Guidelines of the Croatian Society for Transfusion Medicine for Determination of Rh (D) Blood Group and Application of RhD Genotyping

The working group of the Croatian Society for Transfusion Medicine has prepared guidelines for the determination of Rh (D) blood group and the application of RhD genotyping. The guidelines describe clinical significance of D antigen, history and limitations of serological testing for D antigen, and possibility of RhD genotyping. The aim of the guidelines is to publish new procedures for serological determination of Rh (D) blood groups in patients, pregnant women and newborns with instructions for transfusion medicine specialists in emergency and regular work, and interpretations of findings for gynecologists, pediatricians, neonatologists, anesthesiologists, internists, and physicians who in their work meet patients who receive blood products and decide on the use of RhIG immunoprophylaxis. As a result of implementation of the guidelines, monitoring and periodic reporting in case of suspicion of RhD immunization in a person carrying the D variant is envisaged. During pregnancy there is a possibility of non-invasive determination of prenatal fetal RhD genotype from maternal plasma after the 16th week of gestation, as an important tool in assessing the risk of developing hemolytic disease of the fetus and newborn. For ease of reference, the types of blood sampling containers and the required quantity of samples are listed. This test is available at the Croatian Institute of Transfusion Medicine at the request of a gynecologist and is recommended primarily to RhD immunized pregnant women, and in case of decisions on early prenatal anti-D immunoprophylaxis for all Rh (D) negative non-immunized pregnant women.