A Large, Refractory Nosocomial Outbreak of Klebsiella pneumoniae Carbapenemase-Producing Escherichia coli Demonstrates Carbapenemase Gene Outbreaks Involving Sink Sites Require Novel Approaches to Infection Control.

Carbapenem-resistant Enterobacteriaceae (CRE) represent a health threat, but effective control interventions remain unclear. Hospital wastewater sites are increasingly being highlighted as important potential reservoirs. We investigated a large Klebsiella pneumoniae carbapenemase (KPC)-producing Escherichia coli outbreak and wider CRE incidence trends in the Central Manchester University Hospital NHS Foundation Trust (CMFT) (United Kingdom) over 8 years, to determine the impact of infection prevention and control measures. Bacteriology and patient administration data (2009 to 2017) were linked, and a subset of CMFT or regional hospital KPC-producing E. coli isolates (n = 268) were sequenced. Control interventions followed international guidelines and included cohorting, rectal screening (n = 184,539 screens), environmental sampling, enhanced cleaning, and ward closure and plumbing replacement. Segmented regression of time trends for CRE detections was used to evaluate the impact of interventions on CRE incidence. Genomic analysis (n = 268 isolates) identified the spread of a KPC-producing E. coli outbreak clone (strain A, sequence type 216 [ST216]; n = 125) among patients and in the environment, particularly on 2 cardiac wards (wards 3 and 4), despite control measures. ST216 strain A had caused an antecedent outbreak and shared its KPC plasmids with other E. coli lineages and Enterobacteriaceae species. CRE acquisition incidence declined after closure of wards 3 and 4 and plumbing replacement, suggesting an environmental contribution. However, ward 3/ward 4 wastewater sites were rapidly recolonized with CRE and patient CRE acquisitions recurred, albeit at lower rates. Patient relocation and plumbing replacement were associated with control of a clonal KPC-producing E. coli outbreak; however, environmental contamination with CRE and patient CRE acquisitions recurred rapidly following this intervention. The large numbers of cases and the persistence of blaKPC in E. coli, including pathogenic lineages, are of concern.

Screening for carbapenemase-producing Enterobacteriaceae in previous carriers readmitted to hospital: evaluation of a change in screening policy.

Carbapenemase-producing Enterobacteriaceae (CPE) are a growing problem in UK hospitals. Preventing transmission requires early detection. This study evaluates a new screening policy for patients with a history of blaKPC-associated CPE (KPC-CPE) in a higher incidence hospital. Previous policy assumed 'once positive always positive'. New policy uses rapid screening and risk assessment. Results show that most (76.5%) patients with a history of KPC-CPE do not have detectable KPC-CPE on readmission or during their subsequent hospital stay but that repeat screening after an initial negative result is required. The new policy takes a risk-based approach while prioritizing isolation facilities in a higher incidence trust.

Active case finding for carbapenemase-producing Enterobacteriaceae in a teaching hospital: prevalence and risk factors for colonization.

BACKGROUND: Over the past decade, the prevalence of carbapenemase-producing Enterobacteriaceae (CPE) has increased. Whilst basic infection prevention and control practices reduce the risk of transmission, cases of unrecognized carriage pose a potential risk of transmission. AIM: To estimate the prevalence of CPE and explore risk factors associated with colonization within a large teaching hospital with an established CPE outbreak. METHODS: All inpatients that had not previously tested positive for CPE were offered testing. Demographic and hospital episode data were also collected, together with antibiotic and proton pump inhibitor (PPI) use in the preceding 24h. FINDINGS: This study identified 70 CPE-positive cases (26 newly identified and 44 previously known) and 592 CPE-negative cases, giving a combined prevalence of 11% [95% confidence interval (CI) 8-13]. Medication (antibiotic and PPI use), previous admission, ethnicity and length of stay were assessed as risk factors for colonization, and none were found to be independently associated with CPE colonization. Using logistic regression, age [odds ratio (OR) 1.03, 95% CI 1.01-1.07] and antibiotic use (OR 2.55, 95% CI 1.08-6.03) were the only risk factors significantly associated with CPE colonization. CONCLUSION: This study has added to the evidence base by estimating the prevalence of CPE among inpatients in an acute hospital with an established CPE outbreak. A case-finding exercise was feasible and identified a number of new cases. Despite a small sample size, increasing age and prescription of an antibiotic on the day of testing were significantly associated with CPE colonization.

Evaluation of patient-held carbapenemase-producing Enterobacteriaceae (CPE) alert card.

Public Health England recommends patient-held cards for those colonized with carbapenemase-producing Enterobacteriaceae (CPE). Alert cards were provided to 104 CPE-positive inpatients, with follow-up at six months. Excluding those who died, the response rate was 39%. Sixteen patients (46%) recalled receiving the card; 13 (81%) of these retained it, most (64%) of whom reported using it. This is the first evaluation of a patient-held alert card for any antimicrobial-resistant (AMR) bacteria in the UK. This study demonstrated that, when retained, CPE alert cards can be an effective communication tool. Further work is required to evaluate effectiveness and improve retention.