In spite of the availability of effective antimicrobial therapy, Otitis media with effusion (OME) is still an important infection for both children and adults, leading serious health problems. Streptococcus pneumonia is one of the most frequently isolated bacteria from middle ear effusion (MEE) samples of OME patients. Since it is fastidious bacteria, various problems may arise in the rapid diagnosis OME settings. Knowing which bacterium is involved is essential for the prognosis and treatment of otitis media with effusion, as the high frequency of its presentation may be linked to the aetiology and/or course of the process in many patients.
Objective: The aim of this study was to evaluate the use of nested PCR assay for S.pneumoniae as a diagnostic tool in patient with OME and to detect the relation of the organism to other factors contributed to pathogenesis of OME.
Subject and Method Middle ear fluid were aspirated from 34 patients presented with OME. Each sample was subjected to cultivation on selective media, and nested polymerase chain reaction (PCR) test using specific primers directed to selected pneumolysin gene fragment of S.pneumoniae.
Results: S.pneumoniae was recovered by culture in 4/34 (11.87 %) of middle ear fluid samples; 3/4 (75%) from children and 1/4 (25%) from Adults. Nested PCR detectedS.pneumoniae in 11/34 (32.4%) of the samples; 8/11 (72.7%) werechildren and 3/11 (27.3%) were adults. All culture positive samples were PCR positive, but 7 (63.6%) of the PCR positive samples were culture negative. There were strong effects of theage, pervious history of acute otitis media, sinusitis and allergic rhinitis,the recovery rate of the organism (72.7%, 54.5 %, 36.4% and 27.3%) respectively. Conclusion S.pneumoniae was detected in high rates in MEE samples .This suggests that it may play a role in the pathogenesis of otitis media with effusion. In addition, PCR was more sensitive compared to culture for detection of S. pneumoniae in MEE samples.
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