A STUDY ON BIOFILM-MEDIATED MECHANISMS CONTRIBUTING TO MULTIDRUG RESISTANCE IN BACTERIAL PATHOGENS ISOLATED FROM EXTERNAL OCULAR INFECTIONS IN CENTRAL INDIA
Main Article Content
Keywords
Biofilm formation, Multidrug resistance (MDR), Ocular pathogens, External ocular infections
Abstract
Background: External ocular infections are a significant health concern, particularly in pediatric populations and in patients with underlying comorbidities. The increasing prevalence of multidrug-resistant (MDR) bacteria and biofilm-producing pathogens further complicates treatment.
Objective: To identify the bacterial pathogens responsible for external ocular infections, assess their antibiotic susceptibility profiles, and explore the relationship between multidrug resistance and biofilm formation.
Methods: A total of 319 patients (mean age 21 years) presenting with external ocular infections were enrolled. Bacterial culture and antibiotic susceptibility testing were performed using standard microbiological techniques and CLSI 2021 guidelines. Biofilm formation was assessed, and statistical analyses including multivariate logistic regression were conducted.
Results: Positive bacterial growth was obtained from 147 (46.1%) ocular specimens. Gram-positive bacteria accounted for 65.3% of isolates, with coagulase-negative staphylococci (CoNS, 27.9%) and Staphylococcus aureus (19.7%) being the most prevalent. Among Gram-negative bacteria (34.7%), Pseudomonas aeruginosa (10.8%) and Klebsiella pneumoniae (9.1%) predominated. Conjunctivitis was the most common clinical diagnosis (51.7%). Significant associations were found between bacterial infection and comorbid diabetes mellitus (AOR = 0.09, p = 0.002) and previous hospitalization (AOR = 0.10, p = 0.001). High levels of resistance were observed to penicillin (82.7%) and ampicillin (78.3%) among Gram-positive isolates, while Gram-negative bacteria showed resistance to ampicillin (90%) and tetracycline (73.5%). Ciprofloxacin and gentamicin remained effective against most isolates. MDR was observed in 68.7% of isolates, and 48.4% of MDR strains were strong biofilm producers, indicating a statistically significant correlation (p < 0.05).
Conclusion: The high prevalence of MDR and biofilm-producing bacteria in ocular infections underscores the need for ongoing surveillance and prudent antibiotic use. Fluoroquinolones and carbapenems remain effective, but rising resistance trends necessitate timely microbiological evaluation and targeted therapy.
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Mohit Kumar
Demonstrator Department of Microbiology, School of Health Sciences, CSJMU
Kanpur (U.P.)
Ruchi Gupta
Assistant professor, Department of Microbiology, GSVM Medical College Kanpur (U.P.)
Soumya Singh
Assistant Professor, Department of Microbiology, ASMC Sultanpur (U.P.)