The relationship between Gram-negative colonization and bloodstream infections in neonates: a systematic review and meta-analysis.

OBJECTIVES: Neonates admitted to neonatal intensive care units (NICU) are at significant risk of developing bloodstream infections (BSIs). Gram-negative bacteria (GNB) both colonize and infect, but the association between these entities is unclear. By conducting a systematic literature review, we aimed to explore the impact of factors on the association between GN colonization and GN-BSI at both baby-level and unit-level. METHODS: We searched Medline, Embase, and Cochrane Library. Observational cohort studies published after 2000 up to June 2016 reporting data on the total number of neonates (0-28 days) colonized with GNB assessed by rectal/skin swab culture and the total number of neonates with GN-BSI (same bacteria) were included. Studies were excluded if data on skin/rectal colonization, neonates, and GNB could not be identified separately. Meta-analyses along with multivariate meta-regression with a random-effect model were performed to investigate factors associated with the GN colonization and GN-BSI at baby-level and unit-level. RESULTS: Twenty-seven studies fulfilled our inclusion criteria, 15 for the baby-level and 12 for the unit-level analysis. Study heterogeneity was high, with suboptimal overall quality of reporting assessed by the STROBE-NI statement (44.8% of items adequately reported). In 1984 colonized neonates, 157 (7.9%) developed GN-BSI compared with 85 of 3583 (2.4%) non-colonized neonates. Considerable heterogeneity was observed across studies. Four factors were included in the meta-regression model: gross domestic product (GDP), pathogen, outbreak, and frequency of screening. There was no statistically significant impact of these factors on GN colonization and GN-BSI in baby-level. We were unable to perform the multivariate meta-regression because of insufficient reported data for unit-level. CONCLUSIONS: Study limitations include the small number and the high heterogeneity of the included studies. While this report shows a correlation between colonization and BSI risk, these data currently do not support routine screening for GNB. Analysis of large cohorts of colonized neonates with clinical outcomes is still needed to define the major determinants leading from colonization to infection.

Lack of evidence for the efficacy of enhanced surveillance compared to other specific interventions to control neonatal healthcare-associated infection outbreaks.

BACKGROUND: Despite current prevention efforts, outbreaks of healthcare-associated infections in neonatal units remain high globally, with a considerable burden of mortality and morbidity. METHODS: We searched Medline, Cochrane Library and Outbreak database to identify studies of neonatal healthcare-associated outbreaks between 2005 and 2015 that described interventions to control outbreaks. All studies were evaluated using the ORION guidance. RESULTS: Thirty studies were identified including 17 102 infants of whom 664 (3.9%) became infected. No single intervention was identified that reduced duration or mortality. Studies that introduced multiple interventions had significantly reduced case fatality ratio and outbreak duration compared to those that used basic surveillance only. Low and low-middle income countries reported the fewest interventions to control outbreaks and these studies were also associated with higher mortality than that found in middle and high income countries. CONCLUSIONS: Systematic reporting and formal evaluation of interventions used to reduce healthcare-associated neonatal infection outbreaks is key to identifying containment strategies worldwide.