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Background: Staphylococcus aureus is one of the most frequently isolated microorganisms from burn wounds. Antimicrobial photodynamic therapy (aPDT) is a new strategy that may improve antimicrobial treatment. Method: This study evaluated three meticillin-resistant Staphylococcus aureus (MRSA) and three meticillin-sensitive Staphylococcus aureus (MSSA) clinical isolates, which produced a biofilm with 0.1mg/ml Toluidine Blue O (TBO) (Sigma-Aldrich, Germany) with an energy density of 45J/cm2 and 90J/cm2, for MRSA and MSSA, respectively. The antibiofilm potential of aPDT with TBO was analysed using crystal violet assays and scanning electron microscopy. Results: TBO-aPDT significantly degraded the biofilm formed by MRSA and MSSA clinical isolates (pConclusion: Our results indicated that aPDT is an effective approach to combat bacterial biofilms associated with burn wound infection. aPDT could provide a supplemental to the treatment of wound and tissue infection, and patients with burns may benefit from combined treatments.

Objective: The aim of this study was to investigate the molecular epidemiology and carbapenem resistance mechanisms of Pseudomonas aeruginosa isolated from patients with burns in Azerbaijan, Iran. Method: Pseudomonas aeruginosa was isolated from 38 patients with burns. Disk diffusion and agar dilution methods were used to determine antibiotic susceptibility patterns. The overproduction of AmpC β-lactamase and efflux pumps were detected by phenotypic methods. The presence of carbapenemase-encoding genes was detected by multiplex polymerase chain reaction (PCR). Expression of the OprD gene and MexAB efflux pumps were also evaluated with real-time PCR. Random amplified polymorphic DNA typing (RAPD-PCR) was used for genotyping of carbapenem-resistant Pseudomonas aeruginosa (CRPA). Results: Minimum inhibitory concentration (MIC) assays demonstrated high levels of resistance to all classes of antibiotics except colistin and polymyxin B. The initial screening by carbapenem disks indicated 24 isolates (63.15%) as CRPA. Different mechanisms of carbapenem resistance were observed, including carbapenemase production (8.4%), overexpression of AmpC (25%) and decreased expression of OprD (75%). The overexpression of MexAB efflux pumps was detected in 19 (79.1%) isolates by phenotypic assay or real-time PCR. The resistance to carbapenem was multifactorial in most cases (58.3%). The RAPD genotyping revealed different patterns with nine clusters. Conclusion: According to our results, the prevalence of CRPA is at an alarming level. Our results did not demonstrate an epidemic clone. The most common mechanism of carbapenem resistance was decreased expression of OprD. Therefore, we suggest a reconsideration in the management of CRPA infections of patients in our burn care hospital in Azerbaijan, Iran.

The aim of this study was to investigate the molecular epidemiology and carbapenem resistance mechanisms ofMinimum inhibitory concentration (MIC) assays demonstrated high levels of resistance to all classes of antibiotics except colistin and polymyxin B. The initial screening by carbapenem disks indicated 24 isolates (63.15%) as CRPA. Different mechanisms of carbapenem resistance were observed, including carbapenemase production (8.4%), overexpression of AmpC (25%) and decreased expression ofAccording to our results, the prevalence of CRPA is at an alarming level. Our results did not demonstrate an epidemic clone. The most common mechanism of carbapenem resistance was decreased expression of

Diabetic foot ulcers (DFUs) are a common complication of type-1 and type-2 diabetes. About 10–15% of patients with diabetes develop foot ulcers. A validated foot ulcer classification system that will support the development of treatment strategis is necessary for clinicians managing DFUs. More than 10 classification systems have been described by researchers. Another important aspect of the management of DFUs is the proper identification of causative pathogens that trigger infections. While conventional diagnostic methods, such as swabs, cultures and biopsies are more widely used, novel molecular techniques have been exploring bacterial identification and quantification. Knowledge of the microbial aetiologies in diabetic foot infections, and understanding of antibiotic resistance, is critical for the effective management and treatment of these infected wounds. Initial antibiotic regimens are usually selected empirically. A set of common principles may help avoid selecting either an unnecessarily broad or inappropriately narrow antibiotic treatment regimen. In this review we provide a comprehensive summary and description of classification systems of diabetic foot infections, and a comprehensive discussion of microbiology.

Objective: To investigate the relationship between biofilm formation and antibiotic resistance patterns in meticillin-resistant and meticillin-sensitive Staphylococcus aureus, isolated from burns. Methods: In a cross-sectional study, pus/wound swab samples were obtained from burns. Presence of Staphylococcus aureus was confirmed, and biofilm formation-related icaABCDR and eta, etb genes were detected by polymerase chain reaction. Biofilm formation assay was assessed using the microtiter plate method. Antibiotic resistance was performed using the disk diffusion method and minimum inhibitory concentration. Results: A total of 95 patients with burns were recruited. Of the 95 wounds swabbed, Staphylococcus aureus was identified in 50 (62.5%), and 47 (94%) isolates capable of producing biofilm. Biofilm production levels were classed as ‘strong’ (n=29; 58%), ‘moderate’ (n=11; 22%), ‘weak’ (n=7; 14%) and ‘non-biofilm forming’ (n=3; 6%). There was an almost even split between isolates identified as meticillin-resistant Staphylococcus aureus (MRSA), n=24 (48%), and meticillin-sensitive Staphylococcus aureus (MSSA) n=26 (52%). The prevalence of the icaA, icaB, icaC, icaD and icaR genes among the studied isolates were 96%, 80%, 80%, 96% and 84%, respectively. The prevalence of eta and etb genes in isolates were 84% and 92%, respectively. Conclusion: Biofilm producing isolates of Staphylococcus aureus showed greater multidrug resistance than non-biofilm producers. In our study, a high rate of biofilm formation and antimicrobial drug resistance was seen. Our results highlight the alarming levels of antimicrobial resistance among MRSA strains and important data about the prevalence of eta and etb genes in Staphylococcus aureus strains isolated from burn patients in this study.