Autoimmune-associated hemophagocytic syndrome originating from autoimmune hepatitis with a successful response to therapy.

The patient was a 15-year-old girl with severe acute hepatitis. A liver biopsy showed the typical findings of autoimmune hepatitis (AIH). Subsequently, two lineages of cytopenia were found in the patient's peripheral blood. Hemophagocytosis by macrophages was observed in the bone marrow. Virus-, drug- and lymphoma-associated hemophagocytic syndrome (HPS) was ruled out. Therefore, the patient was diagnosed with autoimmune-associated HPS (AAHS). Following the administration of combination therapy with prednisolone and cyclosporine A, both the AAHS and AIH improved. This is the first report of AAHS originating from AIH. The patient was followed up for five years after treatment, and no disease recurrence was detected.