Background & Objective:Diabetic foot ulcer (DFU), is one of the most frequent causes for hospitalizations in patients with diabetes. A major problem in the treatment of DFU is the increased-incidence of methicillin-resistant Staphylococcus aureus (MRSA). The aim of this study was to determine the SCCmec types of MRSA isolates and their epidemiology among patients with diabetes.Methods:This study was carried out on 145 diabetic patients with DFUs. The antibiotic susceptibility tests (ASTs) were performed using the disk diffusion method and E-test technique. SCCmec typing was done by multiplex PCR. Moreover, the presence of virulence toxin genes, including pvl and lukED was detected by PCR assay.Results:In 145 samples from which S. aureus was predominantly isolated, 19.48% were MRSA. Analysis of MRSA isolates revealed that the most prevalent SCCmec type was type IV (46.7%) followed by type III (30.0%) and type V (20.0%). One strain (3.3%) was untypeable. The prevalence of pvl and lukED was 56.7% and 100%, respectively.Conclusion:The high prevalence of MRSA in DFUs represents the high levels of antibiotic usage among patients with diabetes. In this study, resistance to other important clinical antibiotics was detected among MRSA isolates. The high proportion of SCCmec type IV and V strains, even in former hospitalized patients, indicates the entrance of these clones to the clinical setting.

No abstract

Aim: We designed a novel approach based on real-time PCR followed by high-resolution melting (HRM) analysis to determine the Staphylococcal cassette chromosome mec (SCCmec) types of methicillin-resistant Staphylococcus aureus  strains, which we compared against the results of conventional multiplex PCR SCCmec typing. Methods: Multiplex PCR (for ccr and mec gene complexes) was carried out as conventional method. The HRM analysis was then designed using standard strains of each SCCmec type. Results: The M-PCR results included types III (33.33%), IV (43.33%) and V (23.33%). HRM analysis was able to distinguish all five types, which were used to set up the protocol with a sensitivity and specificity of 100% compared with the conventional method. Conclusion: This novel method for SCCmec typing has high specificity and sensitivity and can be conducted in a shorter period of time at lower costs.

No abstract

Background: The loop-mediated isothermal amplification (LAMP) method is frequently used for identifying many microorganisms. The present review aimed to evaluate the sensitivity and specificity of LAMP method for detection of food-borne bacteria and to compare these features with those of polymerase chain reaction (PCR), as an alternative molecular diagnostic procedure, and with cultivation method, as the gold standard method. Methods: The literature was searched in electronic databases (PubMed, Scopus, Web of Science, and EMBASE) for recruiting publications within Jan 2000 to Jul 2021. We used the combinations of keywords including foodborne disease, LAMP, PCR, Loop-mediated isothermal amplification, and polymerase chain reaction. Meta-analysis was used to adjust the correlation and heterogeneity between the studies. The efficiency of the methods was presented by negative likelihood ratio, positive likelihood ratio, sensitivity, specificity, and odds ratio using forest plots. A P-value less than 0.05 was considered as statistical significance cut off. The confidence intervals were presented at the 95% interval. Results: Overall, 23 relevant studies were analyzed. The sensitivities of LAMP and PCR methods were estimated to be 96.6% (95% CI: 95.0-97.7) and 95.6% (95%CI: 91.5-97.8), respectively. The specificities of LAMP and PCR were also estimated to be 97.6% (95%CI: 92.6-99.3) and 98.7% (95%CI: 96.5-99.5), respectively. Conclusion: The specificities of LAMP and PCR assays were determined by comparing their results with cultivation method as the gold standard. Overall, the specificity of both PCR and LAMP methods was low for detection of fastidious bacteria. Nevertheless, LAMP and PCR methods have acceptable specificities and sensitivities, and their application in clinical practice necessitates more studies.