Antibiotic susceptibility pattern of bacterial isolates from microbial keratitis in North and Central India: A multi centric study

PURPOSE: This study was conducted to examine microbiological profile with their antibiotic sensitivity in cases of bacterial keratitis in north and central India to ensure appropriate use of antibiotics. METHODS: The microbiology laboratory records of 228 patients with culture-proven bacterial keratitis from 1(st) January to 31(st) December 2019 were analyzed. Cultured bacterial isolates were subjected to antimicrobial susceptibility testing to antibiotics commonly used in the treatment of corneal ulcer. Chi-squared or Fisher’s exact test were applied to check the significance of difference between the susceptibility levels of antibiotics. RESULTS: The prevalence of Staphylococcus aureus and Pseudomonas aeruginosa–induced keratitis was higher in northern India, whereas that by Streptococcus pneumoniae was more prevalent in central India. In central India, 100% of S. pneumoniae isolates were found to be sensitive to ceftriaxone compared to 79% in northern India (P = 0.017). In comparison to 67% of isolates from north India, 15% of S. aureus isolates from central India were found to be sensitive to ofloxacin (P = 0.009). Similarly, 23% of isolates from central India were found sensitive to amikacin compared to 65% of isolates from north India (P = 0.012). P. aeruginosa isolates from central India were found to be sensitive to ceftazidime in 63% of cases compared to 21% of isolates from north India (P = 0.034). CONCLUSION: Prevalence of bacteria and their susceptibility to antibiotics are not uniform across geography. Vancomycin remained the most effective drug in all gram-positive coccal infections. S. aureus susceptibility to amikacin was significantly greater in north India. P. aeruginosa showed less susceptibility as compared to previous reports.