Bacteriology and Antimicrobial Susceptibility of Otitis Media at Dessie Regional Health Research Laboratory, Ethiopia

Background: Otitis media is a major health problem of children in low income countries. Objectives: This study was done to determine the bacterial isolates and antimicrobial susceptibility of otitis media from children and adults. Methods: A retrospective record was analyzed on culture results of discharging ears at Dessie Regional Health Research Laboratory in the period 2003-2010. Antimicrobial susceptibility tests were performed using disc diffusion technique as per the standard Kirby-Bauer method. Results: Out of 897 discharging ear samples, 469 were from children and 428 from adults. Of these, 823 (91.7%) had aerobic bacteria isolated. The most frequent isolates were Proteus spp. 223 (26.5%), S. aureus 203 (24.6%), Pseudomonas spp. 148 (18%) and E. coli 146 (17.7%). Proteus spp. were the most common isolates in children compared to adults (p=0.001). Norfloxacin, ciprofloxacin and gentamicin revealed high level of sensitivity whereas high resistance rates were observed for amoxycillin, tetracycline and erythromycin (p=0.001). Antibiograms of isolates showed that 598 (72.6%) of isolates were resistant to two and more antimicrobials. Conclusion: Otitis media linked with high levels of multiple antibiotic resistant bacteria is a major health concern in all age groups of the study population. There is a need for culture and susceptibility test facilities for appropriate antimicrobial therapy of otitis media and antimicrobial resistant infections. [Ethiop. J. Health Dev. 2011;25(2):161-167]