Implementation of gel column technology, including comparative testing of Ortho ID-MTS with standard polyethylene glycol tube tests.

With the intent to increase laboratory efficiency and according to the Clinical Laboratory Improvement Act of 1988 (CLIA '88), a parallel testing program comparing traditional tube technology with the gel system technology was undertaken. Test tube indirect antiglobulin tests were performed using polyethylene glycol (PEG) as the antibody enhancement medium. Gel (GEL) column technology used the ID-Micro Typing System, using predispensed anti-IgG and low-ionic- strength saline for antibody enhancement. Tests were performed as described in the manufacturer's guidelines and the current edition of the Technical Manual of the American Association of Blood Banks. Testing included antibody detection, antibody identification, direct antiglobulin tests (DATs), antigen phenotyping (K, Fya, Fyb, S, and s), and elution studies. These procedures were evaluated for sensitivity, specificity, and efficiency. Sixty-six samples that had been tested for antibody activity by PEG tube techniques were evaluated by GEL. These samples included 49 that were nonreactive and 17 with a positive antibody detection test. Within the latter were 19 antibodies, 17 with specificities considered to be clinically significant and 2 usually considered clinically insignificant for red cell transfusion. GEL was nonreactive with the 49 PEG negative samples as well as with the 2 samples containing insignificant antibody. All 17 antibodies of probable clinical significance were detected. Antibody identification studies were performed on these latter samples, with GEL results consistent with PEG tube results in all cases. Concordant results were obtained with 10 of 10 DATs (7 negative, 3 positive), all 77 antigen phenotyping tests (37 negative, 40 positive), and the 6 parallel elution studies (4 negative, 2 positive). GEL testing was found to be comparable or better when compared with PEG tube testing in all procedures evaluated.