Detection of weak D with a fully automated solid-phase red cell adherence system.
BACKGROUND
Microplate agglutination methods (MAMs) and column agglutination technology are widely employed for red cell typing and can be automated. Some tests, however, such as detection of weak D, require manual testing. The possibility of detecting weak D by a solid-phase RBC adherence (SPRCA) test was studied in a fully automated system.


METHODS
The results of 2609 blood samples, characterized as being D- or with a incomplete agglutination reaction, were analyzed for the presence of the weak D phenotype. The 2609 samples were tested by a weak D tube test (antiglobulin method) and a weak D-test with the new SPRCA method. When weak D was detected, which D epitope was involved and whether it was associated with a partial D phenotype were determined.


RESULTS
Weak D was detected in 60 (2.3%) of the 2609 samples. The 60 samples that were weak D by the tube test were also weak D+ with the new automated SPRCA test. The sensitivity and specificity for the new weak D typing method were 100 percent, when compared with the standard weak D manual test.


CONCLUSIONS
These results support the possibility of performing weak D detection with a SPRCA fully automated system. These preliminary results are encouraging, showing good sensitivity and specificity of the test. Detection of weak D will permit full automation of blood typing.
Lai
Marco
M
Transfusion Center, Clinical Hematology, Catholic University of Sacred Heart, Rome, Italy. marco_lai@fastwebnet.it
Mavilia
Gerarda
G
d'Onofrio
Giuseppe
G
Leone
Giuseppe
G
D000094902:Blood Banking / Q000379:methods; D001788:Blood Grouping and Crossmatching / Q000295:instrumentation / Q000379:methods*; D000939:Epitopes / Q000032:analysis / Q000097:blood; D004912:Erythrocytes; D006386:Hemagglutination Tests / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D010641:Phenotype; D012204:Rh-Hr Blood-Group System / Q000032:analysis / Q000097:blood*; D012680:Sensitivity and Specificity
D000939:Epitopes; D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen