Evaluation of Four Commercial IgG- and IgM-specific Enzyme Immunoassays for Detecting Mycoplasma pneumoniae Antibody: Comparison with Particle Agglutination Assay

Diagnosis of Mycoplasma pneumoniae infection is important due to its variable clinical manifestations and absence of response to beta-lactams. Introduction of enzyme immunoassays (EIAs) for serologic diagnosis of M. pneumoniae has made it possible to separate the analyses of specific IgG and IgM antibodies. We compared four different commercial EIAs, ImmunoWELL IgG, IgM (GenBio), Medac IgG, IgA, IgM (Medac), Platelia IgG, IgM (Sanofi Pasteur), and Ridascreen IgG, IgA, IgM (r-Biopharm) with indirect particle agglutination assay (PA), Serodia-MycoII (Fujirebio). We tested 91 specimens from 73 pediatric patients (2-17 yr) hospitalized at a tertiary-care hospital between December 2005 and January 2006. The measurements of IgM EIAs were correlated with PA titers (Spearman's correlation coefficient, from 0.89 to 0.92) with high concordance rates, ranging from 82.4% to 92.3%. However, some negative IgM-EIA results in PA-positive specimens indicated that serial samplings with convalescent sera would be necessary to confirm M. pneumoniae infection.