新生儿甲基丙二酸血症的临床特征及基因诊断  

Clinical features and gene analysis of neonatal methylmalonic acidemia

作　　者：陈璐[1] 黄文娣 张娟利[1] 闫雯[1] 赵建刚[1] 蔡玉香 唐小晶 王志 赵玉娟[1] CHEN Lu;HUANG Wen-di;ZHANG Juan-li;YAN Wen;ZHAO Jian-gang;CAI Yu-xiang;TANG Xiao- jing;WANG Zhi;ZHAO Yu-juan(Neonatal Department, Xi＇an Children＇s Hospital of Shaanxi Province, Shaanxi, Xi＇an 710003, China)

机构地区：[1]陕西省西安市儿童医院新生儿科,陕西西安710003

出　　处：《发育医学电子杂志》2018年第1期40-44,共5页Journal of Developmental Medicine (Electronic Version)

摘　　要：目的探讨甲基丙二酸血症(methylmalonic acidemia,MMA)的临床特点及基因检测结果。方法 2014年6月至2017年6月,于陕西省西安市儿童医院新生儿科确诊的MMA患者共10例。采用回顾性研究的方法,分析患儿的临床资料、血尿常规、血液生化指标、影像学检查、血尿有机酸、血同型半胱氨酸及基因分析的结果。结果 10例患儿的主要临床特点为精神反应差、意识障碍、少哭少动甚至不哭不动、肌张力低下、原始反射减弱甚至消失、喂养困难、体重下降、黄疸、呼吸节律异常。生化指标提示高氨血症、代谢性酸中毒、白细胞减少、血小板减少、贫血。头颅影像学检查提示有脑损伤。尿有机酸分析示尿甲基丙二酸均明显增高,血C3/C2均升高,部分患儿血同型半胱氨酸升高。4例患儿进行基因检测,其中mut-型1例,cbl C型3例。4例出生即发病者均在生后不久死亡。6例存活患儿治疗后,临床症状均明显改善,但随访发现大部分患儿存在不同程度体格发育、运动及智力发育落后。结论新生儿MMA临床表现不典型,发病早,死亡率高,存活患儿多存在脑损伤。可疑患儿应及早行血、尿有机酸检测、血同型半胱氨酸测定及基因分析明确诊断,确诊后坚持长期合理治疗,以改善预后。Objective To explore the clinical characteristics and gene analysis of methylmalonic acidemia（MMA）.Methods From June 2014 to June 2017,totally 10 cases of infants were diagnosed as MMA who enrolled in Neonatal Department of Xi＇an Children＇s Hospital of Shaanxi Province.The clinical symptoms,routine test of blood and urine,blood biochemistry index,radiology imaging,organic acids analysis of blood and urine,results of blood homocysteine and gene analysis were analyzed by retrospective analysis method.Results The main clinical manifestations of the 10 cases were poor response,unconsciousness,loss of appetite and activity,hypotonia,weak primary reflex or even disappeared,feeding difficulty,weight loss,jaundice and irregular breath.The biochemistry index showed hyperammonemia,metabolic acidosis,leukopenia,thrombocytopenia and anemia.The radiology imaging showed brain injury.The urine organic acid analysis showed elevated level of methylmalonic and blood amino acids and acylcarnitine analysis showed elevated level of C3/C2.Several of them showed increased homocysteine in blood.Four cases received gene detection,one of them genotype was mut-and the other three were cbl C.Four cases of MMA were onset at birth and died shortly after birth.Six survival cases showed symptomatic improvement after treatment,but most of them had different degrees of retardation of physical development,movement and intellectual development according to the follow-up.ConclusionsThe clinical manifestations of the neonatal MMA are nonspecific.The neonatal MMA has an early onset and high mortality rate.The survival newborns may have brain injury.Suspicious cases should be given blood and urine amino acids test,blood homocysteine and gene analysis to make a definitive diagnosis as soon as possible.After diagnosis,long term regular and appropriate treatment should be taken so as to improve prognosis.

关 键 词：甲基丙二酸尿症 婴儿 新生 临床特点 生化 基因 

分 类 号：R440[医药卫生—诊断学] R722.1[医药卫生—临床医学]