WHO/BS/2017.2322 Report of the WHO Collaborative Study to establish the First IS for Detection of IgG antibodies to Cytomegalovirus (anti-CMV IgG)

Overview

The aim is to develop a CMV IgG antibody (anti-CMV IgG) standard for diagnostic purposes, to improve comparability of the divergent result outputs of current anti-CMV IgG assays.

A WHO collaborative study was conducted with 16 participants from 9 countries using 16 anti-CMV tests of different formats. A candidate standard A1, the anti-CMV IgG reference preparation (A2) of the Paul-Ehrlich-Institut (PEI), and 8 additional study samples with different levels of anti-CMV IgG/IgM and IgG avidity were used. The endpoint titers were determined by linear interpolation at the assay cutoff and by parallel-line-assay. The results were evaluated for potency ratios vs A1, correlation of analytic sensitivity relative to A1 by Spearman's rank correlation coefficient, and spread of the results.