Microbiological isolates of chronic suppurative otitis media at the University Teaching Hospital and Beit Cure Hospital in Lusaka, Zambia

Abstract:

Background: Chronic Suppurative Otitis Media (CSOM) is a common cause of hearing loss and many complications such as meningitis. Many approaches to treatment of CSOM have been unsatisfactory because CSOM microbiological isolates as well as their sensitivity patterns vary from place to place.

Objectives: To determine the pattern of microbiological isolates of CSOM and the demographic characteristics of patients with CSOM at the University Teaching Hospital, (UTH) and Beit Cure Hospital (BCH) in Lusaka, Zambia.

Study design: The study was a hospital-based Cross sectional descriptive study.

Study Setting: The study was conducted at the ENT outpatient clinics of UTH and BCH in Lusaka, Zambia.

Methodology: 100 CSOM patients were included in the study. Quantitative data on the participants’ demographic details and clinical features were obtained using structured questionnaires. The middle ear discharge was aseptically collected using a sterile cotton swab. In the laboratory, samples were inoculated on agar media to isolate microorganisms and antibiotic susceptibility testing was done using Kirby Bauer method as per CLSI guidelines.

Results: Out of the 100 CSOM patients studied, 33(33%) were children below 18yrs and 67(67%) were adults. 59(59%) of the patients had unilateral CSOM while 41 had bilateral CSOM which gave a total of 141 ears that were analyzed. 119(84.4%) had pure cultures, 20(14.2%) had mixed cultures and 2(1.4%) had no growth. Of the 169 microbiological isolates, the most frequent isolates were Proteus mirabilis 49(29.0%), Pseudomonas aeruginosa, 32(18.9%), coagulase negative Staphylococcus 18(10.7%) and klebsiella pneumonie 17(10.1%). High sensitivity rates were revealed to Gentamycin (64-100%), meropenem (68-100%), ceftazidime (85-100%), ceftriaxone (64-80%), and ciprofloxacin (66- 88%). High resistance rates were recorded to Amoxicillin-clavulanate (as high as 100%), ampicillin (as high as 100%), tetracycline (as high as 91.2%) and cotrimoxazole (as high as 100%) and penicillin (as high as 100%).

Conclusion: Proteus mirabilis was the most dominant microbiological isolate followed by Pseudomonas aureginosa. The isolated microorganisms had high susceptibility rates to gentamycin, meropenem, ceftazidime, ceftriaxone and ciprofloxacin. There were high resistance rates to amoxicillin-clavulanate, ampicillin, tetracycline, cotrimoxazole and penicillin.