Type-and-screen analysis
Type-and-screen at delivery was performed in an automated system AutoVue Innova in BioVue Cassettes with anti-IgG (Ortho Clinical Diagnostics, Raritan, NJ, US) in the retrospective analysis, 2010-2012. During the interventional study 2016-2018 the instrument was upgraded to an Ortho Vision, with the same reagents used.
Titration of the 2nd BRITISH STANDARD 1992 Anti-D (Rho) Antibodies (code: 73/515, NIBSC, Potters Bar, UK) in the BioVue Cassettes showed that lower limit of detection (LOD) for anti-D was 10 IU/L (2 µg/L) quantified by flow cytometry. A weak reaction in the screening was defined as < 1+ reaction and corresponded to anti-D 10-20 IU/L (2-4 µg/L).