Utility of Differential Time to Positivity in Diagnosing Central Line-Associated Bloodstream Infections: A Systematic Review and Meta-Analysis.

BACKGROUND: Differential time to positivity (DTP), defined as pathogen growth at least 2 hours earlier from catheter versus paired peripheral blood cultures, is sometimes used to diagnose central line-associated bloodstream infections (CLABSIs). Previous studies assessing DTP, however, have been small, provided conflicting results, and did not assess heterogeneity across important subgroups. METHODS: We systematically reviewed the diagnostic characteristics of DTP for CLABSI using MEDLINE, Embase, WoS, CINAHL, LILACS, AMED, and the Cochrane database. Studies were included if they reported sensitivities, specificities, predictive values, likelihood ratios, or 2 × 2 tables of DTP for diagnosing CLABSI. Extracted data were analyzed by using forest plots, bivariate model meta-analysis, and QUADAS-2 quality assessment. RESULTS: We identified 274 records, of which 23 met the criteria for meta-analysis. Among 2526 suspected CLABSIs, DTP demonstrated a summary sensitivity of 81.3% (95% confidence interval [CI]: 72.8%-87.7%), specificity of 91.8% (95% CI: 84.5%-95.8%), positive likelihood ratio of 9.89 (95% CI: 5.14-19.00), and negative likelihood ratio of 0.20 (95% CI: .14-.30). Covariate analysis based on catheter duration, study design, and patient immune status demonstrated no significant differences. However, DTP performed worse for Staphylococcus aureus (low sensitivity but high specificity) and Candida (high sensitivity but low specificity) compared to other organisms. CONCLUSIONS: DTP performs well in ruling CLABSIs in or out. Obtaining paired catheter and peripheral blood cultures for DTP when the infectious source is unclear may prevent unnecessary line removal and diagnostic tests. However, this must be balanced against higher contamination rates from catheter cultures.

Relationship between dietary patterns and COPD: a systematic review and meta-analysis.

BACKGROUND: Findings from previous studies reporting on the associations between chronic obstructive pulmonary disease (COPD) and various dietary patterns have been inconsistent. This review aims to summarise the evidence on the strength of the association between dietary patterns and the prevalence and incidence of COPD. METHODS: We conducted a comprehensive search of seven databases between 1 January 1980 and 30 November 2019. Two reviewers independently reviewed each manuscript through the screening, selection, data extraction and quality assessment stages. Data from eight observational studies that met the inclusion criteria were extracted and random-effects meta-analysis was subsequently conducted. RESULTS: Eight observational studies (all eight reporting on healthy dietary patterns and three on unhealthy dietary patterns) met the inclusion criteria and data were extracted to include in the meta-analysis. Consumption of a healthy dietary pattern was associated with a lower risk of COPD (pooled OR 0.88, 95% CI 0.82-0.94). Consumption of unhealthy dietary patterns was associated with a higher risk of COPD (OR 1.22, 95% CI 0.84-1.76); however, the results were not statistically significant and had high heterogeneity (I2=91%). CONCLUSION: Our results suggests that healthy dietary patterns are associated with a lower prevalence of COPD, while unhealthy dietary patterns are not. More studies, particularly adequately powered longitudinal studies, are needed to further elucidate the effects of healthy and unhealthy dietary patterns on risk of COPD.