PP4 -Bacterial identification, their ABST patterns, and associated factors in suspected ear infection patients attending ENT Clinic, Teaching Hospital, Jaffna.

Abstract

Introduction

Ear infections are a common health issue across all ages and a leading cause of preventable hearing loss. Accurate pathogen identification and understanding of associated factors are critical for effective management and prevention. Empirical antibiotic use without sensitivity testing contributes to the development of antimicrobial resistance. However, recent data on bacterial isolates and antibiotic susceptibility in Sri Lanka, particularly Jaffna, remain limited.

Objectives

This study aimed to identify bacterial pathogens, assess their antibiotic susceptibility, and explore factors associated with ear infections among patients attending the ENT clinic at the Teaching Hospital in Jaffna.

Design, setting and methods

An institution-based descriptive cross-sectional study using convenience sampling was conducted from May 31 to July 30, 2024, among patients with ear discharge and clinically suspected bacterial infections, verified by physicians. Bacterial identification and antibiotic susceptibility testing followed the Sri Lanka College of Microbiologists’ Laboratory Manual and CLSI guidelines (26th edition). Socio-demographic, behavioral, and clinical data were collected through interviewer-administered questionnaires with patients and attending physicians. Statistical analysis was performed using Chi-square tests (p < 0.05).

Results

Among 155 patients, 81(52.3%) were male, and 43(27.7%) were pediatric. The culture positivity rate was 89.7%, yielding 143 bacterial pathogens. The most common pathogens were Pseudomonas spp. (48.3%), Enterobacteriaceae (28.7%), Staphylococcus aureus, and Acinetobacter spp. (5.6% each). Pseudomonas spp. showed high susceptibility to Polymyxin B (98.6%) but lower to Ciprofloxacin (79.7%). MRSA was detected in 52.0% (13/25) of Staphylococcus aureus isolates. Multidrug resistance (defined as resistance to ≥3 antibiotic classes) was detected in 22.4% (32/143) of bacterial isolates. Otitis media (OM) accounted for 71.6% of cases, with chronic suppurative OM (57.7%) being the most common, and 59.9% of otitis externa (OE) cases were acute. OM was significantly associated with pediatric and elderly age groups, the use of sharp objects, hearing impairment, and a history of prior infections. OE was associated with the pediatric age group, swimming, water exposure, and passive smoking (p < 0.05).

Conclusions

The high culture positivity with Pseudomonas spp. and the observed antibiotic resistance patterns highlight the need for antimicrobial stewardship programs. The identified associated factors suggest the importance of targeted prevention strategies for better control of ear infections.