Central venous catheter associated blood stream infections (CVC-BSIs) in the non-intensive care settings: Epidemiology, microbiology and outcomes.

BACKGROUND: Most studies have examined central venous catheter associated blood stream infections (CVC-BSIs) in Intensive Care Units (ICUs) but information on CVC-BSIs in non-ICU settings is sparse. This study aimed to determine the burden, microbiologic patterns, and associations of CVC-BSIs in non-ICU settings in a tertiary regional centre, University Hospital Geelong (UHG), Victoria, Australia. METHODS: A retrospective study was conducted in the UHG from October 2016 to April 2018. Based on the National Healthcare Safety Network definition, 23 CVC-BSIs occurred in non-ICU settings. Data analysed using SPSS-v25 with a P value < 0.05 was deemed as significant. RESULTS: The incidence rate was 1.2 per 10,000 bed-days. The mean age of patients was 57.22 ± 18 years. 43.5% of patients had Charlson index score of ≥5 and 78% received appropriate empiric antibiotics. The 90-day mortality rate was zero. In total, 26 microorganisms were isolated. Gram-negative bacilli were more common than Gram-positive cocci. The mean catheter duration was 45.22 ± 8.99 days. Hickman lines contributed to 52.2% of BSIs. Within the first two weeks of line insertion, 53.84% of CVC-BSIs occurred with 76.92% of CVC-Gram-negative bacteraemia and 71.4% of BSIs were related to Hickman lines. Also, 69.2% of CVC-BSIs occurred within ≤4 weeks of line insertion including 84.6% of CVC-Gram-negative bacteraemia. CONCLUSION: CVC-BSIs constitute a significant burden on high risk patients in non-ICU settings, with Gram negative bacilli predominating. A prospective surveillance program for all patients with CVC in the non-ICU setting may improve CVC management processes and influence educational measures.

Molecular characterization of intestinal carriage of carbapenem-resistant Enterobacteriaceae among inpatients at two Iranian university hospitals: first report of co-production of bla NDM-7 and bla OXA-48.

Gastrointestinal colonization of carbapenem-resistant Enterobacteriaceae (CRE) could serve as a reservoir for the transmission of these pathogens in the clinical setting. The aim of this study was to investigate the intestinal carriage of CRE and to analyze risk factors for CRE carriage. Rectal swabs were collected from 95 patients at two Iranian university hospitals. CRE screening was performed using selective media (CHROMagar and MacConkey agar). Polymerase chain reaction (PCR) was used to detect carbapenemase-encoding genes. Clonal relatedness was investigated by pulsed-field gel electrophoresis (PFGE). The rate of carriage of CRE in hospitalized patients was 37.9%. Overall, 54 CRE isolates were identified, of which 47 were carbapenemase-producers. All of the 54 CRE were detected using CHROMagar compared with 52 CRE detected using MacConkey agar. Fifteen patients were colonized by multiple CRE isolates. Three significant risk factors for CRE carriage were detected: intensive care unit (ICU) hospitalization, antibiotic exposure, and mechanical ventilation. bla OXA-48 was the most frequent carbapenemase detected, followed by bla NDM-1 and bla NDM-7. Eleven carbapenemase-producing Enterobacteriaceae (CPE) isolates co-harbored bla NDM-1 and bla OXA-48. Also, six CPE isolates co-harbored bla NDM-7 and bla OXA-48. We did not detect bla KPC, bla GES, bla IMP, or bla VIM. PFGE analysis showed that Escherichia coli clones were diverse, while Klebsiella pneumoniae isolates were divided into four clusters. Cluster I was the major clone carrying bla OXA-48 and bla CTX-M-15 genes. In our study, the carriage rate of CRE was high and the emergence of CPE isolates among patients is alarming. The implementation of adequate preventive measures such as active surveillance is urgently needed to control the spread of CPE in the healthcare setting.

In vitro reprotoxicity of carboxyl-functionalised single- and multi-walled carbon nanotubes on human spermatozoa.

Reproductive toxicity of carboxyl-functionalised carbon nanotubes (CNT-COOH), as the most commonly used form of water-soluble CNTs, is not clearly studied. The aim of this study was to investigate in vitro toxicity of carboxylated single-walled and multi-walled CNTs (SWCNT-COOH and MWCNT-COOH) against human spermatozoa. Sperm cells from healthy donors were incubated with 0.1-100 µg/ml of SWCNT-COOH or MWCNT-COOH at 37°C for up to 5 hr. Viability of sperm cells was assessed using MTT test, and sperm motility was evaluated following World Health Organization guideline. Production of reactive oxygen species (ROS) and nitric oxide (NO) in sperm was also assessed. We showed that both MWCNT-COOH and SWCNT-COOH following incubation in vitro with human spermatozoa did not exert negative effect on viability while motility was significantly (p < .05) dropped in a dose-dependent manner. Moreover, there was no significant effect of the type, dose and exposure time of the CNT-COOH on NO production. Exposure of sperm cells to both examined types of CNTs at concentrations as low as 0.1 µg/ml caused a significant increase in ROS levels. In conclusion, carboxylated forms of CNTs seem to be harmful for human spermatozoa. Further studies, especially using in vivo models, are needed to decide about reprotoxicity of carboxylated forms of CNTs.