High prevalence of plasmid-mediated quinolone resistance in escherichia coli strains producing extended-spectrum beta-lactamases isolated from faeces and urine of pregnant women with acute cystitis.

BACKGROUND: Escherichia coli is the most common etiological agent of urinary tract infections (UTIs). Meanwhile, plasmid-mediated quinolone resistance (PMQR) is reported in E. coli isolates producing extended-spectrum ß-lactamases (ESBLs). Furthermore, the reservoirs and mechanisms of acquisition of uropathogenic Escherichia coli (UPEC) strains are poorly understood. On the other hand, UTIs are common in pregnant women and the treatment challenge is alarming. METHODS AND RESULTS: In the present study, 54 pregnant women with acute cystitis were included. A total of 108 E. coli isolates, 54 isolates from UTI and 54 isolates from faeces of pregnant women (same host) were collected. In the antimicrobial susceptibility test, the highest rate of antibiotic resistance was to nalidixic acid (77%, 83/108) and the lowest rate was to imipenem (9%, 10/108). Among the isolates, 44% (48/108) were ESBLs producers. A high frequency of PMQR genes was observed in the isolates. The frequency of PMQR genes qnrS, qnrB, aac(6')-Ib-cr, and qnrA was 58% (63/108), 21% (23/108), 9% (10/108), and 4% (4/108), respectively. Meanwhile, PMQR genes were not detected in 24% (20/85) of isolates resistant to nalidixic acid and/or fluoroquinolone, indicating that other mechanisms, i.e. chromosomal mutations, are involved in resistance to quinolones, which were not detected in the present study. In ESBL-producing isolates, the frequency of PMQR genes was higher than that of non-ESBL-producing isolates (81% vs. 53%). Meanwhile, UTI and faeces isolates mainly belonged to phylogenetic group B2 (36/54, 67% and 25/54, 46%, respectively) compared to other phylogenetic groups. In addition, virulence factors and multidrug-resistant (MDR) were mainly associated with phylogenetic group B2. However, predominant clones in faeces were not found in UTIs. Rep-PCR revealed the presence of 85 clones in patients. Among the clones, 40 clones were detected only in faeces (faeces-only), 35 clones only in UTI (UTI-only) and 10 clones in both faeces and UTI (faeces-UTI). We found that out of 10 faeces-UTI clones, 5 clones were present in the host's faeces flora. CONCLUSION: This study revealed a high rate of resistance to the quinolone nalidixic acid and a widespread distribution of PMQR genes in MDR E. coli strains producing ESBLs. The strains represented virulence factors and phylogenetic group B2 are closely associated with abundance in UTI and faeces. However, the predominant clones in faeces were not found in UTIs and it is possible that rep-PCR is not sufficiently discriminating clones.

Bacterial assessment of food handlers in Sari City, Mazandaran Province, north of Iran.

Food handlers with poor personal hygiene could be potential sources of infection due to pathogenic bacteria. This study was designed to determine the prevalence of bacterial infestation among the food handlers attending the public health center laboratory in Sari, northern Iran for annual check-up. This study was performed from September 2013 to August 2014. Stool samples, fingernail specimens of both hands and nasal swabs were collected from 220 male and female food handlers of different jobs, aged between 17-65 years. The samples were cultured on bacteriological culture media and bacterial species were identified following standard procedures. A structured questionnaire was used to record sociodemographic and behavioral data analysis of the food handlers. Of the total 220 subjects examined, 62.2% showed positive culture for different bacterial species from their fingernail contents, 65.4% were found to be harboring Staphylococcus aureus in their nostrils and 0.9% tested positive for Shigella boydii from stool samples. Staphylococcus aureus was the predominant bacteria isolated from fingernail specimens (46%), followed by Escherichia coli (29.2%), Coliforms (18.2%) and Pseudomonas aeruginosa (6.6%). This study showed a statistically significant difference in the rate of bacterial infestation between different occupational categories (p=0.04). Butchers showed the highest prevalence of bacteria (86.6%) in their fingernail contents, followed by fast food workers (76.5%), bakers (73.5%), chicken store workers (73%), school cafeterias staff (53.3%), restaurant workers (46.9%) and fruit/vegetables sellers (42.5%). The highest rate of nasal carrier for Staphylococcus aureus was observed among chicken store workers 14/17(20.8%). These findings indicate the need for intensive training/retraining and health education of all food service employees and strengthening the existing screening methods to control the problem of bacterial infestation in food handlers.

Distribution of bla(OXA-23), ISAba , Aminoglycosides resistant genes among burned & ICU patients in Tehran and Sari, Iran.

BACKGROUND: Multidrug resistant strains of Acinetobacter baumannii (MDR-AB) have emerged as alarming nosocomial pathogens among patients admitted to Intensive Care Unit and burned patients. The aim of this study was to determine the susceptibility of A. baumannii isolates, the carbapenems resistance patterns bla(OXA-23) and also ISAba elements of A. baumannii isolates among burned and ICU patients in Tehran and Sari, Iran. METHODS: In this study, 100 A. baumannii isolates from burned and ICU patients in Tehran and Sari (Iran) during 2013 were tested for determination of antimicrobials susceptibility by the disc-diffusion method on Mueller Hinton agar recommended by the guidelines of Clinical and Laboratory Standards Institute (CLSI), and frequency bla(OXA-23) carbapenemase genes, and insertion elements ISAba genes were studied by PCR method. RESULTS: The highest rates of susceptibility were observed with Colistin (88.7%), Tigecycline (82.2%), Imipenem (67%) and ISAba (32.2%). The extensively drug-resistance and pan drug-resistance were observed in 37.1% and 8.1% isolates, respectively. Results indicated among isolates resistant to Aminoglycoside and Carbapenem, the highest resistance was observed to Streptomycin (90%) ' and the most sensitivity was to Imipenem (67%). CONCLUSIONS: This is the most study that attempted to detect Acinetobacter baumanii the insertion elements ISAba , bla(OXA-23) and aminoglycosides resistance in MDR-AB isolates from burned and ICU patients in Iran. In a timely manner, antimicrobial resistance surveillance and strict infection control strategies are still lacking in burn ward and ICU in Iran, despite the alarming emergence of MDR-AB strains, particularly among those isolates that are not susceptible to Colistin. The results of this study are consistent with a recent report in which a number of combinations exhibited potent activity against Multidrug resistant strains of A. baumannii (MDR-AB).