Diagnostic Availability of PCR in the Mycoplasma pneumoniae Pneumonia of Children

Lee, Hyeon Joo; Kim, Eun Sung; Jeong, Hye Jeon; Rha, Yeong Ho; Chung, Sa Jun; Cha, Sung Ho

Abstract

PURPOSE
Mycoplasma pneumoniae is one of the most common causes of pneumonia in children and adolescents. Though cold agglutinin test and specific antibody test are used in the diagnosis of mycoplasma pneumonia, there are some limitations in early diagnosis. In this study, we evaluated the availability and usefulness of polymerase chain reaction (PCR) in the diagnosis of M. pneumoniae pneumonia and compared it with serologic test. METHODS: One hundred twenty four children who were clinically diagnosed with pneumonia and admitted to Kyunghee Hospital from January 1998 to March 2001 were enrolled. Mycoplasma specific antibody test using commercial kit (Serodia-MYCO II, Fusirebio Inc., Tokyo, Japan) and PCR using mycoplasma DNA obtained from throat swabs were done. The sensitivity and specificity of PCR were evaluated. RESULTS: M. pneumoniae pneumonia was diagnosed when the mycoplasma specific antibody titer was over 1: 160 or when the titer increased more than fourfold during follow-up period. The specificity, sensitivity, false-positive rate and false-negative rates of PCR were 93.0%, 58.3%, 33.3%. and 9.7%, respectively. CONCLUSION: PCR has shown high specificity. But, the positive result in PCR don't correlate with the disease activity and PCR does not have high sensitivity. So PCR must be used alongside with serologic test in the diagnosis of pneumonia. But, it seems possible to improve sensitivity by delicate handling of samples and by improving PCR technology, and PCR will possibly be used in the diagnosis of early infections of M. pneumoniae pneumonia and in the evaluation of treatments in the future.