Antimicrobial susceptibility patterns of bacteria isolated from patients with ear discharge in Jimma Town, Southwest, Ethiopia.

Background: Otitis media is among the leading causes of childhood illnesses although it can also affect the adults resulting in frequent physician visits, drug prescription and a key contributor to antibiotic resistance. The aim of this study was to determine the risk factors, bacterial profile, and the antimicrobial susceptibility pattern of the isolates from patients with discharging ears which clinically equates to draining otitis media in developing countries with limited medical resources such as otoscope.

Methods: A prospective cross-sectional study was conducted on 173 patients with draining otitis media. The ear discharge specimens were collected and analyzed by standard microbial techniques. The antibiotic susceptibility profiles were determined for 19 different antibiotics by the standard disk diffusion method. Data was analyzed by SPSS version 22 and the P value of less than 0.05 was considered as statistically significant.

Results: Among 173 otitis media patients participated in the study; majority, 102(63%) were pediatrics, out of which 72 (41.61%) were in the age group of less than 4 years. Ear infection was bilateral in 39 (22.54%) and chronic in 100 (57.8%) of the patients. Pathogens were isolated from 160 (92.5%) of the patients with a total of 179 isolates. The predominant isolate was Staphylococcus aureus (30.72%) followed by Proteus spp. (17.89%). The result of this study showed that adult age (p = 0.031), rural residence (p = 0.005), previous history of health care visit and treatment (p = 0.000), upper respiratory tract infection (p = 0.018) and presence of cigarette smoker in the house (p = 0.022) had statistically significant association with chronic otitis media. Most of the isolated bacteria showed high level of resistance to ampicillin/amoxicillin (88.3%), penicillin G (79.5%) followed by trimethoprim /sulfamethoxazole (73.8%). Conversely, the majority of bacterial isolates showed moderate susceptibility to ciprofloxacin (72.9%), gentamicin (70.4%), and amikacin (69.3%). Bacterial isolates identified in this study showed trend of multiple drug resistance, majority (67%) being resistant to three or more antimicrobials.

Conclusions: Majority of the bacterial isolates were multidrug resistant, hence, efforts to isolate microorganisms and determine the susceptibility pattern should be strengthened to improve the treatment outcome of otitis media instead of the usual trend of empirical treatment.