Auto-immune haemolytic anemia complicating infectious mononucleosis in a patient with hereditary elliptocytosis.

Auto-immune haemolytic anemia complicating infectious mononucleosis occurred in a patient with hereditary elliptocytosis. A cold antibody of IgM anti-i specificity with narrow thermal amplitude was identified in the serum and the erythrocytes were found to be coated with complement. Significantly excessive erythrophagocytosis was demonstrated in samples of the patient's blood which had been chilled and then incubated at 37 degrees C. The patient recovered spontaneously. The elliptocytosis does not appear to have contributed to the episode of haemolytic anaemia; the other elliptocytic member of the family (her father) had no history and no present evidence of haemolysis.