Steroid-resistant autoimmune myelofibrosis in a patient with autoimmune hepatitis and Evans syndrome complicated with increased expression of TGF-β in the bone marrow: a case report.

We here report a 47-year-old female with autoimmune myelofibrosis (AIMF) associated with liver damage caused by autoimmune hepatitis and Evans syndrome. Bone marrow biopsy revealed hypocellular marrow with grade 2 reticulin fibrosis and increased levels of B lymphocytes (CD20), T lymphocytes (CD3, CD8), and plasma cells (CD138). Immunohistochemical analysis revealed increased expression of transforming growth factor-β (TGF-β) in infiltrating lymphocytes and macrophages in the bone marrow. She was initially treated with oral prednisolone (PSL) for 2 months, which had a limited effect. However, after treatment with rituximab, the patient's pancytopenia showed improvement, allowing us to rapidly reduce the PSL dosage. The present case suggests the possibility that increased expression of TGF-β in infiltrating lymphocytes and macrophages of bone marrow may contribute to the pathogenesis of AIMF. Prednisolone combined with rituximab may thus be an effective option for steroid-refractory cases.