Alagille Syndrome RegistryPediatric Evaluation and Registry for Liver Cholestasis in Canada

The purpose of this study is to create a national, multi-centre registry for children with Alagille syndrome (ALGS) and Genetic Intrahepatic Cholestasis (GIC) that follows participants long-term, ensuring standardized, high-quality data capture across all participating pediatric hepatology centres.

Inclusion criteria:

• Pediatric participants (<18 years old) with genetically confirmed or clinically diagnosed ALGS or any of the various subtypes of GIC, each associated with a distinct genetic mutation: A. PFIC Type 1 (FIC1 Deficiency) - Mutation in ATP8B1 gene. B. PFIC Type 2 (BSEP Deficiency) - Mutation in ABCB11 gene. C. PFIC Type 3 (MDR3 Deficiency) - Mutation in ABCB4 gene. D. PFIC Type 4 (TJP2 Deficiency) - Mutation in TJP2 gene. E. PFIC Type 5 (FXR Deficiency) - Mutation in NR1H4 gene. F. PFIC Type 6 (MYO5B-Associated) - Mutation in MYO5B gene. G. Progressive cholestasis of northwestern Quebec (PCNQ)-Mutation in UTP4 gene.

• Enrollment within Canadian pediatric liver centers participating in the registry.
• Written informed consent obtained from participant if they have the capacity, or parents/guardians, and assent from participants as appropriate.

Exclusion criteria:

• Inability to comply with follow-up requirements (lost to follow-up). Participants will be recruited from our hepatology clinics retrospectively (diagnosed on or after January 1, 2022) and prospectively (newly diagnosed). Written consent/assent will be obtained from all participants prior to data collection from the participants' medical chart.