Background:Mycobacterium tuberculosis genotyping can effectively improve tuberculosis (TB) control programs by controlling disease transmission. Pulsed field gel electrophoresis (PFGE) is a particularly powerful tool for determination of clonal identity of bacteria providing information for understanding and controlling the spread of disease.Objectives:The aim of present study was to investigate the genetic diversity of M. tuberculosis strains in Khuzestan province by the PFGE technique.Patients and Methods:In total, 80 M. tuberculosis positive cultures were obtained from tuberculosis patients. PFGE was performed on 60 PCR-confirmed isolates by using DraI and XbaI restriction enzymes according to standard protocols. Plugs containing digested DNA were then loaded on agarose gels and run using contour-clamped homogenous electric fields.Results:Fifty distinct DNA banding patterns were obtained by digestion of DNA with DraI and 38 DNA banding patterns by digestion with XbaI restriction enzymes. The patterns comprised of 17 different clusters in which cluster I was the major one, containing six strains. Three clusters contained three strains each and the 13 remaining clusters comprised of two strains each. Digestion with DraI yielded 15-20 DNA fragments with 50-485 kb size, while digestion by XbaI produced DNA fragments with a size smaller than 50-242 kb.Conclusions:Despite the ability of PFGE for study of genetic diversity of many mycobacterial species and it being considered as a robust and useful tool, in this study we only found a 15% epidemiological relationship amongst the isolates. Thus, for higher discrimination of genotypic clusters among M. tuberculosis clinical isolates, the application of more sophisticated complementary techniques is required.

Due to the emergence of antibiotic resistance in Acinetobacter baumannii which is one of the important causes of nosocomial infections, many problems have been raised in the successful treatment of patients with the subsequent mortality. So, the present study was performed to evaluate the antibacterial effect of Actinidine dehydrochloride, Actinisept, and Benzalkanium chloride against Acinetobacter baumannii strains isolated from clinical samples and to determine the genetic diversity of strains by RAPD-PCR. A total of 119 non-duplicate, suspected Acinetobacter baumannii isolates were collected and confirmed by conventional culture and biochemical tests and PCR technique. Susceptibility of the isolates to antibiotics was evaluated by standard Antibiotic susceptibility testing (AST). For antiseptics Octenidine dihydrochloride (OCT), Actinisept, and Benzalkonium chloride (BZK), Minimal inhibitory concentration (MIC) was assessed. The prevalence of Qac E and Qac delta E genes related to antiseptics was estimated by PCR. Finally, genetic diversity of strains was determined by RAPD-PCR. All 119 suspected isolates were confirmed as Acinetobacter baumannii using conventional tests and PCR. The isolates were mostly originated from blood samples. In AST, the lowest resistance was seen for ciprofloxacin and gentamicin. The MIC values were reported as OCT (15.26 µg) and BZK (640 µg). The antiseptic genes of qacE and qac ΔE1 were found to be present in 56 (47.05%) and 59 (49.57%) of isolates respectively. RAPD typing method revealed great diversity among A. baumannii isolates, with 37 clusters in isolates from ICU, of which 32 isolates were single and 5 were multiple. In conclusion, considering the increase of resistance to antiseptics, it is of importance to monitor the susceptibility of A. baumannii to antiseptics and to promote antiseptic stewardship in hospitals. Furthermore, in this study great diversity among A. baumannii was observed making it difficult to properly carry out infection control policies. analysis of RAPD-PCR typing results, and we found 37 clusters, among them 32 isolates were single and 5 were multiple. So, the method generated 37 RAPD type which shows great diversity among 57 out of 62 A. baumannii isolates at 80% cutoff.