Risk factors for community-acquired Escherichia coli bacteraemia: a systematic review protocol

Introduction: Rates of community-acquired Escherichia coli bacteraemia (ECB) have been consistently rising. As rates of antimicrobial resistance (AMR), particularly in Gram-negative bacteria, are also increasing, this is of concern both for management of individual patients and healthcare systems. There is currently little data on the risk factors for development of community-acquired ECB: this review aims to identify these risk factors in order to inform community interventions to reduce ECB as well as antibiotic prescribing policy.

Methods and analysis: We will search Medline (Ovid), Embase (Ovid), Web of Science/Scopus and the Cochrane Central Register of Controlled Trials for published reports on observational and experimental primary research studies involving patients admitted to hospital with community-acquired ECB. Two reviewers will independently screen the studies for eligibility, perform data collection and assess study quality and risk of bias. Random effects meta-analyses will be performed if appropriate.

Ethics and dissemination: No primary data will be collected for this study and so formal ethical approval is not required. We will publish the results of our review in relevant peer-reviewed medical journals, and will also seek to present them at relevant medical conferences.

PROSPERO registration number:CRD42018104402

Thirty day all-cause mortality in patients with Escherichia coli bacteraemia in England

Escherichia coli is the commonest cause of bacteraemia in England, with an incidence of 50.7 cases per 100 000 population in 2011. We undertook a large national study to estimate and identify risk factors for 30-day all-cause mortality in E. coli bacteraemia patients. Records for patients with E. coli bacteraemia reported to the English national mandatory surveillance system between 1 July 2011 and 30 June 2012 were linked to death registrations to determine 30-day all-cause mortality. A multivariable regression model was used to identify factors associated with 30-day all-cause mortality. There were 5220 deaths in 28 616 E. coli bacteraemia patients, a mortality rate of 18.2% (95% CI 17.8-18.7%). Three-quarters of deaths occurred within 14 days of specimen collection. Factors independently associated with increased mortality were: age < 1 year or > 44 years; an underlying respiratory or unknown infection focus; ciprofloxacin non-susceptibility; hospital-onset infection or not being admitted; and bacteraemia occurring in the winter. Female gender and a urogenital focus were associated with a reduction in mortality. This is the first national study of mortality among E. coli bacteraemia patients in England. Interventions to reduce mortality need to be multifaceted and include both primary and secondary healthcare providers. Greater awareness of the risk factors for and symptoms of E. coli bacteraemia may prompt earlier diagnosis and treatment. Changes in antimicrobial resistance patterns need to be monitored for their potential impact on infection and mortality.