Lack of Chlamydophila pneumoniae and predominance of Alloiococcus otitidis in middle ear fluids of children with otitis media with effusion

Objective: To investigate the presence of Chlamydophila pneumoniae and other bacterial pathogens in middle ear effusion samples obtained from children with otitis media with effusion (OME). Materials and methods: Twenty-eight children (mean age 7.03; standard deviation 2.18) with OM E unresponsive to medical therapy were included in the study. All of the children underwent ventilation tube insertion under general anesthesia. Eighteen patients were bilaterally affected whereas 10 children had unilateral disease. The middle ear fluids (46 samples in total) were collected during ventilation tube insertion, and were evaluated subsequently for the presence of C. pneumoniae and other bacterial pathogens using polymerase chain reaction (PCR). Results: Although all samples were negative for C. pneumoniae. bacterial DNA was detected in 21 of 46 samples. Overall 40% of the patients (4/10) with unilateral involvement, and 61% of the patients (11/18) with bilateral involvement were positive for bacterial DNA. In 6 patients with bilateral OME bilateral samples were positive, whereas 5 patients with bilateral OM E showed only unilateral positivity. According to the results of DNA sequencing analysis, all of the positive samples harbored only one bacterial species. In 12 of 46 samples Alloiococcus otitidis DNA (26%), in 7 Haemophilus influenzae DNA (15%), in one Streptoccoccus pneumoniae DNA (2%) and in one Moraxella catarrhalis DNA (2%) were present. Conclusions: Our findings support that C. pneumoniae does not seem to have a role in OM E in children whereas A. otitidis was found to be more frequent than the other common pathogens. Further studies are required to elucidate the exact pathogenetic role of these microorganisms in OME. (C) 2009 Elsevier Ireland Ltd. All rights reserved.