Evaluation of the Automated Blood Bank Instrument QWALYS-3 for Cross-Matching Tests

Koh, Young Eun; Yoon, Jeong; Kwon, Sun hee; Kim, Yoon Ho; Choi, Jae Yeol; Kim, Joo Yeon; Cho, Chi Hyun; Lim, Chae Seung; Yoon, Soo young

Abstract

BACKGROUND
The cross-matching test is regarded as an essential pre-transfusion test. It serves an important role in confirming the ABO/Rh compatibility of transfusion and screening for possible unexpected antibodies. We evaluated cross-matching tests in QWALYS-3 (DIAGAST, Loos Cedex, France), comparing the automated process to manual tube methods.
METHODS
A total of 545 crossmatching tests from 169 patients, collected from RBC concentrate transfusion orders, were performed using both QWALYS-3 and manual tube methods. All patients were follow-up tested later on with antibody identification tests to confirm the presence of unexpected antibodies in plasma.
RESULTS
None of the samples were ABO/Rh incompatible. The presence of unexpected antibodies was later confirmed in 277 tests in 56 patients. Out of those 277 tests, the concordance rate between two methods was 83.8% (232/277). In 268 tests which were later confirmed with no unexpected antibodies, manual tube methods did not show any positive results while five tests were false-positive (5/268, 1.9%) only in QWALYS-3. The overall concordance rate between two methods was 90.82%, and the kappa coefficient was 0.696 (P<0.05) (n=545).
CONCLUSION
The QWALYS-3 system has its merits in accuracy, precision, and lack of possible human errors, however, the automated procedure showed some disadvantages, including relatively low cost-and-time-effectiveness, less effective cold antibody detection, and difficulties in handling small quantity samples. Thus, the QWALYS-3 system has meaningful, but only a limited value in the automation of routine cross-matching tests.