Autoimmune hepatitis is a chronic inflammatory process of unknown ethology, characterised by high levels of transaminases and IgG antibodies, the presence of tissue autoantibodies, and a typical histological picture. In the population of children, the paediatric form of autoimmune hepatitis and autoimmune sclerosing cholangitis are collectively classified as juvenile autoimmune liver disease. The condition often coexists with other autoimmune disorders. This paper aims to present the clinical profile of a paediatric patient with full-blown autoimmune hepatitis and describe the available therapies. The patient, a 13-year-old boy, was referred to a specialised hospital because of increasing hypertransaminasaemia. The patient was hospitalised for the first time at a district hospital for abdominal pain, and during his stay, elevated transaminases were found with a tendency to increase in follow-up tests. The picture suggested an inflammatory process of the liver and biliary tract. Upper gastrointestinal endoscopy revealed lesions consistent with chronic gastritis and portal gastropathy. Treatment included thiazolidinedioic acid, vitamin K, ursodeoxycholic acid, rifaximin, ciprofloxacin, and proton pump inhibitors. Therapy is aimed at maintaining immunosuppression and inhibiting the inflammatory response that leads to cirrhosis, and most commonly uses steroids alongside proton pump inhibitors for added protection or, alternatively, mycophenolate mofetil, cyclosporine A, tacrolimus, and biologic therapy. Ursodeoxycholic acid also exhibits immunomodulatory properties and makes it possible to reduce steroid doses and thus decrease the likelihood of adverse effects of therapy.