A novel homozygous mutation in the USP53 gene as the cause of benign recurrent intrahepatic cholestasis in children: a case report

Background. Benign recurrent intrahepatic cholestasis (BRIC) is a rare cause of cholestasis with recurrent episodes of jaundice and pruritus without extrahepatic bile duct obstruction. A mutation in the USP53 gene is known to cause BRIC-like cholestasis with normal serum gamma-glutamyltransferase (GGT) levels. Case. We report a 16-year-old boy with recurrent episodes of cholestasis since 6 months of age with normal serum GGT levels. The liver biopsy showed ballooning degeneration of hepatocytes which is typical for BRIC, and intrahepatic and canalicular cholestasis with bilirubinostasis. We performed whole exome sequencing (WES) and identified a novel homozygous variant (NM_001371399.1:c.1558C > T) of the USP53 gene at exon 14 as the cause of BRIC. Conclusion. This is the first case of USP53 disease from Türkiye with a novel mutation in the USP53 gene. This novel identification of the mutation of c.1558C > T at exon 14 can provide elucidative data for those who work in the field of intrahepatic cholestasis. Our case suggests that USP53 disease must be kept in mind in patients with recurrent intrahepatic cholestasis with normal serum GGT levels.