Management of Staphylococcus aureus bacteraemia (SAB) in the oncology patient: Further evidence supports prompt removal of central venous catheters and shorter duration of intravenous antimicrobial therapy.

BACKGROUND: Staphylococcus aureus bacteraemia (SAB) is associated with relatively high risk of complications and high levels of mortality. Internationally, SAB management guidelines lack consensus and especially so regarding oncology patients. This is likely a reflection of insufficient randomised control trials (RCT) and the diversity of SAB patient populations. However, there are 2011 guidelines recommending a minimum of 14 days of appropriate IV antibiotic therapy for SAB. OBJECTIVE: We wished to determine whether our practice of shortened duration of intravenous antimicrobial therapy in favour of oral administration proved as effective as recommended guidelines in a mixed oncology patient cohort. METHODS: Retrospective review of patient records that included any SAB episode among oncology patients from January 2002 to December 2015. Medical chart reviews were undertaken to determine patient demographics, clinical management & antimicrobial therapy, duration of stay, presence of a central venous catheter (CVC) and outcome. RESULTS: Our CVC removal rate was just 73% in SAB where CVC was the identified source of infection, with an attributable mortality rate (<4%) far lower than would be expected. Antimicrobial therapy durations were considerably lower (10 days) than current recommendations of 14 days IV therapy. The recurrence rate of 15% was also significantly lower than has been reported previously. CONCLUSIONS: Our observations contribute new insights concerning the management of SAB in oncology patients. Our findings suggest that therapeutic approaches should perhaps remain individualised and reflective of patient characteristics taking into consideration the complex nature of oncology patients.

Hospital effluent: A reservoir for carbapenemase-producing Enterobacterales?

Antimicrobial resistance is a major public health concern. Carbapenemase-producing Enterobacterales (CPE) represent a significant health threat as some strains are resistant to almost all available antibiotics. The aim of this research was to examine hospital effluent and municipal wastewater in an urban area in Ireland for CPE. Samples of hospital effluent (n = 5), municipal wastewater before (n = 5) and after (n = 4) the hospital effluent stream joined the municipal wastewater stream were collected over a nine-week period (May-June 2017). All samples were examined for CPE by direct plating onto Brilliance CRE agar. Isolates were selected for susceptibility testing to 15 antimicrobial agents in accordance with EUCAST criteria. Where relevant, isolates were tested for carbapenemase-encoding genes by real-time PCR. CPE were detected in five samples of hospital effluent, one sample of pre-hospital wastewater and three samples of post-hospital wastewater. Our findings suggest hospital effluent is a major contributor to CPE in municipal wastewater. Monitoring of hospital effluent for CPE could have important applications in detection and risk management of unrecognised dissemination of CPE in both the healthcare setting and the environment.