Study and identify integrons class I, II III, Salmonella typhimurium isolated from clinical samples of Tehran Medical Centers

Background: Salmonella, as an aerobic and facultative anaerobe bacillary gram-negative bacterium, is pathogen for humans and animals. This bacterium dominates the vertebral gastrointestinal tract, depending on the serotype and host conditions and factors, causes diseases with various symptoms and complications. Today, the development of multiple antibiotic resistance in this bacterium is a major barrier to public health. Integrons can play an important role in creating and expanding this resistance. The aim of this study was to investigate the presence of class I, 2 and 3 integrons in Salmonella typhimurium isolated of clinical samples by Multiplex PCR

Materials and methods: In this study, 60 isolates of Salmonella typhimurium were collected from Tehran Hospitals and confirmed by biochemical and culture tests. Multiplex-PCR assay was performed to identify int1, int2 and int3 integrons genes

Results: Of the 60 strains of Salmonella typhimurium, PCR assays detected 85 percent integron class 1, 45 percent integron class 2, and 70 percent integron class III

Conclusion: The results of this study showed high incontinence in Salmonella typhimurium strains isolated from clinical cases. Identifying these genes can be an important strategy in identifying and responding to antibiotic resistance, since the presence of infrared cells is an indicator of the development and spread of antibiotic resistance

[Detection of cmlA/tetR, bla PSE-1, bla TEM and sip B in the Salmonella strains by Multiplex-PCR method and their antibiotic resistance pattern]

Background: Gastroenteritis due to Salmonella is common in human and considered as a global dilemma of public health. This study was done to determine cmlA/tetR, bla PSE-1, bla TEM and sip B in the Salmonella strains by Multiplex-PCR method and their antibiotic susceptibility profile

Materials and methods: In this cross-sectional study, 163 clinical samples were obtained from patients admitted to Hazrat-e Rasool General Hospital. The antibiotic susceptibility test was determined using the disk diffusion method agreeing with CLS1 guideline. Then, M-PCR was achieved for determination of these target genes by the specific oligonucleotides primers

Results: Of 163 collected samples, 48[29.4%] Salmonella spp., were obtained, which 25[52.1%] were S. enteritidis, 14[29.2%] S. typhimurium and 9[18.7%] S. infantis. Antibiotic resistance analysis showed that the highest resistance rate were related to tetracycline [n: 27, 56.2%] and then streptomycin and chloramphenicol [n: 15, 31.2%]. All isolates [n: 48, 100%] were susceptible to imipenem, amikacin, gentamycin and trimethoprim/sulfamethoxazole. The MPCR results revealed that 62.5% and 16.6% of Salmonella spp., isolates carried cml/tetR and sipB genes, respectively

Conclusion: According to our results, detection and genotyping of virulence genes and comparison with global ranging is a basic requirement in the control and prevention of salmonellosis in industrial purposes

[Evaluation of ESBL genes of blaTEM, blaSHV, blaoxa and aminoglycoside gene of aadA in Escherichia coli strains isolated in Tehran and determination of antimicrobial resistance]

Background: Nowadays, the widespread use of broad-spectrum beta-lactam antibiotics has increased antibiotic resistance around the world. The aim of this study was to assess and identify genes blaTEM, blaSHV, blaoxa and blaaada in clinical isolates E.coli by Multiplex- PCR methods

Materials and methods: In this descriptive study, 150 stool samples from different treatment centers in Tehran were randomly gathered; and biochemical tests detected 55 E. coli. Antimicrobial susceptibility testing was performed by disk diffusion method according to CLSI. Multiple PCR assay was used to identify the genes beta-lactamase. Data were analyzed by descriptive statistical analysis using SPSS version 19

Results: Highest sensitivity was observed to cefpodoxime and trimethoprim [90.9% and 58.1% respectively] and the maximum resistance was reported to imipenem and ciprofloxacin [76.3% and 100% respectively]. PCR results showed bla oxa gene in 40 isolates [72.7%], aadA gene in 15 samples [27.2%] and concurrent blaoxa/ aadA genes in 12 isloates [21.8%]. blaTEM and blaSHV genes were not identified in samples

Conclusion: Antibiotic resistance to E.coli in children with diarrhea is indicated the indiscriminate use of antibiotics. Monitoring and control of drug-resistant intestinal bacteria play a major role in preventing the creation of resistant strains