While the pathogenesis of autoimmune myelofibrosis is not completely understood, in patients with systemic lupus erythematosus, it may be triggered by circulating immune complexes that induce megakaryocytes to release platelet-derived growth factor.
Hematologic disorders affect approximately 85% of patients with systemic lupus erythematosus (SLE). While most of these disorders comprise autoimmune hemolysis, leukopenia, thrombocytopenia, and anemia, myelofibrosis has also been described in these patients.
Autoimmune myelofibrosis is an uncommon disease, and its association with SLE is an even rarer condition. Writing in Leukemia Research Reports, physicians from Sapienza Università di Roma describe a case of SLE and myelofibrosis affecting a 43-year-old female patient.
The patient was admitted to the hospital with gallstones and gallbladder inflamation, and while undergoing treatment, she developed fever, anemia, inflammation of serous membranes, and thrombocytopenia. Laboratory tests also demonstrated increased levels of C-reactive protein and elevated erythrocyte sedimentation rate values.
After infections and neoplasms were ruled out via laboratory testing, a bone marrow biopsy was performed and showed hypercellular bone marrow containing erythroid and myeloid elements and megakaryocytes showing increased and hyperchromatic nuclei. Interstitial reticulin and collagen fibrosis were also observed. No spleen enlargement was found via ultrasound.
During hospitalization, the patient developed life-threatening renal dysfunction. Autoimmune tests were performed, confirming the presence of autoantibodies, and a diagnosis of SLE was given.
The patient was treated with methylprednisolone for 3 days and showed rapid improvement in clinical parameters and renal function. The immunosuppressive drug azathioprine was added to her therapy, leading to an increase in peripheral blood cell count to normal values. Within 3 months, the patient was able to reduce her dose of methylprednisolone.
After 1 year of treatment, a follow-up bone marrow biopsy showed complete remission of bone marrow fibrosis. After 2 years of maintenance therapy and follow-up, the patient still has autoantibodies, but has good clinical condition, with a peripheral blood count in a normal range, and no new evidence of hematological disease.
While the pathogenesis of autoimmune myelofibrosis is not completely understood, write the case report’s authors, in patients with SLE it may be triggered by circulating immune complexes that induce megakaryocytes to release platelet-derived growth factor. It is likely, they add, that the prevalence of myelofibrosis in patients with SLE is underestimated, given that it responds to the immunosuppressive agents commonly used to treat SLE and because a differential diagnosis between the 2 conditions can be challenging.
Del Porto F, Tatarelli C, Di Napoli A, Proietta M. Systemic lupus erythematosus and myelofibrosis: a case report and revision of literature. Leuk Res Rep. 2018;9:58-64. doi: 10.1016/j.lrr.2018.04.004.