Prevalence, Sensitivity Profile and Resistance of Gram-Positive Bacteria in Wounds to Conventional Antibiotics

Aim: The prevalence, sensitivity profile and resistance of Gram-positive bacteria in wounds to commercial antibiotics were ascertained in this study.

Place and duration of study: University of Medical Sciences Teaching Hospital, Akure, Nigeria, between January and June 2019.

Methodology: Wound swabs sample collection, isolation of bacteria, identification of Gram-positive bacteria isolates and antibiotics sensitivity testing of isolated bacteria were determined employing standard protocols.

Result: Three Gram-positive bacteria were isolated and presumptively identified to be S. aureus, S. epidermidis and S. pyogenes. S. aureus had the highest prevalence of 53% followed by S. epidermidis with 42% and S. pyogenes accounting for the least occurrence of 5%. Ninety percent (90%) of ten S. aureus strains were resistant to ciprofloxacin while only 10% had intermediate activity. The least resistance of S. aureus strains was against pefloxacin (40%), while to streptomycin, 87.5% of eight S. epidermidis strains were resistant and 12.5% had intermediate sensitivity. Susceptibility was observed in S. epidermidis against pefloxacin (12.5%) while 50% had intermediate sensitivity and 37.5% were resistant. The highest zone of inhibition of S. epidermidis was observed in strain 7 against pefloxacin (16.00±1.00 mm) and in S. aureus by strain 5 against pefloxacin (16.50±2.50 mm).

Conclusion: Pefloxacin-sensitive Staphylococcus and Streptococcus species from wound swabs could become resistant overtime and this calls for incessant vigilance on Gram-positive wound bacteria antibiotic-susceptibility appraisal particularly in an antibiotics-abuse setting.