Systemic Lupus Erythematosus with Autoimmune Myelofibrosis, Immune Thrombocytopenic Purpura, and Widespread Lytic Bone Lesions Successfully Treated with Rituximab and Romiplostim: a Case-Based Review

Autoimmune myelofibrosis (AIMF) is a rare complication of systemic lupus erythematosus (SLE) characterized by deposition of collagen and reticulin fibers in the bone marrow mediated by an aberrant production of fibrogenic cytokines and autoantibodies. Cytopenias in SLE/AIMF result from simultaneous underproduction secondary to myelofibrosis and peripheral destruction of blood cells. A 43-year-old woman was admitted for symptomatic pancytopenia associated with chest pain, dizziness, and headaches. Initial studies showed pancytopenia with diffuse osteolytic lesions particularly prominent on the skull, suggesting a possible malignancy. Additional diagnostic workup revealed a new diagnosis of SLE (+ANA, +dsDNA, low C3/C4), myelofibrosis secondary to SLE ( JAK2 and CALR negative; bone marrow biopsy showing diffuse grade 4 reticulin and collagen fibrosis), and concurrent immune thrombocytopenic purpura (ITP). She experienced severe thrombocytopenia with minimal response to frequent platelet transfusions and multiple first-line therapies including high-dose prednisone, hydroxychloroquine, and intravenous immunoglobulin. Ultimately, she was treated with rituximab and romiplostim that resulted in stabilization of her platelet count and resolution of osteolytic lesions at 1-year follow-up. The concomitant occurrence of AIMF and ITP in SLE is particularly rare and carries considerable prognostic significance. This presentation of SLE was further complicated by osteolytic lesions in the absence of malignancy, resistance to first-line therapies, and high mortality risk with severe unremitting thrombocytopenia dependent on platelet transfusions. As this constellation of symptoms and pathology posed significant challenges in diagnosis and management, representing the first documented case, we review the literature and discuss our approach and successful treatment.