Adverse effect of plasma exchange on anti-D production

Plasmapheresis in Rh Hemolytic Disease: The Danger of Amniocentesis

We have treated 25 women with poor obstetric histories and high levels of anti-Rh antibodies by plasmapheresis during pregnancy. One baby was Rs negative, but 13 of the remaining 24 babies survived. Most of the foetal deaths were associated with a rapid rise in antibody level uncontrollable by plasmapheresis and which followed either amniocentesis or intra-uterine transfusion. Plasmapheresis throughout pregnancy with early delivery and avoidance of amniocentesis is recommended.

The evaluation of maternal anti-D concentrations during pregnancy

Anti-D quantitation by the AutoAnalyzer technique has been shown to be a helpful aid in assessing the severity of D alloimmunization during pregnancy. In this study, the technique has been used both to detect antibody boosting after amniocentesis and to differentiate active D immunization from the presence of passive antibodies. The AutoAnalyzer technique and the more generally used indirect antiglobulin test titration method showed good agreement at titre levels of 32 or lower. A titre of 32 was found to be a good discriminative level to separate the mildly affected from the more severely affected newborns suffering from Rh haemolytic disease. At higher titre levels, however, the AutoAnalyzer technique was the method of choice for correct clinical assessment of the severity of D alloimmunization.