Molecular Epidemiology of Beta-Lactamases in Ceftazidime-Resistant Pseudomonas aeruginosa Isolates

Pseudomonas aeruginosa is an important opportunistic pathogen that cause mainly nosocomial infections especially in the immunocompromised patients, the elderly and patients with severe burns. The bacterial feature of developing high degree of resistance against several antibiotics leads to increased morbidity and mortality of P.aeruginosa infections. The aims of this study were to investigate the antibiotic susceptibilities of P.aeruginosa strains isolated from hospitalized patients and to determine the presence of resistance enzymes namely PER, GES, KPC, VIM, IMP and OXA. A total of 195 P.aeruginosa strains isolated from different clinical samples (29 sputum, 67 wound, 53 tracheal aspirate, 23 blood, 18 urine, 3 cerebrospinal fluid, 2 pleural fluid) of inpatients (134 male, 61 female) in Afyon Kocatepe University School of Medicine Hospital between 2010-2012, were included in the study. The isolates were identified by conventional methods and automated systems (VITEK 2, BioMerieux, France), and their antibiotic susceptibilities were detected by disk diffusion and E-test methods. Inducible beta-lactamase (IBL), extended-spectrum beta-lactamase (ESBL) and metallo-beta-lactamase (MBL) productions of the isolates were phenotypically investigated by double disk induction, double disk synergy and E-test methods, respectively. The presence of resistance genes encoding PER, GES, KPC, VIM, IMP and OXA enzymes were determined by real-time polymerase chain reaction, and sequence analysis was applied to positive samples. In our study, the antibiotic resistance rates of 195 P.aeruginosa strains were found as follows: ceftazidime 100%, tazobactam/piperacillin 90.8%, aztreonam 60.5%, cefepime 50.2%, imipenem 48.2%, meropenem 47.2%, ofloxacin 47.2%, piperacillin 44.1%, levofloxacin 31.3%, ciprofloxacin 26.2%, gentamicin 11.8%, amikacin 8.7% and tobramycin 6.2%. With the use of phenotypical methods, IBL, ESBL and MBL production rates in the isolates were detected as 89.2% (174/195), 30.7% (60/195) and 26.7% (52/195), respectively. Molecular studies showed that, five strains harboured OXA-10, four OXA-14, four VIM-2, two IMP-1, 26 GES-1 and 87 ABC transporter permease genes, while PER and KPC genes were not detected in any of the isolates. In conclusion, it was considered that the detection of beta-lactamase genes in bacteria and the identification of beta-lactamase types may provide facilities in selection of antibiotics, monitorization of therapy, prevention of resistance development of infection control programs

A Diagnostic Algorithm for the Detection of Clostridium difficile-Associated Diarrhea

Conclusion: Tests targeting C. difficile toxins are frequently applied for the purpose of diagnosing CDI in a clinical setting. However, changes in the temperature and reductant composition of the feces may affect toxin stability, potentially yielding false-negative test results. Therefore, employment of a GDH EIA, which has high sensitivity, as a screening test for the detection of toxigenic strains, may prevent false-negative results, and its adoption as part of a multistep diagnostic algorithm may increase accuracy in the diagnosis of CDIs

Oral colonization and boric acid susceptibility of yeast in boron mineral workers

In this study, we aimed to investigate the effects of boron on in vivo oral yeast colonization in study groups which are exposed to boron dust in different sections of the boron mine. The study was carried out in the boron mining areas of two districts (Eskisehir and Balikesir) of Turkey. We included 184 people working in open quarry and stone milling unit, 144 people working in the factory and 150 people as control group. Specimens were taken from four oral mucosal regions and cultured onto Sabouraud dextrose agar. After incubation for 3-7 days at 30 degrees C, the total number of yeast colonies on the plates was considered the relative intensity of carriage, and the total number of yeast colonies on the plates was considered the relative intensity of oral carriage. The susceptibility of Candida spp. to boric acid was investigated. The frequency of Candida colonization in boron intensive area workers was found significantly higher than automatic factory workers and control groups (p = 0.012), there were no difference between automatic factory workers and control groups in point of Candida colonization (p = 0.749). We observed that oral yeast colonization had increased directly proportional with boron powder exposure in boron mine (p = 0.005). Mean minimum inhibitory concentrations (MICs) of boric acid for Boron intensive area, 0.87-2.0% for automatic factory and 0.83-2.0% for control subjects. We observed that intensive exposure to boron mineral powders was strictly related to oral yeast colonization. Exposure to industrial boron mineral powder may cause important health problems by increasing Candida colonization in oral cavity. It may be useful to do periodical health control in boron mineral workers and population under risk

Association of doripenem resistance with OXA-type carbapenemases in Acinetobacter baumannii isolates

Conclusion: The bla(OXA-23) and bla(OXA-58) gene combinations may confer resistance with a much greater MIC of both meropenem and doripenem. However, the presence of bla(OXA-58) alone was not correlated with doripenem resistance

Association of doripenem resistance with OXA-type carbapenemases in Acinetobacter baumannii isolates

Conclusion: The bla(OXA-23) and bla(OXA-58) gene combinations may confer resistance with a much greater MIC of both meropenem and doripenem. However, the presence of bla(OXA-58) alone was not correlated with doripenem resistance

ROTAVIRUS AND ADENOVIRUS IN CHILDREN WITH ACUTE GASTROENTERITIS AND THE MOLECULAR EPIDEMIOLOGY OF ROTAVIRUS

Conclusion: Regarding the high frequency of rotavirus infection, continuous monitoring is needed in gastroenteritis prevention programs for treatment and to provide information about the occurrence of new rotavirus strains

Detection of the frequency of PER-1 type extended-spectrum beta-lactamase-producing Acinetobacter baumannii clinical isolates in Turkey: a multicenter study

Background/aim: beta-Lactamases are an important resistance mechanism in Acinetobacter baumannii. Pseudomonas extended-resistance (PER-1) type beta-lactamase-producing strains have been reported from various geographic locations; however, PER-1 type beta-lactamases from Turkish hospitals have not been investigated extensively. The aim of this study was to determine the prevalence of PER-1 type beta-lactamases in A. baumannii isolates in various regions of Turkey