Investigation of enteropathogenic Escherichia coli and Shiga toxin-producing Escherichia coli associated with hemolytic uremic syndrome in Izmir Province, Turkey

WOS: 000374327500022PubMed ID: 27513249Background/aim: The purpose of this study was to investigate Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic Escherichia coli (EPEC) strains originating from diarrheagenic patients. Materials and methods: A total of 102 patients with diarrhea between October 2012 and January 2013 were enrolled in this study. Multiplex and standard polymerase chain reactions were performed to detect and distinguish STEC and EPEC strains. O serotyping of EPEC was carried out by monovalent antisera. The O and H serotyping of STEC strains was performed at the Refik Saydam Institute, Ankara. Results: A total of 5 (3.42%) strains were identified as STEC, and 3 strains (2.05%) were atypical EPEC. One of the STEC serotypes was O157:H7 carrying VT1, Stx1A, and escv genes. The other STEC strain was identified as O174:H21, which is associated with hemolytic uremic syndrome and consists of VT2 and Stx2A genes. One of the EPEC and three of the STEC serotypes were nontypeable. The serotypes of the atypical EPEC strains were identified as O114 and O26. Conclusion: To the best of our knowledge, this is the first report of O174:H21 from the Izmir region that was shown to be a Shiga toxin-producing non-O157 serotype of STEC

Analyses of Plasmids Harbouring Quinolone Resistance Determinants in Enterobacteriaceae Members

WOS: 000419424400013PubMed ID: 29319519The aim of this study was to explore the plasmid characteristics of eight clinical Enterobacteriaceae strains containing extended broad spectrum beta-lactamases and plasmid-mediated quinolone resistance. Plasmids were transferred by conjugation or transformation and resistance determinants were investigated by PCR. We showed that at least one plasmid harbouring qnrB or qnrS determinant was transferred by conjugation in five isolates. QepA determinant was confirmed to be on a non-conjugative plasmid. We found at least one beta-lactamase gene in seven of the eight clinical isolates having plasmid-mediated quinolone resistance, which indicated that these two resistance determinants were mostly on the same conjugative plasmids.Ege University Scientific Research ProjectEge University [12ECZ012]This study was supported as an Ege University Scientific Research Project (12ECZ012). The authors would like to thank to Prof. George A. Jacoby, Prof. Kunikazu Yamane, Prof. Osman Birol Ozgumus and Prof. Hasan Nazik for kindly providing the positive control strains and plasmids. The authors would like to thank to Prof. Zeki Topcu, Assoc. Prof. Sevil Zencir, PhD Hasan Akbaba and Ege University Faculty of Pharmacy Pharmaceutical Sciences and Research Center (FABAL)

Comparison of Culture-Positive and -Negative Microbial Keratitis

Objectives: To evaluate and compare the risk factors, presenting features, and outcomes of patients with culture-positive and culture-negative microbial keratitis (MK) who presented to a tertiary referral center. Materials and Methods: We conducted a retrospective review of the medical records of 314 patients who were diagnosed with MK in our clinic between 2012 and 2019. Results: Among 314 patients, 142 had positive cultures (45.2%). The mean ages of the culture-positive and-negative patients at the time of diagnosis were 51.39 +/- 21.31 (range, 14-90) years and 56.68 +/- 21.34 (7-94) years, respectively (p=0.028). The mean best corrected visual acuity (BCVA) of the culture-positive and-negative patients were1.74 +/- 1.25 (0-3.1) LogMAR and 1.91 +/- 1.23 (0-3.1) LogMAR prior to treatment and increased to 1.21 +/- 1.30 (0-3.1) LogMAR and 1.27 +/- 1.29 (0-3.1) LogMAR at last visit, respectively. There was no statistically significant difference between culture-positive and-negative patients' BCVA levels at presentation or last visit. Ninety-two patients (64.7%) were infected with bacteria and 50 patients (35.2%) with fungi. The most common pathogen was Pseudomonas aeruginosa (18.3%), followed by Streptococcus pneumoniae (11.2%) and Fusarium spp. (11.2%). Keratitis foci were either centrally or paracentrally located in 105 eyes (73.9%) of culture-positive patients and 149 eyes (86.6%) of culture-negative patients. Multiple foci were present mostly in culture-positive patients (p=0.001). There was no significant difference between the culture-positive and-negative groups in terms of hypopyon presence (p=0.364). The proportion of contact lens (CL) wearers was 33% (n=47) among culture-positive MK patients and 13.3% (n=23) among culture-negative MK patients, respectively (p<0.001). Culture positivity was found to be significantly higher in keratitis associated with CL use (p=0.0001). Conclusion: Microbiological analysis and culture evaluation are important steps in order to manage proper treatment in microbial keratitis. Prognosis mostly depends on the infectivity of the microbiological agent

