From the Guidelines
Lupus can cause anemia, leukopenia, and thrombocytopenia through autoimmune mechanisms, including the production of autoantibodies that attack blood cells or their precursors, and treatment should focus on controlling the underlying inflammation using corticosteroids, hydroxychloroquine, or other immunosuppressive medications, as recommended by the 2019 EULAR guidelines 1.
Mechanisms of Cytopenias in Lupus
Lupus patients may develop antibodies against red blood cells, leading to their premature destruction (hemolytic anemia), or they may experience anemia of chronic disease due to ongoing inflammation, with impaired iron utilization and reduced erythropoietin production, especially if lupus affects the kidneys 1.
- Leukopenia occurs when autoantibodies target white blood cells or their bone marrow precursors, with neutropenia being particularly common.
- Thrombocytopenia develops when autoantibodies attack platelets or megakaryocytes (platelet-producing cells), causing increased platelet destruction in the spleen or reduced platelet production.
Treatment of Cytopenias in Lupus
According to the 2019 EULAR guidelines, treatment of thrombocytopenia includes high-dose glucocorticoids (GC) and/or intravenous immunoglobulin G, with immunosuppressive/GC-sparing agents such as mycophenolate, azathioprine, or cyclosporine used for maintenance of response 1.
- Refractory cases can be treated with rituximab or cyclophosphamide, as recommended by the guidelines 1.
- Autoimmune hemolytic anemia (AIHA) is treated with GC, immunosuppressive drugs, and rituximab, following the same principles as thrombocytopenia 1.
- Autoimmune leukopenia is common in lupus but rarely needs treatment, with careful work-up recommended to exclude other causes of leukopenia, especially drug-induced 1.
From the Research
Lupus and its Effects on Blood Cells
- Lupus can cause anemia, leucopenia, and thrombocytopenia due to various mechanisms, including immune-mediated and non-immune-mediated processes 2.
- Anemia is found in about 50% of patients with systemic lupus erythematosus, with anemia of chronic disease being the most common form 3.
- Leucopenia, particularly neutropenia, can lead to morbidity and mortality from increased susceptibility to infection, and can be successfully treated with granulocyte colony-stimulating factor 4.
- Thrombocytopenia is a common complication of lupus, occurring in up to 40% of patients, and can be caused by autoantibodies against platelet surface glycoproteins, as well as other factors such as medication and thrombotic microangiopathy 5, 6.
Pathogenesis of Cytopenias in Lupus
- The pathogenesis of cytopenias in lupus is complex and multifactorial, involving autoantibodies, T lymphocytes, and deregulation of the cytokine network 3.
- Impaired erythropoietin response and presence of antibodies against erythropoietin may contribute to the development of anemia in lupus patients 3.
- Thrombocytopenia in lupus is thought to be caused by an excess of platelet destruction and/or reduced production from megakaryocytes, and may be linked to a shared genetic background among various autoimmune diseases 6.
Treatment of Cytopenias in Lupus
- Corticosteroids are the mainstay of initial treatment for immune-mediated hemolytic anemia and severe thrombocytopenia, with immunosuppressive agents such as mycophenolate mofetil or azathioprine often added for their steroid-sparing effects 2.
- Rituximab and intravenous immunoglobulin can be considered for refractory cytopenias, and newer biologic agents such as belimumab or epratuzumab may also be effective 2.
- Treatment of thrombocytopenia in lupus is similar to the treatment of immune thrombocytopenia, and may involve platelet activation and platelet-immune cell interaction as important therapeutic strategies 6.