Pathogenic bacteria profile and antimicrobial susceptibility patterns of ear infection at Bahir Dar Regional Health Research Laboratory Center, Ethiopia

Abstract

Ear infection linked with frequent antibiotic prescription, hearing impairment, severe disability and death is a public health threat in developing countries. However, there is scarcity of documented data in the study area. Therefore, this study aimed at determining bacterial etiologic agents and their antimicrobial susceptibility patterns among patients of all age groups referred to Bahir Dar Regional Health Research Laboratory Center. Retrospective data recorded on culture and antimicrobial susceptibility profile were retrieved for analysis. Pus swabs from discharging ears collected and processed for aerobic bacteria culture and susceptibility testing. Of the total 368 pus swab samples processed, 296 (80.4 %) were culture positive. Of which, 289 (97.6 %) were bacteria and 7 (2.4 %) were yeast cells. The proportion of ear infection was higher in males (92.7 %) than females (65 %) (P = 0.014). The frequency of ear infection below 21 years of age was 65.2 %. The predominant isolate was Pseudomonas aeruginosa (29.7 %) followed by Staphylococcus aureus (26.3 %) and Proteus spp. (21.9 %). High level of antimicrobial resistance rates were observed for amoxicillin/clavulanic acid, ampicillin and penicillin whereas ciprofloxacin, ceftriaxone, chloramphenicol, cotrimoxazole, gentamicin and amikacin were found effective against the isolated bacteria. Aerobic bacterial otitis media linked with high levels of resistance against amoxicillin/clavulanic acid and ampicillin is major health problem in the study area. Moreover, considerable level of oxacillin resistant S. aureus suggests the diffusion of methicillin resistant S. aureus in the community. Therefore, treatment of otitis media in the study area needs to be guided by antibiotic susceptibility testing of isolates.

Spectrum of Microbial Isolates from Wound Infections in Patients admitted in a Tertiary Care Hospital, Kolkata

“…Though different studies throughout the world demonstrated poor correlation among the different methods of testing for polymyxin B and colistin, but some studies including our study demonstrated good correlation because of use of validated broth dilution method. Our study demonstrated that P. mirabilis (n = 55) was highly sensitive to piperacillin-tazobactam (90.90%), imipenem (83.63%), moderately sensitive to cefoperazonesulbactam (65.45%), ertapenem (65.45%), aminoglycoside group of antibiotics (60-69%), chloramphenicol (63.63%) which was partially similar to the studies done by Hailu et al, 33 Seid et al, 36 and Wasihun and Zemune. 39 These studies demonstrated low level of resistance (5-28%) to ciprofloxacin, piperacillin-tazobactam, ceftazidime, gentamicin, and ceftriaxone.…”

“…The study showed 40 to 90% resistance to co-trimoxazole, chloramphenicol, ciprofloxacin, erythromycin with only 30% resistance to clindamycin, whereas only 0 to 31% resistance to ciprofloxacin, chloramphenicol, clindamycin, erythromycin, and co-trimoxazole was evidenced in the study done by Hailu et al, 33 Seid et al, 36 Abera and…”

“…to 100% isolates of MRSA were resistant to penicillin and methicillin group of antibiotics, whereas in the study of Hailu et al, 33 65.4 and 34.6% S. aureus demonstrated resistance to penicillin and oxacillin respectively with more or less similar results were found in the study done by Hwang et al, 34 Abera et al, 35 and Seid et al 36 Our study as well as other different studies suggest that a largescale study is required on the prevalence and spectrum of susceptibility of community-acquired MRSA. The study showed 40 to 90% resistance to co-trimoxazole, chloramphenicol, ciprofloxacin, erythromycin with only 30% resistance to clindamycin, whereas only 0 to 31% resistance to ciprofloxacin, chloramphenicol, clindamycin, erythromycin, and co-trimoxazole was evidenced in the study done by Hailu et al, 33 Seid et al, 36 Abera and…”

“…38 More or less similarity in observations was demonstrated in the study of Perim et al 31 In our study, Pseudomonas was 100% resistant to ampicillin, amoxicillin, tetracycline, erythromycin, cefotaxime, clindamycin, vancomycin, teicoplanin, linezolid and around 50% resistant to aminoglycoside group of antibiotics. In the study, of Hailu et al, 33 it was demonstrated that P. aeruginosa was highly sensitive to ciprofloxacin, gentamicin, amikacin, and chloramphenicol. This was contrary to our study where Pseudomonas was 52 to 55% sensitive to gentamicin, amikacin, ciprofloxacin, whereas 5.21% sensitive to chloramphenicol.…”

“…Similarly, our study indicated very low level of sensitivity to ampicillin, amoxicillin, oxacillin which was also evidenced in the above studies. 33,36,39 The high resistance of P. aeruginosa, S. aureus, and P. mirabilis to ampicillin, amoxicillin, and oxacillin may be due to the following factors, like lack of up-to-date knowledge of antimicrobial resistance amongst nurses, physicians, lack of presence of proper antibiogram data, unnecessary, unethical, and irrational uses of antibiotics, self-intake by the patients, push by the pharmacists, irregular intake of antibiotics by the patients. Again, it is known fact that proteus species produces a unique beta-lactamase (cefuroximase) having high activity against cefuroxime, second-generation cephalosporin.…”