Development and implementation of a short duration antibiotic therapy algorithm for uncomplicated gram-negative bloodstream infections

Patients were eligible for 7-day therapy if they had an uGNBSI, defined as meeting all of the following criteria by day 5 (with day 1 being the date of blood culture collection): no current or expected neutropenia (absolute neutrophil count [ANC] ≤ 500 cells/µL); no hematopoietic stem-cell transplantation in the previous 12 months; no ongoing therapy for graft-versus-host disease; no solid-organ transplant (SOT); adequate source control; no evidence of metastatic infection; no evidence or risk of endovascular infection (eg, prosthetic valve, vascular graft); no ongoing fevers or need for fluid resuscitation or vasopressors; and no persistently positive blood cultures, if repeat blood cultures were obtained. Statistical analysis A χ2 test was used to compare proportions for categorical variables, and the Mann-Whitney U test was used to compare medians and interquartile ranges for continuous variables. Because of the limited number of events in the baseline and intervention periods, an interrupted time-series analysis was not pursued. Baseline Characteristics and Clinical Outcomes in Patients Who Met Criteria for 7-Day Therapy for Gram-Negative Bloodstream Infections in the Baseline and Intervention Periods Characteristic Baseline (n=59) Intervention (n=55) P Value Age at admission, median y (IQR) 60 (46-71) 62 (51-70) 0.16 Pitt bacteremia score, median (IQR)a 1 (0-2) 1 (0-2) 0.19 ICU-level care on day 1, no. (%) 11 (18.6) 8 (14.5) 0.56 Follow-up blood culture collected during therapy, no. (%) 47 (79.7) 43 (78.2) 0.87 Source of bacteremia, no. (%) Urinary 27 (45.8) 22 (40.0) 0.64 Biliary 6 (10.2) 14 (25.5) 0.05 Intra-abdominal 12 (20.3) 14 (25.5) 0.57 Catheter-associated 11 (18.6) 2 (3.6) 0.02 Pulmonary 2 (3.4) 1 (1.8) 0.61 Skin and soft tissue infection 1 (1.7) 1 (1.8) 0.96 Unknown 0 1 (1.8) Causative organism, no. (%) Escherichia coli 29/64 (45.3) 30/59 (50.8) 0.66 Klebsiella pneumoniae 20/64 (31.3) 12/59 (20.3) 0.24 Klebsiella oxytoca 0 4/59 (6.8) Klebsiella aerogenes 3/64 (4.7) 1/59 (1.7) 0.36 Enterobacter spp 6/64 (9.4) 4/59 (6.8) 0.60 Serratia spp 3/64 (4.7) 4/59 (6.8) 0.63 Citrobacter spp 1/64 (1.6) 3/59 (5.1) 0.28 Proteus spp 1/64 (1.6) 1/59 (1.7) 0.95 Morganella spp 1/64 (1.6) 0 MDR organisms, no. (%)b Extended-spectrum β-lactamase producerc 7/64 (10.9) 8/59 (13.6) 0.66 Resistant to ≥3 antibiotic classes 1/64 (1.6) 1/59 (1.7) 0.95 Definitive oral antimicrobial therapy, no. (%) Ciprofloxacin 500 mg every 12 h 20 (33.9) 21 (38.2) Ciprofloxacin 750 mg