cb1C型甲基丙二酸血症合并同型半胱氨酸血症的诊断学特征并文献复习  

Diagnostic features of cb1C-type mthylmalonic acidemia with homocysteinemia and literature review

作　　者：盛志强[1] 袁嫣然[1] 赵兵[1] 

机构地区：[1]济宁市第一人民医院儿童康复科,272013

出　　处：《中华诊断学电子杂志》2017年第4期281-284,共4页Chinese Journal of Diagnostics(Electronic Edition)

基　　金：济宁市科技局项目(济科字[2016]56号-55)

摘　　要：目的探讨甲基丙二酸血症的诊断学特征。方法回顾性分析2017年6月5日济宁市第一人民医院儿童康复科收治的1例cb1C型甲基丙二酸血症合并同型半胱氨酸血症患儿的临床资料并复习文献。结果患儿临床表现为全面发育迟缓、嗜睡、喂养困难、双眼凝视、反复皮疹。动态脑电图未见明显异常;颅脑磁共振示脑发育不良;神经心理发育评估示中度发育迟缓;同型半胱氨酸:117.60μmol/L;血串联质谱示蛋氨酸:3.40μmol/L,丙酰肉碱(C3):4.96μmol/L,丙酰肉碱/乙酰肉碱(C3/C2):1.01,丙酰肉碱/游离肉碱(C3/C0):0.29;尿有机酸示甲基丙二酸:303.19μmol/L,3-羟基丙酸:21.07μmol/L,甲基枸橼酸:5.43μmol/L;基因检测示MMACHC基因外显子2:c.217C>T(p.R73X)、外显子4:c.609G>A(p.W203X),为复合杂合变异,确诊为cb1C型甲基丙二酸血症合并同型半胱氨酸血症。结论甲基丙二酸血症临床表现无特异性,确诊需要行血串联质谱、尿气相色谱等代谢病筛查,具体分型则依赖于基因检测。Objective To explore the diagnostic features of mthylmalonic acidemia.Methods Theclinical data of a 4-months-old infantile combined with methylmalonic acidemia and homocysteinemia whowas diagnosed in the first People’s Hospital of Jining was retrospectively analyzed,the relevant literatureswere reviewed. Results The boy mainly presented with global developmental delay, drowsiness, feedingdifficulties, binocular gaze and repeated skin rash. The ambulatory electroencephalogram （ AEEG） wasnegative.The cerebral magnetic resonance imaging （ MRI ） showed cerebral hypoplasia. The neurologicaldevelopment was moderate mental retardation.The blood homocysteine was 117.60 μmol / L.The result of bloodtandem mass spectrometry was abnormal,the concentrations of methionine and carnitine were 3.40 μmol / Land 4.96 μmol / L,respectively. The ratios of C3 / C2 and C3 / C0 were elevated.Urine organic acid analysisshowed that the level of methylmalonic acid was elevated obviously which was 303.19 μmol / L,with elevated3 hydroxy propionic acid and methyl citrate,which were 21.07 μmol / L and 5.43 μmol / L,respectively.Thediagnosis was confirmed by molecular genetic study of the gene MMACHC,and there were two nonsensemutations （c.217C〉T,p.R73X and c.609G〉A,p.W203X）.The compound heterozygous mutations were fromhis parents respectively. He was diagnosed with cb1C-type methylmalonic acidemia and homocysteinemia.Conclusions The clinical features of methylmalonic acidemia are nonspecific.Diagnosis relies on analysis oforganic acids in plasma and / or urine by gas-liquid chromatography and mass spectrometry.Establishing thespecific subtype of methylmalonic acidemia requires molecular genetic testing.

关 键 词：甲基丙二酸血症 甲基丙二酸尿症 同型半胱氨酸血症 

分 类 号：R725.8[医药卫生—儿科]