Résumé
PURPOSE: The diagnosis of Mycoplasma pneumoniae (M. pneumoniae) infection is usually based on serology using complement fixation assay (CFA), particle agglutination test (PA), enzyme immunoassay (EIA) and polymerase chain reaction (PCR). The objective of this study is to compare the performance of EIA and PCR in diagnosis of M. pneumoniae infection. We also evaluated the usefulness of EIA which were checked on short-term follow-up (3-5 days). METHODS: We included 234 pneumonia children. We used serum specimens for EIA test, which were obtained on admission and 3-5 days after admission. We collected throat swabs or sputums for PCR test, which were obtained on admission or next morning after admission. RESULTS: Of 234 patients, 124 (53.0%) met the diagnostic criteria. The median age was 6 years (from 10 months to 12 years). On admission, the sensitivity and specificity of EIA-specific IgM were 46.1% and 72.8%, respectively. The rate of agreement between PCR and EIA was 64.1%.(kappa=0.187, P=0.004) On 3-5 days after admission, the sensitivity and specificity rates of EIA specific IgM were 85.5%, 69.6%, respectively. The rate of agreement between PCR and EIA was 74.8%.(kappa=0.490, P=0.000) Days after onset had no relation with sensitivity of EIA.(P>0.05) The sensitivity and specificity rates of PCR were 57.5% and 90.0%, respectively. CONCLUSION: This study suggests that PCR and EIA may be the useful diagnostic methods for detecting early phase of M. pneumoniae infection. And EIAs which checked on short-term follow up is also useful. PCR has shown a higher specificity but lower sensitivity. Therefore, PCR must be performed with serologic tests.