Reduced VRE and MRSA colonisation and infection following sustained reduction in broad spectrum antibiotic use in a large tertiary hospital

Abstract

T he international shortage of piperacillin/tazobactam (PT) in 2017 prompted its replacement by intravenous amoxicillin/clavulanate (IVAC). 1 Two studies have examined the effect of broad spectrum antibiotic usage on the epidemiology of vancomycin-resistant Enterococcus (VRE) in hospitals. An interrupted time series study found that VRE prevalence declined after partial replacement of cephalosporins, vancomycin and clindamycin by ampicillin/sulbactam and, to a lesser extent, PT. 2 In another study, a switch from ceftazidime to PT for febrile neutropenia was associated with reduced VRE acquisition in a haematology unit. 3 We examined the impact of the PT shortage on VRE and methicillin-resistant Staphylococcus aureus (MRSA) acquisitions at the John Hunter Hospital (Newcastle), where there has been a sustained outbreak of VRE since 2014. 4 We compared the incidence of hospital-onset acquisitions (hospital-wide) during the 12 months before (Oct 2016 -Sept 2017) and 12 months after (Nov 2017 -Oct 2018) the start of the PT shortage. We analysed routine surveillance data; the first unique patient VRE and MRSA isolates from blood, tissue or fluid specimens were deemed indicators of morbidity. The interrupted time series was analysed in a regression framework with a generalised linear model; changes in usage trends and levels, adjusted for seasonality, were assessed. Structural breaks in the series were explored with a blinded generalised fluctuation test.Ethics approval was not required; we observed the guidance of the Outbreak Reports and Intervention studies of Nosocomial infection (ORION) statement. 5Twelve-month mean PT use declined from 44 defined daily doses (DDD)/1000 occupied bed-days (OBD) before the shortage to 5 DDD/1000 OBD; IVAC usage increased from 4 to 33 DDD/1000 OBD. As IVAC is a narrower spectrum antibiotic, total broad spectrum parenteral antimicrobial use fell from 129 DDD/1000 OBD before the shortage to 91 DDD/1000 OBD.A model with cyclical terms and a monthly lag effect best fitted the VRE acquisition time series, with a statistically significant change in level (P = 0.004) and trend (P = 0.002) at October 2017. A model with cyclical terms best fitted the MRSA time series, with a non-significant reduction in MRSA events (10% per month) during the shortage (Box). There were no meaningful structural breaks in either time series.There were 191 acquisitions of VRE and 53 of MRSA before the shortage; during the shortage, there were 101 (fall of 47%) and 31 (42% fewer) respectively. There were 24 sterile site detections of VRE and 49 of MRSA before the shortage, and eight (67% fewer) and 37 (24% fewer) during the shortage. Fifty-three health careassociated Clostridium difficile infections were detected before the shortage, 52 in the subsequent 12 months.

Think before you prescribe: how dentistry contributes to antibiotic resistance

“…A 2017 study from the John Hunter Hospital in Newcastle showed that by replacing a broad‐spectrum antibiotic with a narrow‐spectrum drug resulted in a 47% reduction in vancomycin‐resistant Enterococcus and a 42% decrease in MRSA cases respectively. Throughout this time, hand hygiene compliance was above 90% . Some of these strategies can be implemented effectively in private practice, such as encouraging participation in continuing education courses about therapeutics or conducting an audit of prescribing practice.…”

“…Throughout this time, hand hygiene compliance was above 90%. 52 Some of these strategies can be implemented effectively in private practice, such as encouraging participation in continuing education courses about therapeutics or conducting an audit of prescribing practice. Three audit cycles conducted over 3 years at a British emergency dental service found that by reinforcing correct documentation (e.g.…”

The effectiveness of an antimicrobial stewardship program in an Australian rural hospital

“…Antimicrobial resistance manifests itself through the development of multiresistant organisms such as vancomycin‐resistant Enterococcus (VRE) and methicillin‐resistant Staphylococcus aureus (MRSA) species. For example, it is well established that the use of broad‐spectrum antibiotics such as piperacillin–tazobactam is associated with an increase in hospital‐onset VRE and MRSA infections 3 . Antimicrobial resistance not only delays recovery and prolongs hospital stay but also associated with increased mortality.…”

“…For example, it is well established that the use of broad-spectrum antibiotics such as piperacillin-tazobactam is associated with an increase in hospital-onset VRE and MRSA infections. 3 Antimicrobial resistance not only delays recovery and prolongs hospital stay but also associated with increased mortality. It is estimated that there are 290 deaths annually from antimicrobial-resistant bacteria in Australia.…”

Antimicrobial resistance: think globally but act locally

“…A unit’s ecology can change over a relatively short period of time 4. We know for example that units that use ampicillin and gentamicin have lower AMR rates than those that use a third-generation cephalosporin,5 and a recent study showed where piperacillin-tazobactam became unavailable the resistance rates fell over months 6…”