An Experience with Unexpected Antibody Screening Tests using a Panel That Included Di(a) Cells in Koreans

Yun, Seung Gyu; Ryeu, Byung Jun; Yang, Jin Hyuk; Lim, Chae Seung; Kim, Young Kee; Lee, Kap No

Abstract

BACKGROUND
In Korea, a screening panel of cells from abroad without Di(a) positive cells has been commonly used when a patient has an unexpected antibody screening test. It has been reported that Di(a) occurs with a frequency of 6.14 to 14.5% among Koreans. However, the current popular antibody screening panels contain no Di(a) positive cells. In this study, we evaluate the clinical usefulness of the Di(a) Cell Panel (Diagnostic Grifols, Barcelona, Spain) for Koreans.
METHODS
A total of 3,372 pretransfusion samples were employed for unexpected antibody screening testing using panels of cells by the DG Gel microtube column agglutination system, including additional Di(a) cells (Diagnostic Grifols, Barcelona, Spain). The positive cases in this system were confirmed again with DiaMed Di(a) antigen positive panel cells (DiaMed Ag, Cresssier, Morat, Switzerland) and this was followed by sequence- based Diego genotyping.
RESULTS
The positive detection rate of an unexpected antibody screening test using SeraScan Diana I and II was 1.07% (36/3372), and seven samples were reactive (1+~2+) with the SeraScan Di(a) panel cells (0.21%). However, among the 5 available genotyped samples, two cases were typed as Di(a-b+).
CONCLUSION
Even though there is discrepancy between the genotype and the two antibody screening kits, the addition of Di(a) positive cells as unexpected antibody screening panel cells is recommended.