Cold haemagglutinin disease with severe anaemia, reticulocytopenia and erythroid bone marrow.

A quantitative assessment of total, effective and ineffective erythropoiesis, and mean red cell life-span was performed in 2 patients with idiopathic cold-haemagglutinin disease (CHAD) who had severe anaemia, reticulocytopenia and erythroid bone marrow. In both cases, ineffective erythropoiesis represented the major factor in the pathogenesis of the anaemia. The most likely explanation of this was that cold antibodies had some effect on the maturing red-cell precursors. Ineffective erythropoiesis has already been shown in patients affected by auto-immune haemolytic anaemia due to warm antibodies with reticulocytopenia and erythroid bone marrow. Therefore, it is apparent that both warm and cold antibodies may cause not only peripheral destruction of mature red cells but also intramedullary death of red-cell precursors.