Microbiological profile of chronic suppurative otitis media among patients attending outpatient clinics at alexandria main university hospital, Egypt

Abstract

Background: Chronic suppurative otitis media (CSOM) is a major public health problem in Egypt and one of the most common diseases of the ear for all age groups. The prevalence and antibiogram of microorganisms associated with CSOM have been reported to vary with time and geographical area probably due to indiscriminate use of antibiotics. Prompt appropriate antimicrobial therapy can effectively reverse the disease process, thereby preventing long term sequels. Hence, the periodic update of the prevalence and antibiogram of the etiological agents for CSOM would be helpful in management of patients. Methods and materials: A cross-sectional study was conducted on 143 patients with active CSOM attending the outpatient clinics of the Otorhinolaryngology Department at Alexandria Main University Hospital (AMUH) over a period of one year from September 2017 to August 2018. Ear discharge samples were aseptically collected using sterile cotton swabs and analyzed by the standard microbiological procedures. Data were analyzed using SPSS (Statistical Package for Social Science) version 21 software. Results: Pathogens were isolated from 95.00% of samples with a total of 153 isolates. Pseudomonas aeruginosa (24.83%), Staphylococcus aureus (S. aureus) (22.22%) and Proteus mirabilis and coagulase-negative staphylococci (13.07% each) were the dominant bacterial isolates. Anaerobes represented only 1.31% of the bacterial isolates and comprised of Peptostreptococcus and Bacteroides spp. Fungi were isolated from 14.38% of samples and comprised of Aspergillus flavus (45.83%), Aspergillus niger (25.00%), Candida albicans and non-albicans Candida (12.50% each) and Penicillium spp. (4.17%). Half of S. aureus isolates (50.00%) were methicillin-resistant S. aureus (MRSA), while 3 (8.82%) were vancomycin-resistant S. aureus (VRSA). Seventy-one (46.41%) aerobic bacterial isolates were multi-drug resistant (MDR), while 6 (3.92%) were pan-drug resistant (PDR). Only 50.33% of aerobic bacterial isolates were sensitive to ciprofloxacin which is the standard antibiotic prescribed by physicians at the outpatient clinics at AMUH. Conclusion: The most common causes of the studied CSOM infections were Pseudomonas aeruginosa and S. aureus.Treatment of CSOM should be based on results of culture and antibiotic susceptibility tests instead of empirical treatment to avoid emergence of MDR and PDR bacteria. Fungal culture should be considered in CSOM, since fungal infection can occur without specific signs and symptoms.