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.
ABSTRACT
Background: The use of selective and differential plating media is a simple method for the isolation of Salmonella spp. Recently, there has been a general move toward molecular methods of Salmonella detection and typing
Methods: A total of 1200 different specimens collected from human and animal sources were involved in his study. 600 stool specimens from patients suffering from diarrhea and 600 specimens from gall bladder [bile] of cattle from Al-Diwaniya slaughter house, Iraq were used. Salmonella spp. were isolated and identified using bacterial culturing on selective media and colonies were tested by API 20Eand then serotyping through polyvalent antisera and conformation by Polymerase Chain Reaction [PCR]. PCR was used to detect ompC gene encoding biosynthesis of outer membrane protein C of Salmonella genus
Results: The results revealed that the rate of Salmonella isolates was 0.5% [3/600] from human and 1% [6/600] from animals. The PCR technique revealed that 9 isolates of Salmonella spp. harbored ompC gene. The results of this study revealed that the PCR technique had a high specificity in detection of Salmonella spp., in comparison to culture and biochemical test, Mini API 20 E and serological tests. The present study found no significant differences between human and animal isolates
Conclusion: Detection of ompC gene is a good method for detection of Salmonella species isolated from clinical specimens. It has a high specificity in comparison with other tests, with its advantages of greater speed and effectiveness than conventional detection methods