The isohemolytic properties of human blood have been studied from time to time by various observers. Relatively few papers have appeared on this subject, however, in comparison to the large number on the closely related subject iso-agglutination. There is a marked difference in the results reported by different observers on the percentage of occurrence of isohemolysins in the blood of adults. The question of isohemolysins in the blood of new-born infants does not seem to have been investigated adequately. This study was begun to determine if isohemolysins had developed in the blood of new-born infants. It was subsequently extended to include a series of adults for the purpose of comparison under the same conditions of technic.
The first recorded observation on isohemolysis was made by Maragliano1 in 1892. He stated that the serums of persons suffering from essential anemia, carcinoma, malaria, etc., have the property of destroying normal erythrocytes