The first fully automated allergy analyser UniCAP: comparison with IMMULITE for allergy panel testing

Abstract

Automated immunoassay systems should be convenient to handle, flexible and give reliable results. To investigate the extent to which the UniCAP System met the above requirements, compared with the IMMULITE System, we compared the Phadiatop (UniCAP) and AlaTOP (IMMULITE) results of 110 patients with positive clinical diagnoses for inhalant allergy. In addition, we compared food screening test results of 103 patients with a clinical positive diagnosis for food, and 110 test results of controls with negative diagnosis for allergy. Phadiatop had a sensitivity of 96% and a specificity of 92%. AlaTOP had a sensitivity of 86% and a specificity of 94%. For food screening the results were: 75% sensitivity and 82% specificity for fx5 (UniCAP) and 63% sensitivity and 71% specificity for fp5 (IMMULITE). Furthermore, those samples for which the test results which were not in concordance with the clinical diagnosis were tested with the follow-up panel of the different screening tests. For the AlaTOP follow-up we had to use the DPC microplate System (Milenia), because single allergen testing is not yet possible on the IMMULITE System. With regard to sensitivity, the UniCAP specific inhalant allergen tests and the original Phadiatop results showed closer agreement with each other than did the Milenia specific allergen results with the AlaTOP. The specificity of the single inhalant allergen tests was the same for both systems. For food allergy testing the UniCAP System shows closer agreement between the screening and the follow-up results than does the IMMULITE. The hands on time for loading 44 samples was practically the same for both systems, but for the follow-up tests the Milenia System is used next to the IMMULITE. Therefore from a logistical point of view the UniCAP System is more convenient. From these results we conclude that both logistically and clinically UniCAP seems to meet our requirements better than the IMMULITE.