November/December 2020 EuroLabNews

6. Updates on EFLM publications

6.3. Harmonization of antineutrophil cytoplasmic antibodies (ANCA) testing by reporting test result- specific likelihood ratios: position paper

Bossuyt X, Damoiseaux J, Rasmussen N, van Paassen P, Hellmich B, Baslund B, Blockmans D, Vermeersch P, Lopez-Hoyos M, Vercammen M, Barret E, Hammar F, Leinfelder U, Mahler M, Olschowka N, Roggenbuck D, Schlumberger W, Walker R, Rönnelid J, Cohen Tervaert J-W, Csernok E, Fierz W for (i) the European Federation of Laboratory Medicine (EFLM) Task and Finish Group “Autoimmunity Testing,” (ii) the European Autoimmune Standardization Initiative (EASI) and the (iii) European Consensus Finding Study Group on autoantibodies (ECFSG)

Clin Chem Lab Med 2020; Available from:

Reported by Lejla Alić, member of the EFLM WG-Promotion & Publications
Recently, many high-quality immunoassays for proteinase-3 and myeloperoxidase antineutrophil cytoplasmic antibodies (ANCA) have . Although reference materials and standards are available for measurements, studies have shown that the harmonization of ANCA test results reporting is an open question. In this position paper authors propose harmonization of reporting test results of ANCA immunoassays using test-results specific likelihood ratios (LR). ight different immunoassays using 924 disease controls (suspected for ANCA-associated vasculitis) and 251 diagnostic samples (confirmed ANCA-associated vasculitis, AAV). The test results-specific LRs were estimated using derivative of the receiver operating characteristics (ROC) curve and by Bezier curves. Authors propose reporting of the test results as LR of 0.1, 1, 10, and 30a