Polymerase chain reaction to detect Chlamydia trachomatis and adenovirus in the nasopharyngeal aspirates from paediatric patients with lower respiratory infections.

Polymerase chain reaction (PCR) was evaluated to detect Adenoviruses and Chlamydia trachomatis on nasopharyngeal aspirates (NPA) obtained 4-5 days after the onset of lower respiratory tract illness in children. Forty-five nasopharyngeal aspirates (NPA) from 45 children with lower respiratory tract infections were processed for the detection of C. trachomatis and Adenovirus by Fluorescent antibody test (FAT), culture and PCR for the cryptic plasmid of C. trachomatis and the gene coding for hexon of Adenoviruses. Seven (13.3%) and 4 (6.6%) of the 45 specimens were positive for C. trachomatis and adenovirus by PCR respectively, which included one specimen each positive for these agents. Cultures were negative for both the organisms. PCRs showed a statistically significant (McNemar test--p= 0.004) higher sensitivity. PCR test is necessary to detect C. trachomatis and adenovirus in nasopharyngeal aspirates obtained 4-5 days after the onset of illness.