Use of a PCR-Based Assay for Fetal C^w Antigen Genotyping in a Patient with a History of Moderately Severe Hemolytic Disease of the Newborn Due to Anti-C^w

ABSTRACT

Anti-C^w is an uncommon cause of clinically significant hemolytic disease of the newborn (HDN). We report an unusually severe case of HDN due to anti-C^w that required phototherapy and exchange transfusion. We also describe a novel PCR-RFLP method for C^w typing of fetal genomic DNA that was used for prenatal diagnosis in a subsequent pregnancy. Following PCR amplification of a 163 bp segment of the RHCE gene containing the nucleotide 122 G to A substitution that corresponds to the C^w al-lele, C^w types were distinguished by Taq1 digestion. PCR-RFLP analysis confirmed that the father and previously affected child were C^w-positive. The fetus was C^w-negative, thus excluding HDN in the current pregnancy and obviating the need for further invasive or noninvasive diagnostic procedures for the remainder of the pregnancy. This case illustrates the utility of PCR-based fetal genotype determination in pregnancies at risk of HDN due to uncommon red cell antibodies such as anti-C^w.

Keywords

Hemolytic disease of the newborn (HDN) - C^w antigen - anti-C^w - polymerase chain reaction (PCR) - prenatal diagnosis