TJP2 deficiency or PFIC4 is an autosomal recessive disorder caused by a mutation in the TJP2 gene, encoding the tight junction protein-2, which is involved in the organisation of epithelial and endothelial cell junctions.59 PFIC4 is characterised by early-onset cholestasis with severe progression.4
GGT is often normal or slightly elevated. PFIC4 can be complicated by hepatocellular carcinoma.4
Diagnosis
Diagnosis is confirmed by genetic sequencing of the TJP2 gene.4
4. Protocole national de diagnostic et de soins : Déficits de synthèse des acides biliaires primaires. Centre de Référence Coordonnateur de l’Atrésie des Voies Biliaires et des Cholestases Génétiques; 2019.
59. Sambrotta M, Strautnieks S, Papouli E, et al. Mutations in TJP2 cause progressive cholestatic liver disease. Nat Genet 2014;46:326-8.
