摘要目的 探讨新生儿期碱酰基肉碱转位酶缺乏症(CACTD)的临床特征及肉碱溶质载体家族25成员20(SLC25A20)基因突变情况.方法 分析1例CACTD新生儿患者的临床特点,利用质谱技术检测患儿血酰基肉碱、尿有机酸代谢产物,采用Sanger直接测序法检测患儿及其父母SLC25A20基因的9个外显子.查阅中国知网、万方和PubMed数据库,比较分析国内外已报道CACTD新生儿患者的临床特征及CACTD基因突变位点.结果 本例男性患儿,生后数小时起病,出现青紫、恶性心律失常、心脏骤停、惊厥,低酮性低血糖、高血氨、高乳酸,头颅磁共振示代谢性脑病改变,血酰基肉碱游离肉碱水平低,长链酰基肉碱水平高,肉碱SLC25A20基因c.199?10T>G纯合突变,父母均为c.199?10T>G杂合突变.文献报道SLC25A20基因总共41种已知致病突变,c.199?10T>G突变常见于东亚地区,已经报道的12例c.199?10T>G突变的CACTD患者,均在新生儿早期发病,临床表现为心脏骤停、呼吸衰竭、惊厥、喂养困难等,病死率高.结论 新生儿早期出现心律失常、低血糖、高乳酸血症、惊厥等且病情急剧恶化,应高度警惕CACTD或其他脂肪酸氧化障碍的可能,及时行血酰基肉碱、尿气相色谱?质谱联用仪(GC?MS)、肉碱SLC25A20基因分析以明确诊断.

abstractsObjective To investigate the clinical features of carnitine?acylcarnitine translocase deficiency (CACTD) and mutation of the gene SLC25A20 (solute carrier family126 25 member 20) in newborn. Methods The clinical features of a newborn with CACTD were analyzed. Mass spectrometry was used to detect the blood acylcarnitine and urine organic acid metabolites in the child. Sanger direct sequencing was used to detect the 9 exons of SLC25A20 gene in the child and his parents. The CNKI, Wanfang and PubMed databases were retrieved. The clinical features and gene mutation loci in CACTD neonates reported in China and worldwide were compared. Results In this male patient,CACTD occurred hours after birth,presenting cyanosis,malignant arrhythmia,cardiac arrest,convulsion,hypoketotic hypoglycemia,hyperammonemia,and hyperlactosis. Head magnetic resonance showed signs of metabolic encephalopathy. His blood acylcarnitine tested a low level of free carnitine and a high level of long?chain acylcarnitine. Gene sequencing showed that the patient was a homozygous mutant,and both of his parents were heterozygous mutants,for carnitine SLC25A20 c. 199?10T>G. A total of 41 known pathogenic mutations of the SLC25A20 gene were reported in the literature,with the c. 199?10T>G mutation commonly seen in East Asia. So far 12 CACTD patients with c. 199?10T>G mutation have been reported,all identified early in neonates, clinically manifested by cardiac arrest, respiratory failure, convulsion, feeding difficulties,and with high mortality rate. Conclusion Early onset and rapid deterioration of arrhythmia, hypoglycemia,hyperlactosis,and convulsions in newborns should highly alert for a probable diagnosis of CACTD or other fatty acid oxidation disorders,and prompt for timely testing of blood acylcarnitine,urine gas chromatography?mass spectrometry(GC?MS),and carnitine SLC25A20 gene profiling in order to make a clear diagnosis.