Intralaborvergleich zur Bestimmung der Äquivalenz zweier automatisierter Methoden

: Festphasenagglutinations- und Säulenagglutinationstechnik

Abstract

The InnKlinikum Altötting is replacing its immunohaematological equipment from Immucor Med. Diagnostik GmbH to Ortho Clinical Diagnostics. The solid-phase agglutination technique previously used will therefore be replaced by the column agglutination technique. As the German Medical Association requires a validation of the examination procedures used in the guideline for quality assurance of laboratory medical examinations (Bundesärztekammer, 2022), the new test procedure was tested for equivalence to the existing procedure. 74 anonymised test samples were used, which were determined by the EchoLumena and OrthoVision in AB0 blood group, Rhesus and Antibodyscreening. Percentage agreement and the kappa coefficient were used for statistical analysis. Of 74 samples, 66 results were concordant in the blood group determination, 74 concordant in the rhesus determination and 71 concordant in the Antibodyscreening. This results in a concordance of 89.19 % (k = 0.853) for the AB0 determination, 100 % (k = 1) for rhesus and 95.9 % (k = 0.7784) for the Antibodyscreening. The agreement of positive results in the Antibodyscreening showed 66.7 % and for negative results 100 %. For the determination of isoagglutinins, plasmas were measured at different dilution levels on both devices. The EchoLumena was able to determine anti-A1 up to a dilution of 1:4 and antiB in the undiluted and 1:2 dilution with a questionable reaction. Higher dilutions were negative. The OrthoVision was able to determine anti-A1 up to 1:128 and anti-B up to 1:32. For the detection of mixed blood, A and 0 erythrocytes and B and 0 erythrocytes in different mixing ratios were determined on both devices for the A and B antigens. The EchoLumena showed the mixed field in anti-A from a 0 proportion of 40 % and in anti-B from 60 %. The OrthoVision showed the mixed field in anti-A from a 0 proportion of 30% and in anti-B from a 0 proportion of 20%. The EchoLumena and OrthoVision devices generally showed moderate to perfect agreement and are similar to the results of similar comparative studies. On closer examination, the discrepant results were not considered clinically relevant.

Date of Award	2025
Original language	German (Austria)
Awarding Institution	FH Gesundheitsberufe OÖ GmbH
Supervisor	Harald Maier (Supervisor) & Manuel Holzer (Supervisor)