Blood group genotyping in multi-transfused patients

Aim. To assess the possibility of using blood group genotyping in recipients who received transfusions for 3 months.

Methods. The study included blood samples from 95 patients who received 3 or more erythrocyte transfusions within 3 months. The patients had the following diagnoses: multiple myeloma (n=7), beta thalassemia (n=4), non-Hodgkin's lymphomas (n=11), chronic myeloid leukemia (n=16), primary myelofibrosis (n=9), myelodysplastic syndrome (n=22), acute leukemia (n=21), aplastic anemia (n=5). Red blood cells phenotyping was performed in Diaclon Rh Subgroups+K Gel Cards. The Rh and Kell genotyping was performed by using RBC SSP-PCR kits — FluoGene vERYfy (Inno-train Diagnostics, Germany). The standard RHD/RHCE alleles, as well as polymorphisms associated with KEL1/KEL2 [T698C (Met198Thr)] of the KEL gene were genotyped.

Results. The concordance rate between serological and molecular genetic typing of RhCE and Kell blood groups for donors was 100%, while the patient´s results were discordant in 45.3% of cases. Discrepancies in antigens of the Rh system were registered in 41 patients: one antigen of the Rh system — in 30 patients, two — in 9 patients. Ten patients who had been previously phenotyped as RhCc were genotyped as RHCE*CC. 2 patients who had been previously phenotyped as Rhee were genotyped as RHCE*EE. In 2 patients, antigens D and C were not detected in the phenotype but were identified in the genotype. Discrepancies in antigen K were recorded in 2 patients, and the antigen was absent in the phenotype but was present in the genotype. The genotyping results were confirmed by serological typing at subsequent hospitalizations.

Сonclusion. Blood group genotyping is a useful adjunct to traditional methods when serological typing is limited.