Molecular detection and antimicrobial resistance of Clostridium perfringens isolated from diabetic patients and bullet wounds

ABSTRACT

Clostridium perfringens is a major cause of gas gangrene. The morbidity of C. perfringens is connected with producing toxins. This cross-sectional study was designed to isolate, genetically diagnose, and study the antibiotic susceptibility patterns of C. perfringens isolated from clinical samples. Different wound swabs (from diabetic patients, cellulitis, and bullet wounds) were taken from 140 patients. For isolation of anaerobic bacteria, samples (in thioglycolate broth) were immediately incubated anaerobically then identified according to the cultural properties and biochemical tests. DNA was extracted from all specimens. Polymerase chain reaction was applied for detection of 16SrRNA and internal transcribed spacer (ITS) genes of C. perfringens. The susceptibility of bacterial isolates to different antibiotics was determined using Vitek 2 system and disk diffusion test. Out of 140 clinical samples collected during this study, 3 (2.14%) C. perfringens isolates were recovered of which 2 isolates (1.43%) obtained from diabetic patients and one (0.71%) from bullet wounds. Results also showed that only 7 isolates (5%) were detected by a molecular method using specific primers 16S rRNA and ITS genes of C. perfringens. Results of antibiotic susceptibility testing showed that all isolates were highly susceptible to penicillins and β-lactamase inhibitors, metronidazole, and aminoglycosides. On the other hand, all isolates were highly resistant to tetracycline, levofloxacin, and erythromycin. The susceptibility patterns of C. perfringens isolates showed that all isolates were multidrug resistance. Using the amplification of ITS gene increases specificity and sensitivity (by reducing non-specific annealing and primer dimer formation) which increases the probability of detection of suspected C. perfringens isolates.