In vitro lytic efficacy of bacteriophages against multidrug-resistant pathogenic bacterial species isolated from pyogenic skin infections

Abstract

Bacterial multidrug resistance has worsened the situation by adding to economic burden but also poses a greater risk of patient death. The aim of the study was to characterize the multidrug resistance (MDR) properties of the bacterial isolates from skin infections and then to isolate and evaluate lytic efficacy of bacteriophages against the pathogenic bacteria. Antimicrobial susceptibilities of the isolates (n=84) from pyogenic skin infections against 14 antibiotics was studied using CLSI guidelines. Phylogenetic analyses of the MDR strains from each species was performed. Lytic efficacy of the sewage-derived phages was assessed by spot test. was the most predominant (57, 68%) of the total of 84 isolates. The number of Gram-negative isolates that were resistant to all antibiotics (except amikacin) were significantly higher (P<0.05). On the other hand, significant number of strains were susceptible only to clindamycin and erythromycin (P<0.05). Phylogenetic analysis based on the 16S rRNA gene revealed close relatedness of the strains with MDR strains previously reported. analysis of select MDR strains (n=20) showed that the bacteriophages ΦDMSA-2, ΦDMEC-1 and ΦDMPA-1 against , , and , respectively, showed lytic efficacy against 4 of 5 MDR strains tested from each species. These preliminary, but still important results emphasize the potential of phages as an effective alternative therapy against MDR bacteria. Further, the lytic efficacy of phages underscores the importance of developing need-based and locally isolated bacteriophages as potential antimicrobial therapy alternative to antibiotics.