Two Different Serologic Mechanisms of Paroxysmal Cold Hemoglobinuria, Illustrated by Three Cases

Abstract

During the last years many examples of paroxysmal cold hemoglobinuria have been described in which attention has been given to the serologic differentiation into two groups, the one (group A) characterized by a biphasic hemolysin, the other (group B) marked by the presence of cold aggluitinin in a very high titer, as was summarized in the report of Becker.³ We should like to stress that the hemolysins of group A, though all of the biphasic type, show many variations as far as concerns thermostability, optimal period of the cold phase and the need of complement for the fixation of the antibody in the cold. In our own case the hemolysin behaved differently from those earlier described in that it reacted only with the patient’s cells and not with others. In addition it was found that the hemolysin reacted with P.N.H. cells as a monophasic warm antibody. Next to the hemolysin an incomplete cold antibody of an unusual type was present in the serum of the patient. It is suggested that this antibody is not identical with the hemolysin and of minor importance for the hemolytic process. In group B the cold agglutinins predominated, but apart from these a monophasic warm hemolysin could be demonstrated in the serum of 2 patients. In both groups (A and B) the complement was reduced or even absent, indicating that hemolysins played an active role in the red cell destruction, although in group B the major importance is given to the cold agglutinins. Therefore transfusions with fresh whole blood could be harmful, because this might result in adding complement to the patient’s blood and provoke hemolysis of the patient’s own cells as well as of the transfused cells. In all cases of paroxysmal cold hemoglobinuria of both types and of other hemolytic anemias the possible influence of complement should be considered in regard to the serologic mechanism and blood transfusion therapy.