Rate and predictors of blood culture positivity after antibiotic administration: a prospective single-center study.

PURPOSE: Blood culture obtainment prior to antibiotic administration, in patients with suspected infection, is considered the best practice in international guidelines. However, there is little data regarding the effect of a single dose of antibiotics on blood culture sterilization. METHODS: We conducted a prospective study, enrolling consecutive patients with suspected infection, hospitalized in an internal medicine ward between December 2019 and January 2023. Included patients had a positive blood culture prior to antibiotic administration and a set of blood cultures taken within 24 h after a single dose of antibiotics. The rate of patients with pathogen isolation after antibiotic administration was assessed. Logistic regression was performed to examine factors associated with blood culture positivity. RESULTS: A total of 155 patients were recruited for the study of which 131 (50.8% female 77.5 ± 13.4 years) met the inclusion criteria. The overall rate of patients with a positive blood culture after a single dose of antibiotics was 42.0% (55/131 patients). Increasing time between antibiotic administration and post-antibiotic culture was an independent predictor for blood culture sterilization (odds ratio 0.89 [95% confidence interval, 0.83-0.97; p = 0.006] for every 60 min). Blood culture volume was an independent predictor for blood culture positivity in a sensitivity analysis which included 82 patients (OR = 1.26 [95% CI 1.03-1.57] for every 1 ml increase; p = 0.024). CONCLUSION: Blood culture positivity is reduced by antimicrobial therapy but remains high after a single dose of antibiotics. If cultures are not obtained prior to antibiotic administration, they should be obtained as soon as possible afterwards.

Safety and outcomes of an early discharge strategy with oxygen home therapy in stable severe COVID-19 patients.

BACKGROUND: COVID-19 disease leads to prolonged hospitalisations and adverse outcomes. We describe our strategy for routine early discharge of severe COVID-19 patients with home oxygen during the Delta variant surge. METHODS: Our strategy included COVID-19 patients requiring oxygen support via nasal cannula, with stabilised but not yet improved respiration (intervention group), that followed strict criteria. Severe COVID-19 patients discharged after improved respiration were considered the control group for comparison. Outcomes included readmissions from active COVID-19 and 30-day mortality. RESULTS: The intervention group included 129 patients, and the control 150. The groups' baseline characteristics were similar, although the control group had more advanced COVID-19 severity. Among the intervention group, 23 (17.8%) had readmissions secondary to active COVID-19, compared to none in the control group. The 30-day mortality rate was similar between the groups (5% vs. 7%). The intervention led to a shorter hospital stay [median 3 days (IQR 2-4) vs. 6 days (IQR 4-9), p < .01], while a very short hospitalisation was associated with readmissions (2.8 vs. 3.5 days, p = .02). A subsequent critical disease or death after the intervention occurred in old (81 years), multimorbid (3.4 ± 1.4) patients with a high percentage of acute kidney injury during their first hospitalisation (50%). CONCLUSIONS: Our discharge strategy led to a short hospital stay, a high readmission rate, and similar long-term outcomes. Considering the difference in disease severity before discharge, this intervention cannot be considered safe for our study population. Correct patient selection is crucial to ensure patient safety when considering early discharge.

Trimethoprim-sulfamethoxazole vs. colistin or ampicillin-sulbactam for the treatment of carbapenem-resistant Acinetobacter baumannii: A retrospective matched cohort study.

OBJECTIVES: This study aimed to assess the effectiveness of trimethoprim-sulfamethoxazole (TMP/SMX) as monotherapy for the treatment of carbapenem-resistant Acinobacter baumannii (A. baumannii) (CRAB) infections. METHODS: This retrospective cohort study included patients receiving TMP/SMX as the main treatment for severe infections caused by CRAB, who were matched with patients treated with colistin or ampicillin-sulbactam (AMP/SUL) by age, Charlson score, department, and source of infection. Outcomes were compared among all patients and in a subgroup of propensity-score (PS) matched patients. The PS matching was performed using a match tolerance of 0.15 with replacement. RESULTS: Fifty-three patients treated with TMP/SMX and 83 matched patients treated with colistin or AMP/SUL were included. Variables that were independently significantly associated with TMP/SMX treatment included admission for infection and septic shock, while abnormal cognition on admission and intensive care unit admission were associated with colistin or AMP/SUL treatment. All-cause 30-day mortality was lower with TMP/SMX compared with the comparator antibiotics among all patients (24.5%, 13 of 53 vs. 38.6%, 32 of 83, P=0.09) and in the PS-matched subgroup (29%, 9 of 31 vs. 55.2% 16 of 29, P=0.04). Treatment failure rates were not significantly different overall (34%, 18 of 53 vs. 42.4%, 35 of 83, P=0.339) and in the PS-matched subgroup (35.5%, 11 of 31 vs. 44.8%, 13 of 29, P=0.46). Time to clinical stability and hospitalization duration were significantly shorter with TMP/SMX. Patients treated with TMP/SMX probably had less severe infections than those treated with other antibiotics, even after matching. CONCLUSIONS: TMP/SMX might be a valuable treatment option for TMP/SMX-susceptible CRAB infections. Given the very limited available treatment options, further studies assessing its effectiveness and safety are necessary.