Autoimmune myelofibrosis. A steroid-responsive cause of bone marrow fibrosis associated with systemic lupus erythematosus.

Autoimmune myelofibrosis is an uncommon disorder in which patients present with anemia and thrombocytopenia in conjunction with limited clinical manifestations of autoimmune disease or an exacerbation of previously established SLE. The presence of leukoerythroblastosis in a patient with SLE may suggest the presence of myelofibrosis. Conversely, the absence of splenomegaly in a patient with presumed idiopathic myelofibrosis may suggest an autoimmune etiology. Patients with autoimmune myelofibrosis universally have a positive ANA test and frequently have either elevated anti-DNA titers or a positive LE cell preparation. Because physical manifestations of autoimmune disease may not be evident at presentation, all patients found to have myelofibrosis should have an ANA test. Peripheral blood cytopenias in autoimmune myelofibrosis frequently respond to glucocorticoids but regression of bone marrow fibrosis may be incomplete. Hematologic response to treatment parallels that of the associated autoimmune disease.