Abstract
In this study we assessed the efficacy of the microcolumn gel method in the detection and quantification of the volume of fetomaternal hemorrhage (FMH) in comparison with the Kleihauer-Betke test (KB) in nonisoimmunized D– mothers. We collected blood samples from 80 D– indirect antiglobulin test–negative mothers over a span of more than 1 year. FMH was determined by KB and microcolumn gel method, and the results were compared. FMH was recorded as less than 4 mL by KB if no fetal cells were seen after examining 25 fields using 10× objective. If fetal cells were seen, slides were examined further to quantify FMH. By microcolumn gel method, FMH was reported as less than 0.1 percent, 0.1 percent, 0.2 percent, and 0.4 percent or greater. None of the patients had FMH greater than 15 mL by KB. Sixty-two patients (77.5%) had FMH less than 4 mL by KB. In all these cases, FMH was less than or equal to 0.2 percent (approximately 4 mL) by microcolumn gel method. The mean volume of FMH in the remaining 18 (22.5%) cases by KB was 8.3 ± 1.7 mL. Fifteen (83.3%) of these 18 cases had FMH of at least 0.4 percent (approximately 8 mL) by gel technology. Three cases (16.7%) that differed from KB results had FMH of 0.2 percent by microcolumn gel method with a maximal FMH of 6.4 mL by KB. FMH was significantly increased in cesarean delivery (mean FMH 9.5 ± 0.8 mL, range 7.9–10.4 mL, p = 0.001) and antepartum hemorrhage (mean FMH 9.5 ± 0.9 mL, range 7.9–10.4 mL, p < 0.001). Microcolumn gel method is an effective screening test. Technologies like KB and flow cytometry are better options for detecting a large volume of FMH. Antepartum hemorrhage and cesarean delivery are risk factors for FMH. The 300-µg dose appears to be excessive immunoprophylaxis in the majority of cases. We need to analyze the relative cost-effectiveness of universal administration of 300 µg of Rh immune globulin vs. FMH quantitation with subsequent administration of titrated doses. Immunohematology2013;29:105–09.