Comparative Analysis of Clinical Samples Showing Weak Serum Reaction on AutoVue System Causing ABO Blood Typing Discrepancies

BACKGROUND: ABO blood typing in pre-transfusion testing is a major component of the high workload in blood banks that therefore requires automation. We often experienced discrepant results from an automated system, especially weak serum reactions. We evaluated the discrepant results by the reference manual method to confirm ABO blood typing. METHODS: In total, 13,113 blood samples were tested with the AutoVue system; all samples were run in parallel with the reference manual method according to the laboratory protocol. RESULTS: The AutoVue system confirmed ABO blood typing of 12,816 samples (97.7%), and these results were concordant with those of the manual method. The remaining 297 samples (2.3%) showed discrepant results in the AutoVue system and were confirmed by the manual method. The discrepant results involved weak serum reactions (<2+ reaction grade), extra serum reactions, samples from patients who had received stem cell transplants, ABO subgroups, and specific system error messages. Among the 98 samples showing ≤1+ reaction grade in the AutoVue system, 70 samples (71.4%) showed a normal serum reaction (≥2+ reaction grade) with the manual method, and 28 samples (28.6%) showed weak serum reaction in both methods. CONCLUSIONS: ABO blood tying of 97.7% samples could be confirmed by the AutoVue system and a small proportion (2.3%) needed to be re-evaluated by the manual method. Samples with a 2+ reaction grade in serum typing do not need to be evaluated manually, while those with ≤1+ reaction grade do.

Experience in Improving ABO Blood Typing Error at the Blood Donation Site / 대한수혈학회지

BACKGROUND: In the Korean Red Cross Blood Center, ABO blood typing are routinely performed only via red cell grouping at blood donations sites. However, when an error occurs in this process, it is impossible to issue a blood product contrary to the result of the blood type of the Blood Laboratory Center, thereby resulting in delayed supply. Therefore, efforts are needed to reduce typing errors at blood donation sites. METHODS: We analyzed 656,786 donor screenings between January 1, 2016 and December 31, 2016;we also analyzed the statistical data of donor ABO typing between 2013 and 2015. To reduce ABO typing error, we notified and trained nurses at Busan, Gyeongnam, Ulsan, and Daegu-Gyeongbuk Blood centers in June, 2016. We tried to confirm the improvement of ABO typing error at blood donation sites by comparing ABO typing before and after training. For data comparison, chi-square test was conducted (95% confidence interval, 0.05 significant level). RESULTS: The blood typing error rate was significantly lower (P=0.003) four months after training (0.005%) than before training (0.015%), and the blood typing error rate was significantly higher for the first blood donor (P<0.001). CONCLUSION: Educational training for nurses at blood donation sites may be effective in reducing ABO typing error. Continuous and regular training seems to be needed in future to reduce ABO typing error.

Evaluation of IH-1000 for Automated ABO-Rh Typing and Irregular Antibody Screening / 대한수혈학회지

BACKGROUND: Despite modern advances in laboratory automated medicine, work-process in the blood bank is still handled manually. Several automated immunohematological instruments have been developed and are available in the market. The IH-1000 (Bio-Rad Laboratories, Hercules, CA, USA), a fully automated instrument for immunohematology, was recently introduced. In this study, we evaluated the performance of the IH-1000 for ABO/Rh typing and irregular antibody screening. METHODS: In October 2011, a total of 373 blood samples for ABO/Rh typing and 303 cases for unexpected antibody screening were collected. The IH-1000 was compared to the manual tube and slide methods for ABO/Rh typing and to the microcolumn agglutination method (DiaMed-ID system) for antibody screening. RESULTS: For ABO/Rh typing, concordance rate was 100%. For unexpected antibody screening, positive results for both column agglutination and IH-1000 were observed in 10 cases (four cases of anti-E and c, three of anti-E, one of anti-D, one of anti-M, and one of anti-Xg) and negative results for both were observed in 289 cases. The concordance rate between IH-1000 and column agglutination was 98.7%. Sensitivity and specificity were 90.9% and 99.3%, respectively. CONCLUSION: The automated IH-1000 showed good correlation with the manual tube and slide methods and the microcolumn agglutination method for ABO-RhD typing and irregular antibody screening. The IH-1000 can be used for routine pre-transfusion testing in the blood bank.

Evaluation of an Automated Solid-phase Cell Adherence Assay in the Galileo System (Immucor) for Routine Pretransfusion Tests / 대한수혈학회지

BACKGROUND: In spite of a trend of automation for conducting most clinical laboratory tests, many blood banks are still dependent on manual tests. The aim of this study was to evaluate a full automation system called the Galileo (Immucor, USA) for conducting pretransfusion tests. METHODS: From August to October in 2009, a total of 3,002 cases of ABO-RhD typing and 1698 cases of antibody screening were compared between using manual tests and the Galileo system at Seoul National University Hospital, Seoul, Korea. For the manual tests, we used the slide method for ABO-RhD typing and the anti-human immunoglobulin treated microplate method for antibody screening. The Galileo system used the microplate method for ABO-RhD typing and the solid-phase red cell adherence (SPRCA) method for antibody screening. We calculated the overall concordance rate and the false positive or negative rates regarding the manual method as a standard test and the Galileo system as a comparative test. RESULTS: When comparing 3,002 cases of ABO-RhD typing, 52 cases (1.7%) were retested. A discrepancy between the two tests remained in 17 cases (0.6%) after repetition, which led to a concordance rate of 99.4% (2,985/3,002). On the comparison of 1,698 cases of antibody screening, 54 cases (3.2%) were retested. A discrepancy between the two tests remained for 30 cases (1.8%) and the concordance rate was 98.2% (1,615/1,698). Among the 20 false negative cases (1.2%), nine were thought to be cold antibodies with no cases of confirmed warm antibody. CONCLUSION: The automated Galileo system and the preexisting manual tests showed very good concordance for ABO-RhD typing and antibody screening. The Galileo system can be used with confidence for routine pretransfusion tests.