Isolation and in vitro evaluation of bacteriophages against MDR-bacterial isolates from septic wound infections

Abstract

Multi-drug resistance has become a major problem for the treatment of pathogenic bacterial infections. The use of bacteriophages is an attractive approach to overcome the problem of drug resistance in several pathogens that cause fatal diseases. Our study aimed to isolate multi drug resistant bacteria from patients with septic wounds and then isolate and apply bacteriophages in vitro as alternative therapeutic agents. Pus samples were aseptically collected from Rajiv Gandhi Institute of Medical Science (RIMS), Kadapa, A.P., and samples were analyzed by gram staining, evaluating morphological characteristics, and biochemical methods. MDR-bacterial strains were collected using the Kirby-Bauer disk diffusion method against a variety of antibiotics. Bacteriophages were collected and tested in vitro for lytic activity against MDR-bacterial isolates. Analysis of the pus swab samples revealed that the most of the isolates detected had Pseudomonas aeruginosa as the predominant bacterium, followed by Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. Our results suggested that gram-negative bacteria were more predominant than gram-positive bacteria in septic wounds; most of these isolates were resistant to ampicillin, amoxicillin, penicillin, vancomycin and tetracycline. All the gram-positive isolates (100%) were multi-drug resistant, whereas 86% of the gram-negative isolates had a drug resistant nature. Further bacteriophages isolated from sewage demonstrated perfect lytic activity against the multi-drug resistant bacteria causing septic wounds. In vitro analysis of the isolated bacteriophages demonstrated perfect lysis against the corresponding MDR-bacteria, and these isolated phages may be promising as a first choice for prophylaxis against wound sepsis, Moreover, phage therapy does not enhance multi-drug resistance in bacteria and could work simultaneously on a wide variety of MDR-bacteria when used in a bacteriophage cocktail. Hence, our results suggest that these bacteriophages could be potential therapeutic options for treating septic wounds caused by P. aeruginosa, S. aureus, K. pneumoniae and E. coli.

Kaptive Web: user-friendly capsule and lipopolysaccharide serotype prediction forKlebsiellagenomes

“…Increasing rates of antimicrobial resistance, particularly against last-line drugs such as carbapenems, has led to a resurgence of interest in phage and monoclonal antibody therapies and vaccinations targeting K. pneumoniae (16)(17)(18)(19)(20)(21)(22)(23)(24)(25). There is particular interest in targeting the globally distributed MDR clones including CG258 (21)(22)(23)26).…”

“…In particular, the emergence and global dissemination of extended-spectrum beta-lactamase (ESBL) and carbapenemase producing (CP) clones is a major concern and has led to the recognition of K. pneumoniae as an urgent public health threat (14,15). With the lack of new antimicrobial therapies, there has been a resurgence of interest in alternative strategies such as phage therapy (16)(17)(18)(19), monoclonal antibody therapy (20)(21)(22)(23) and vaccination (24)(25)(26). Several therapeutic targets have been suggested, and the polysaccharide capsule (K antigen) and lipopolysaccharide (O antigen) are among the most frequent.…”

Evaluation of antimicrobial activity of some plant extracts against antibiotic susceptible and resistant bacterial strains causing wound infection

“…Gram-positive cocci such as Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus spp. and Gram-negative bacilli such as Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Proteus species are the most common pathogenic bacteria isolated from wounds (Pallavali et al,2017).…”

Improving phage titre through examining point of infection

“…Phages were enumerated using the plaque overlay assay. Briefly, a 20ml overnight culture of host bacteria was centrifuged and re-suspended in 3ml fresh media and added to 5ml 0.6% LB bacteriological agar for T4 phage or 0.7% BHI bacteriological agar for Phage K. The mixture was then poured onto a fresh agar plate and the phage were spotted onto the top agar at appropriate dilutions (Bourdin et al, 2014;Pallavali et al, 2017). All shake flask and bioreactor experiments were carried out in triplicate and enumerated by triplicate plaque assays.…”