A multicenter study on the performance of a fully automated, walk-away high-throughput analyzer for pretransfusion testing in the US population.

BACKGROUND

Moving to automation is a major focus of transfusion centers. Erytra (Grifols) is a walk-away analyzer with high-performance and -throughput capacity for pretransfusion testing. Efficiency and performance of Erytra with its cards and reagents were evaluated in comparison to Food and Drug Administration (FDA)-approved reference methods.

STUDY DESIGN AND METHODS

A total of 5279 blood samples (46% patients; 54% donors) were obtained from US blood establishment facilities. Samples were analyzed with Erytra and results were compared with the routine FDA-licensed automated platforms used by the clinical study sites. A total of 25,217 tests were performed (15,322 ABO/D/reverse typing; 4916 Rh phenotypes, 669 K typing, 838 antibody screens, 759 antibody identifications, 250 cross-matches, 244 ABO compatibilities by immediate-spin cross-match, and 219 direct antiglobulin tests [DATs]).

RESULTS

Global agreement between Erytra and the comparison platforms was 99.66%, with 99.82% positive percent agreement (95% lower confidence bound [LCB], 99.75%) and 99.50% negative percent agreement (95% LCB, 99.37%). There were 85 discrepancies (0.34%), including cross-matches (n = 13), antibody screens (n = 10), antibody identifications (n = 21), and DATs (n = 5), whereas an excellent concordance was obtained in blood grouping determinations (ABO/D/C/E/c/e/K, 0.04%-0.22% discrepancies). Analysis of the discrepancies showed that Erytra provided the correct result in 51 of them (60%), with only five false negatives (one O patient transplanted with A, one mixed-field reaction in a very weak D, one anti-Vel, two A2rr). Erytra results were 100% reproducible in a series of 3760 repetition tests.

CONCLUSION

Grifols' Erytra analyzer showed reliable efficacy compared with equivalent FDA-licensed reagents and FDA-cleared instruments.