[Immunohemolytic complications observed during transfusion of more than 2 million units of blood].

From 1955 through 1978, 150 immunohemolytic accidents of variable gravity have been documented, representing an incidence of 7.1 cases out of 100 000 transfused blood units. These accidents can be classified as follows: 83 cases due to ABO incompatibility, 42 cases due to an irregular antibody in the recipient (six times due to anti-D), 20 cases induced by passive maternal antibodies in the newborn and 5 cases which were attributed to injected anti-A or anti-B antibodies. Ten deaths were recorded, all ascribed to ABO (8 cases) and to Rhesus D (2 cases) incompatibilities. In the present study, a major decrease in the incidence of ABO accidents has been observed, especially since 1966 with systematic controls being performed at the patient's bedside. However, irregular antibodies were the cause of the conflicts in only 10% of the cases when the study was started, and is now incriminated in 8 cases out of 10.