The clinical assessment of haemolytic disease of the newborn.

There can be little doubt that at the present stage of our knowledge exchange transfusion is the best method of treating haemolytic disease of the newborn, at least in moderate and severe cases. Recently this viewpoint has been conclusively confirmed by widely based and controlled trials of British workers (Mollison and Walker, 1952; Armitage and Mollison, 1953); their results showed that the mortality of erythroblastotic infants treated by simple transfusions was three times that of those treated by exchange transfusion. In previous years, however, there was a considerable difficulty in differentiating those infants, in whom exchange transfusion was necessary, from those who would not require this radical procedure or any treatment at all. In fact, exchange transfusion is a preventive operation and must be considered soon after birth, i.e., at a time when only severely affected infants show manifest signs of haemolytic disease, most appearing clinically normal. Moreover, the serological findings have appeared to be by no means a reliable index of the post-natal course of the haemolytic disease. The unpredictable prognosis and the relative safety of exchange transfusion made many workers prefer to perform it even in infants who would probably recover without such a precedure. This is not an ideal trend of events and it is obvious that the earlv and reliable assessment of prognosis in any individual case is essential for the correct treatment. The available methods of assessing haemolytic disease of the newborn consist of pre-natal control of pregnant women and the examination of newborn infants immediately after birth. Pre-natally, there are two main points of study: the obstetrical history and the serological findings in the mother. The occurrence of an adequately proved case of haemolytic disease of the newborn in a sensitized woman is almost always followed by the delivery of a more or less affected infant, unless its blood is compatible with maternal antibodies. Most authors assume that in any one family the prognosis of haemolytic disease gets worse in successive Rhpositive infants. Recently Davies, Gerrard and Waterhouse (1953) suggest, on the basis of statistical analysis, that there are two main groups of sensitized women. One, smaller group, tends to have severely affected infants in all successive pregnancies, and the other group tends to deliver infants with only a mild form of the disease. This observation seems to be in agreement with the frequent finding that in some families several mildly affected infants are successively born without an apparent increase in the severity of the disease. On the other hand, the occurrence ofa severe form, i.e., stillbirth, usually signifies an unfavourable prognosis for future births. The relation between the titre and type of maternal antibodies and the severity of the infant's disease has frequently been studied, and some workers still believe that the level of albumin antibodies is the chief factor determining the prognosis and therefore the treatment (Wiener and Wexler, 1949). There is, however, almost general agreement that the prognostic value of serological findings in the mother is somewhat slight: mothers with a high titre of antibodies have the higher probability of delivering an affected child, but exceptions are frequent and interfere with a reliable prognosis in any individual way. In summary, at the present time it is not possible to predict the course of haemolytic disease on the basis of prenatal examination or even to prove actual damage of the foetus, with some exceptions, for example, the x-ray picture of hydrops foetalis.* The value of antenatal control lies in foreseeing the possibility of the haemolytic affection in the newborn. Thus, at birth all measures to confirm the diagnosis can be ready and adequate treatment undertaken within a few hours of birth.