关节挛缩、肾功能不全和胆汁淤积综合征一家系临床特点及VPS33B基因突变分析

Clinical features and VPS33B mutations in a family affected by arthrogryposis, renal dysfunction, and cholestasis syndrome

摘要:

关节挛缩、肾功能不全和胆汁淤积综合征 （ARC综合征）是VPS33B或VIPAS39基因突变导致的一种常染色体隐性遗传病。本文探讨1例ARC综合征患儿的临床特征及VPS33B基因突变特点。患儿，女，47 d，皮肤巩膜黄染45 d、肝功能异常39 d。曾在多家医院诊治，诊断不明，疗效欠佳。体查发现皮肤巩膜黄染，全身皮肤干燥，四肢及躯干部片状脱屑，心肺未见异常，肝右肋下2.0 cm可触及，髋关节和膝关节屈曲、伸展受限，四肢肌张力低。血清转氨酶、胆汁酸、胆红素 （以结合胆红素为主）等均升高，γ-谷氨酰转肽酶大致正常；尿常规发现尿糖及尿红细胞、白细胞均升高。遗传学分析证实患儿为VPS33B基因c.1594C > T （p.R532X）突变的纯合子，确诊为ARC综合征。予以对症支持治疗，病情无好转，3个月29天时死亡。

Abstract:

Arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome is an autosomal recessive disorder caused by mutations in the VPS33B or VIPAS39 gene. The aim of this study was to investigate the clinical features and VPS33B gene mutations of an infant with ARC syndrome. A 47-day-old female infant was referred to the hospital with the complaint of jaundiced skin and sclera for 45 days and abnormal liver function for 39 days. The patient had been managed in different hospitals, but the therapeutic effects were unsatisfactory due to undetermined diagnosis. Physical examination showed jaundice of the skin and sclera. Systemic skin was dry with desquamation in the limbs and trunk. There were no positive signs on cardiopulmonary examination. The liver was palpable 2.0 cm under the right subcostal margin. The hips and knees were flexed, and the extension was limited, with low muscular tone in the four limbs. Biochemical analysis demonstrated raised serum total bile acids, bilirubin (predominantly conjugated bilirubin) and transaminases, but the γ-glutamyl transpeptidase level was normal. Routine urine test revealed increased glucose as well as red and white blood cells. On genetic analysis, the infant was proved to be homologous for a VPS33B mutation c.1594C > T (p.R532X). She was definitely diagnosed to have ARC syndrome. Symptomatic and supportive therapy was given, but no improvement was observed, and the infant finally died at 3 months and 29 days of life.