CHARACTERIZATION OF STAPHYLOCOCCUS AUREUS ISOLATED FROM BURN WOUND; STRONG ANTIBACTERIAL ACTIVITY OF PHAGE COCKTAIL AGAINST VANCOMYCIN INTERMEDIATE-RESISTANT STAPHYLOCOCCUS AUREUS

Abstract

A universal problem is about spread of Staphylococcus aureus infections in burn patients. The present study aimed to learn about the molecular characteristics and the resistance pattern of S. aureus strains isolated from burn patients. In this cross-sectional study, we investigated 100 unique S. aureus isolated from burn patients by antimicrobial activity and biofilm formation and evaluated the effect of Complex Pyobacteriophage, a commercial bacteriophage cocktail, against the isolates mentioned above. Methicillin-resistant Staphylococcus aureus (MRSA) comprised 76%, and methicillin-susceptible Staphylococcus aureus (MSSA) comprised 24% of 100 S. aureus strains. The resistance rate among MRSA isolates was higher than compared of MSSA. Mupirocin resistance was found in 30% of isolates, with 28 (93.3%) and 2 (6.7%) strains of MRSA and MSSA, respectively, found. Vancomycin intermediate resistance in S. aureus (VISA) was 13% of MRSA strains. Two isolates were confirmed as vancomycin-resistant S. aureus (VRSA) strains and carried vanA. 31 and 62% of the total isolates showed inducible and constitutive resistance phenotypes. The rate of inducible and constitutive clindamycin resistance among MRSA strains was higher than MSSA strains. Biofilm production was detected in 66% of isolates. Strong, moderate, and weak producers accounted for 25%, 17%, and 24% of isolates. Phage analysis showed that 81% were susceptible to the phage cocktail, and only 19% were resistant to the phage cocktail. Our data indicated that VISA strains prevalence in the burn unit was mainly from S. aureus infections. Present work recommended that vancomycin treatment be closely monitored to prevent the spread of VISA and VRSA strains. Observations also highlighted the role of bacteriophage cocktails in eradicating S. aureus-related infections.