The use of exchange transfusion for the treatment of severe erythroblastosis due to A-B sensitization, with observations on the pathogenesis of the disease.

I N PREVIOUS papers,1 ’ a method of treating erythroblastotic infants by cxchange transfusion was describcd. In the cases reported, the disease had been produced by sensitization to the Rh factor. Despite the publication of several well documented reports,6 it is still not universally appreciated that typical erythroblastosis can also, though rarely, result from sensitization to the A and B factors. The purpose of this paper is to describe two unusual cases of severe erythroblastosis caused by sensitization to the A and B agglutinogens, respectively, which were treated successfully by exchange transfusion. In addition, observations will be described which are of significance with regard to the pathogenesis of such