Clinical features and genetic diagnosis of neonatal carnitine-acylcarnitine translocase deficiency
LU Wei, LUO Fei-hong, WU Meng-yuan, et al
1. Department of Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai 201102, China; 2. Molecular Medical Center, Pediatric Research Institute, Children's Hospital of Fudan University, Shanghai 201102, China; 3. Department of Neonatology, Children's Hospital of Fudan University, Shanghai 201102, China)
Abstract: 【Abstract】 Objective To explore the clinical characteristics and genetic test results of carnitine-acylcarnitine translocase deficiency (CACTD). Methods From July 2016 to July 2018, totally 4 cases were diagnosed as CACTD in the molecular medical center of Children's Hospital of Fudan University, whose clinical characteristics, biochemistry changes and genetic test results were analyzed retrospectively, two of them were identical twins. Results The main clinical manifestations of the 4 cases were hypoglycemia after birth, feeding difficulty, hypotonia, irregular breath and arrhythmia. The biochemistry index showed hypoglycemia, hyperammonemia, hyperkalemia and elevation of creatine kinase. The tandem massspectrometry amino acids/acylcarnitines showed elevated levels of palmityl C16、hexadecenoyl C16:1、stearyl C18、(C16+oleyl C18:1)/ acetyl C2 and depressed level of free carnitine C0. The organic acids analysis by urine GC-MS showed elevated level of dicarboxylic acids. Four cases were performed gene detection, three of them were found with complex heterozygous variations of SLC25A20 gene (case 1 and case 2 were heterozygous mutations for c.199-10T>G and c.270delC, case 4 was heterozygous mutations for c.550G>T and c.199-10T>G) and one case was homozygous variation of SLC25A20 gene (case 3 was homozygous mutation for c.720_720insCCCACAGC). All the parents of the 4 cases were confirmed as carriers for the above gene variation by genetic verification. Four cases died within one week after birth. Conclusions The neonatal CACTD shows early onset, critical clinical manifestations and high mortality rate. It is advocated to carry out the mass spectrometry screening for neonatal inherited metabolic diseases. Blood and urine metabolic markers detection and gene analysis should be diagnosed clearly as early as possible for the suspicious neonates. Genetic counseling should be performed in families with certain genetic variants.
2019, Vol. 7 
