Changes in antibiotic sensitivity patterns of Gram-negative bacilli in burns

Area of Science:

• Medical Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Gram-negative bacilli are common causes of infections in hospital settings, particularly in burns units.
• Monitoring antibiotic resistance patterns is crucial for effective treatment strategies.

Purpose of the Study:

• To compare antibiotic sensitivity profiles of Gram-negative bacilli from 1969-1971 with those from 1965-1967.
• To identify emerging resistance trends and their potential causes.

Main Methods:

• Sensitivity testing of 1,018 Gram-negative bacilli strains against 12 antibiotics.
• Comparison of resistance patterns between two distinct time periods (1965-1967 and 1969-1971).

Main Results:

• Significant increase in kanamycin resistance observed in Klebsiella aerogenes, Proteus mirabilis, and Escherichia coli.
• Emergence of trimethoprim- and gentamicin-resistant strains.
• Shift in Proteus mirabilis resistance from ampicillin-dissociated to ampicillin-carbenicillin linked resistance.

Conclusions:

• The observed changes in antibiotic resistance are likely associated with the emergence of an R factor.
• This R factor confers resistance to multiple antibiotics including tetracycline, kanamycin, carbenicillin, ampicillin, and cephaloridine.
• The findings highlight the dynamic nature of antimicrobial resistance in clinical settings.