Serous otitis media in children: implication of Alloiococcus otitidis.

OBJECTIVE: Otitis media with effusion (OME) has long been considered to be a noninfective disease resulting from a eustachian tube dysfunction. However, several microbiological techniques have shown bacteria in the middle ear fluids from patients with OME. Alloiococcus otitidis has been detected in the middle ear fluid from patients with OME. The exact role of this infectious agent in the pathogenesis of OME has yet to be elucidated. STUDY DESIGN: A prospective clinical trial. SETTING: A tertiary university-based referral center. PATIENTS: The inclusion criteria included 110 patients aged between 1 and 12 years. The control group included samples obtained from 30 healthy children undergoing a cochlear implantation. The second group included 40 middle ear effusions (MEEs) that were collected from 40 pediatric OME patients during the placement of the ventilation tube. As for the third group, they were 40 children with acute otitis media. Intervention: The bacterial analysis of the MEE was performed by means of microbiological culture-specific techniques. MAIN OUTCOME MEASURE: Positive cultures for A. otitidis as analyzed by bacteriological analysis of samples from the middle ear mucosa and MEE. RESULTS: Bacteria were present in the culture of 72.5% (29) of the patients with OME. Alloiococcus otitidis was the most frequent bacterium in OME (48.27%) as well as Haemophilus influenzae nonserotype B (17.24%). Streptococcus pneumoniae was the most commonly detected pathogen in acute otitis media (37.5%), and then H. influenzae nonserotype B (25%). For most of the OME cases, only A. otitidis bacteria were isolated. CONCLUSION: We observed a high rate of culture positivity for A. otitidis in patients with clinical OME without suppuration. Further studies are needed to confirm whether the association of A. otitidis with OME represents causality. Antibiotic therapy aimed at A. otitidis is complicated by reported resistance, thus emphasizing the importance of our understanding of the pathogenetic role played by this organism