rare disease,MHBDD may be suspected for infants presenting with incorrigible metabolic acidosis and hyperammonemia or neurological symptoms such as lethargy and disturbance of consciousness for unknown reasons.Examination techniques including tandem mass spectrometry,gas chromatography-mass spectrometry of the blood and urine samples and gene detections can be used for early diagnosis and treatment.