Silencing acpP gene via antisense oligonucleotide-niosome complex in clinical Pseudomonas aeruginosa isolates

Pseudomonas aeruginosa, an opportunistic Gram-negative pathogen, is one of the major causes of nosocomial infections. In addition to its physiological adaptation capacity, it can develop resistance to disinfectants and antibiotics through various mechanisms. Recently, new eradication methods are gaining attention. Therefore, in this study, an LNA-2'-O-methyl hybrid antisense oligonucleotide targeting the acyl carrier protein P (acpP) gene was introduced into P. aeruginosa isolates. The design was determined through sequence analysis and prediction of the secondary structure of mRNA by software. Niosomes were used for enhancing cellular uptake. The control of the binding and transfection ability of the sequence was determined fluorometrically by labeling with 6-Fam. The effects were determined with broth microdilution method and qPCR studies. Eight different formulations were prepared. Among these, one formulation has shown to have ASO complexation ability whose composition was 312 mu l Span 80 + 69.5 mg Cholesterol+ 36.4 mg CTAB+1 ml Chloroform and 5 ml dH(2)O. Thus this formulation was determined as the delivery system for the next stages. Significant gene inhibition was detected at the six isolates. Results of this study suggested that niosomes can be used as a delivery system for cellular uptake of ASO and could eliminate bacterial growth. (C) 2021 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.Scientific and Technological Research Council of Turkey [215S824]The Scientific and Technological Research Council of Turkey by Grant No. 215S824 financially supported this study

Serotype distribution of Streptococcus pneumoniae and pneumococcal vaccine coverage in adults in Turkey between 2015 and 2018

AbstractObjective To evaluate the serotype distribution and antibiotic resistance in pneumococcal infections in adults and to provide a perspective regarding serotype coverage of both current and future pneumococcal vaccines.Patients and methods This passive surveillance study was conducted with the Streptococcus pneumoniae strains isolated from the specimens of patients with pneumonia (materials isolated from bronchoalveolar lavage), bacteraemia, meningitis, pleuritis and peritonitis between 2015 and 2018. Serogrouping and serotyping were performed by latex particle agglutination and by conventional Quellung reaction using commercial type-specific antisera, respectively. The strains were analysed for penicillin, cefotaxime, erythromycin and moxifloxacin susceptibilities by E-test.Results In the whole study group (410 samples from adults aged ≥18 years), the most frequent serotypes were 3 (14.1%), 19 F (12%) and 1 (9.3%). The vaccine coverage for PCV13, PCV15, PCV20 and PPV23 was 63.9%, 66.6%, 74.1% and 75.9%, respectively, in all isolates. Penicillin non-susceptibility in invasive pneumococcal disease (IPD) was 70.8% and 57.1% in the patients aged <65 and ≥65 years, respectively. About 21.1% and 4.3% of the patients with and without IPD had cefotaxime resistance. Non-susceptibility to erythromycin and moxifloxacin was 38.2% and 1.2%, respectively.Conclusions The results revealed that novel PCV vaccines may provide improved coverage as compared with the currently available vaccine, PCV13. The significant antibiotic resistance rates imply the need to extend the serotype coverage of the vaccines. Continuing the surveillance in pneumococcal diseases is critical to explore the serotype distribution and incidence changes of IPD cases in the population and to inform policy makers to make necessary improvements in the national immunization programmes.Key messagesThis multicentre study demonstrated the most recent serotype distribution and antibiotic resistance in adult population in Turkey.Shifting from PCV13 to novel conjugated vaccines will significantly increase the coverage.Continuing the surveillance in pneumococcal diseases is critical to explore the serotype distribution changes and the incidence of cases with invasive pneumococcal disease in the population