Detection of Mycoplasma pneumoniae by two polymerase chain reactions and role of Mycoplasma pneumoniae in pediatric community-acquired lower respiratory tract infections

Purpose: The study was conducted to evaluate the role of Mycoplasma pneumoniae (M. pneumoniae) in children with community-acquired lower respiratory tract infections (LRTIs). Methods: Seventy five children aged 2 months -12 years with community-acquired LRTIs were investigated for M. pneumoniae etiology employing paired serum samples to assay M. pneumoniae antibodies. Nasopharyngeal aspirates were obtained for the detection of M. pneumoniae by using polymerase chain reaction(PCR) and nested PCR. Results: M. pneumoniae infection was positive in 24(85.71%) children aged 5 years and 4 (14.29%) 5???12 years and the difference was statistically insignificant (P = 0.18). Difference in prevalence of M. pneumoniae infection across male and female groups was statistically insignificant (P = 0.69). Clinical and radiological profiles across M. pneumoniae positive and negative cases were comparable except bronchopneumonia which was statistically significant (P = 0.04). Serological evidence of M. pneumoniae infection was observed in 26(33%); PCR was positive in 9 (12%) and nested PCR in 10 (13.33%) children. Together, serology, PCR and nested PCR diagnosed M. pneumoniae infection in 28(37.33%) patients. Sensitivity of serology was 77.78%: specificity 68.18%; positive predictive value 25.00% and negative predictive value at 95.74%. Conclusions: Serological and molecular methods in combination is useful for detection of M. pneumoniae. Our data underline the role of M. pneumoniae in community-acquired LRTIs in children of all ages.