PIGG and Decreased liver function: Anti-F-actin and pIgG ELISAs showed the highest accuracy for predicting juvenile AIH/AISC and may complement existing diagnostic criteria.<h4>Impact and implications</h4>Autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (AISC) are rare paediatric liver diseases that can be difficult to distinguish from other hepatopathies.