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

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.