Acquired Pure Red Cell Aplasia Associated with Chronic Myelomonocytic Leukemia: Too Many of One, Not Enough of the Other

There is a growing body of literature outlining the association between certain hematological malignancies, such as chronic myelomonocytic leukemia (CMML), and systemic autoimmune diseases. Diagnosis and management can be difficult, particularly when autoimmune phenomena overlap with features of the underlying illness. This is especially the case in patients who develop immune-mediated cytopenias in the context of underlying bone marrow disease. CMML associated with immune thrombocytopenia and hemolytic anemia has been reported a number of times in the literature; however, there are only scattered case reports describing CMML associated with acquired pure red cell aplasia. Here, we describe the diagnostic and management approach to a patient who developed both diseases.