Follow-up blood cultures do not reduce mortality in hospitalized patients with Gram-negative bloodstream infection: a retrospective population-wide cohort study

• DOI: 10.1016/j.cmi.2024.03.025
• Publication Date: 2024-03-27T17:56:45Z
• Authors: Sean W.X. Ong; Jin Luo; Daniel J. Fridman; Samantha M. Lee; Jennie Johnstone; Kevin L. Schwartz; Christina Diong; Samir N. Patel; Derek MacFadden; Bradley Langford; Steven Y.C. Tong; Kevin A. Brown; Nick Daneman
• Keywords: Interquartile range; Bacteremia; Bloodstream infection

ObjectivesThe utility of follow-up blood cultures (FUBCs) in patients with Gram-negative bloodstream infection (GN-BSI) is controversial. Observational studies have suggested significant mortality benefit, but may be limited by single-center designs, immortal time bias, and residual confounding. We examined the impact FUBCs on GN-BSI a retrospective population-wide cohort study Ontario, Canada.MethodsAdult hospitalized between April-2017 December-2021 were included. Primary outcome was all-cause within 30 days. FUBC treated as time-varying exposure. Secondary outcomes 90-day mortality, length stay (LOS), number days alive out hospital at (DAOH30) 90 (DAOH90) days.Results34,100 included; 8807 (25.8%) received FUBC, which 966 (11.0%) positive. Median proportion receiving 18.8% (interquartile range 10.0–29.7%, 0–66.1%) across 101 hospitals; this correlated positivity contamination rate. 890 (10.1%) group 2263 (8.9%) no died In fully-adjusted model, there association (HR 0.97, 95% CI 0.90–1.04). Patients had significantly longer LOS (median 11 vs 7 days; adjusted RR 1.18, 1.16–1.21) fewer DAOH30/DAOH90.ConclusionsFUBC collection varies widely hospitals associated prolonged hospitalization without clear survival benefit. Residual confounding present given observational design. Clear benefit should demonstrated randomized trial before widespread adoption routine FUBC.