Amount of Haemophilus influenzae Genomic DNA in Middle Ear Fluids ofPediatric Acute Otitis Media

Background: Nontypeable Haemophilus influenzae (NTHi) is a leading causative pathogen responsible for acute otitis media (AOM). Objective: In this study, we applied real-time PCR to quantify the amount of genomic NTHi DNA in MEEs and to evaluate the influence of the amount of bacteria in MEEs on the clinical outcome of AOM. Methods: Thirty-two children with severe AOM were evaluated for the quantification of the amount of NTHi genomic DNA in middle ear effusions (MEEs) by real-time PCR. Results: The improvement of tympanic membrane abnormalities at the second visits was significantly worse in cases with MEEs containing dense NTHi genomic DNA rather than in cases with MEEs containing sparse NTHi genomic DNA. The amount of NTHi DNA genome in MEEs were significantly higher in cases of which improvement ratio of tympanic membrane abnormalities at the second visit was less than 50% than in cases of which improvement ratio of tympanic membrane abnormalities above 50%. Discussion: It is important to predict the clinical futures of AOM for appropriate treatments. The quantity of infected pathogens will be an important factor for poor clinical outcomes of AOM. Conclusion: The current findings suggest that severity of tympanic membrane abnormalities evaluated scoring system proposed by Japanese AOM guideline reflect the amount of NTHi in MEEs and that predict the poor improvement of AOM.