[Analysis of clinical characteristic of children with progressive familial intrahepatic cholestasis type 3]

Abstract

Objective: To analyze the clinical manifestations, pathology, and gene variant characteristics in children with progressive familial intrahepatic cholestasis type 3 (PFIC3). Methods: This retrospective study assessed the clinical manifestations, pathological features, gene variants, and prognosis data of 11 children with PFIC3 hospitalized in the Department of Hepatology, Fifth Medical Center, PLA General Hospital, from January 2015 to December 2022. Panel or whole exome sequencing was performed on the probands, followed by Sanger sequencing for verification within the family. Detected pathogenic variants were compared with known disease databases. Additionally, the new variants were predicted the deleteriousness and protein structure using relevant software to evaluate their pathogenicity. Results: Among the 11 PFIC3 children, 8 were boys and 3 were girls. The age of onset was 3.1 (0.2, 15.6) years. The main complaint of onset was different in the 11 patients;5 of them were abnormal liver function, 3 of them were liver and spleen enlargement, 2 of them were abdominal distension, and 1 of them was jaundice. Alanine aminotransferase, asparate aminotransferase and γ-glutamyltransferase increased in all the patients, which were(113±40), (150±44) and (270±156) U/L respectively. Moreover, direct bilirubin increased in 9 patients, and cholestasis was showed in 8 patients. All patients showed liver fibrosis on imaging, and 8 patients had cirrhosis. The pathological features of 8 cases by liver biopsy were as follows: 8 cases of fibrosis in the portal area, 7 cases of small bile duct hyperplasia, 4 cases of positive copper staining, and 5 cases of cirrhosis. A total of 17 ABCB4 gene variants were detected, including 9 new variants: c.589C>T(p.Q197X), c.1230+1G>A(Splicing), c.2914G>A(P.D972N), c.1058G>A(p.C353Y), c.956G>T(p.G319V), c.473T>A(p.L158Q), c.164T>C(p.L55S), c.2493G>C(p.R831S), and c.1150G>C(p.G384R). All 11 patients were treated with ursodeoxycholic acid and followed up for 5.1(0.6, 7.4) years. Among them, 4 cases of cirrhosis progressed continuously, 3 cases had liver transplantations, and the remaining 4 cases were stable after medical treatment. Conclusions: Children with PFIC3 have early onset, diverse clinical manifestations, rapid progression of fibrotic and cholestasis, as well as poor prognosis. Genetic testing helps to confirm the diagnosis.