HLA Typing Proficiency Survey in Korea, 2003-2004

Lim, Ji Hun; Hwang, Sang Hyun; Oh, Heung Bum

Abstract

BACKGROUND
HLA proficiency survey in Korea started in 1996 and the results of the survey were last reported in 1999. In this report, we summarized the results of the survey performed in recent 2 years. METHODS: A total of four proficiency surveys were performed, in which 54-59 laboratories participated. Each survey included 3 tests for HLA class I (serology and DNA) and class II (DNA) typing and 6 for HLA crossmatch test (3 cells x 2 sera). RESULTS: Overall concordance of serologic typing was 99.5% (436/438) for HLA-A, 95.7% (419/438) for HLA-B, and 94.8% (199/210) for HLA-C. The antigens assigned incorrectly by more than 5% of the participating laboratories were B54 (10.3%), B55 (10.3%), B27 (5.4%), Cw6 (22.9%), and C-blank (5.7%). Overall concordance rates of DNA typing were 99.7% (393/394) for HLA-A, 99.8% (415/416) for HLA-B, 100% (156/156) for HLA-C. Correct assignment of HLA-DRB1 and -DQB1 was reportred by 99.7% (98.1-100%) and 99.2% (88.9-100%) for generic and 99.2% and 98.1% (80-100%) for allelic level, respectively. Most laboratories (93.5-97.9%) were using sensitive methods of crossmatch such as T-long, T-AHG, and flowcytometry. The proportion of laboratories evaluated as unacceptable was on the average 3.1% of total laboratories. CONCLUSIONS: The rate of correct identification of HLA antigens was higher this time than in the previous survey in 1999. The rate of unacceptable crossmatch was also low enough to be satisfactory. It is thought that the proficiency survey has contributed to the high quality of HLA tests in the participating laboratories and should be continued to maintain the proficiency in Korea.