Kim Tae Yeul, Hong Yun Ji, Kim Mi Jung, Kim Hyungsuk, Kim Taek Soo, Park Jeong Su, Park Kyoung Un, Han Kyou-Sup
Department of Laboratory Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
Transfus Med Hemother. 2020 Feb;47(1):88-93. doi: 10.1159/000500098. Epub 2019 May 17.
DEL, the weakest D variant, is mistyped as D-negative by routine serological assays. Transfusion of red blood cells expressing the DEL phenotype has the potential to elicit anti-D alloimmunization in D-negative recipients. The goal of this study was to recommend DEL typing strategies for serologically D-negative Asian donors.
RhCE phenotyping and the adsorption-elution test were performed on 674 serologically D-negative samples. genotyping using real-time polymerase chain reaction and melting curve analysis were also undertaken to identify DEL alleles. Costs and turnaround time of RhCE phenotyping, the adsorption-elution test, and genotyping were estimated.
Sensitivity and specificity of the adsorption-elution test for serologically D-negative samples were 94.9% (93/98) and 91.5% (527/576), respectively. C+ phenotypes were detected in all 98 samples with DEL alleles. Despite comparable costs, genotyping was more accurate and rapid than the adsorption-elution test.
Two practical DEL typing strategies using RhCE phenotyping as an initial screening method were recommended for serologically D-negative Asian donors. Compared with DEL typing using genotyping, serological DEL typing using adsorption-elution test is predicted to increase the incidence of anti-D alloimmunization and decrease the D-negative donor pool without having any cost-competitiveness but can be used in laboratories where molecular methods are not applicable.
DEL是最弱的D变异型，通过常规血清学检测会被误判为D阴性。向D阴性受血者输注表达DEL表型的红细胞有可能引发抗-D同种免疫。本研究的目的是为血清学D阴性的亚洲献血者推荐DEL分型策略。
对674份血清学D阴性样本进行RhCE表型分析和吸附洗脱试验。还采用实时聚合酶链反应和熔解曲线分析进行基因分型以鉴定DEL等位基因。估算了RhCE表型分析、吸附洗脱试验和基因分型的成本及周转时间。
吸附洗脱试验对血清学D阴性样本的敏感性和特异性分别为94.9%（93/98）和91.5%（527/576）。在所有98份带有DEL等位基因的样本中均检测到C+表型。尽管成本相当，但基因分型比吸附洗脱试验更准确、更快速。
对于血清学D阴性的亚洲献血者，推荐了两种以RhCE表型分析作为初始筛查方法的实用DEL分型策略。与采用基因分型的DEL分型相比，使用吸附洗脱试验进行血清学DEL分型预计会增加抗-D同种免疫的发生率并减少D阴性献血者库，且没有任何成本竞争力，但可用于无法采用分子方法的实验室。
