Comparison of PCR, culture, and serological tests for diagnosis of Mycoplasma pneumoniae respiratory tract infection in children

For diagnosis of Mycoplasma pneumoniae infection we compared two rapid test s, PCR and the immunoglobulin M immunofluorescence assay (IgM IFA), with cu lture and the complement fixation test (CFT), in a prospective study among 92 children with respiratory tract infection and 74 controls. Based on posi tivity of culture and/or CFT as the diagnostic criterion, nine patients (10 %) were diagnosed with M, pneumoniae infection. All patients positive by cu lture were also positive by PCR, In all controls cultures, PCRs, and serolo gical assays were negative, except in one with a positive IgM IFA, The IgM IFA had a low positive predictive value of 50%. Only a combination of PCR ( seven patients) and CFT (seven patients) allowed diagnosis of all cases.