A Concise Review of Autoimmune Cytopenias in Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) is frequently associated with autoimmune complications such as autoimmune hemolytic anemia, immune thrombocytopenia, pure red cell aplasia, and autoimmune granulocytopenia. It is critical to diagnose cytopenias from these secondary complications of CLL accurately, since prognosis and therapy are substantially different from patients who have cytopenias due to extensive bone marrow infiltration by CLL. The pathogenesis of autoimmune cytopenias in CLL is complex; and it involves antigen presentation by CLL cells to polyclonal B cells resulting in production of autoantibody, and alteration of the T cell milieu tilting the balance in favor of an autoimmune response. Traditional therapy of autoimmune complications in CLL consists of immunosuppression with corticosteroids and/or anti-CD20 monoclonal antibodies. In patients who have a suboptimal response, treating the underlying CLL is generally effective in ameliorating secondary cytopenias. Although novel oral therapies such as ibrutinib, idelalisib, and venetoclax have been shown to be extremely effective in the management of CLL, prospective data from larger numbers of patients with longer follow-up are needed prior to recommending their routine use in the management of autoimmune cytopenias in CLL.