Besides adult patients, Kremer et al. also described significantly increased ATX levels in pediatric CCLD patients with pruritus (Alagille syndrome, extrahepatic biliary atresia, neonatal sclerosing cholangitis, PFIC) compared to children with BA synthesis defects, in which pruritus is typically not observed and tBA are low (26). Here, ENPP2 is linked to progressive familial intrahepatic cholestasis.