Early Antibiotic De-escalation in Patients With Severe Infections Due to Bloodstream Infection by Enterobacterales: A Post Hoc Analysis of a Prospective Multicentre Cohort.

BACKGROUND: Data about antibiotic de-escalation in sepsis associated with the bloodstream and caused by Enterobacterales are scarce. The objectives of this study are to identify factors associated with early de-escalation and to analyse the impact of de-escalation on mortality in patients with Enterobacterales bloodstream infection (BSI) with a Sequential Organ Failure Assessment (SOFA) score ≥ 2. METHODS: A prospective, multicentre cohort study was performed including episodes of BSI due to Enterobacterales and a SOFA score ≥ 2 who were receiving an active antipseudomonal ß-lactam; the isolate should be susceptible to at least 1 narrower-spectrum antibiotic. Variables associated with de-escalation were identified using logistic binary regression. The association of de-escalation with 30-day mortality was investigated. Confounding was controlled by calculating a propensity score used as covariate, as matching variable, and for inverse probability treatment weighting. RESULTS: Of the 582 patients included, de-escalation was performed in 311 (53.4%). Neutropenia (adjusted odds ratio [aOR] = 0.37; 95% confidence interval [95% CI] = 0.18-0.75), central venous catheter (aOR = 0.52; 95% CI = 0.32-0.83), and extended-spectrum ß-lactamase (ESBL)-producing isolate (aOR = 0.28; 95% CI = 0.17-0.48) were negatively associated with de-escalation, and urinary tract source was positively associated (aOR = 2.27; 95% CI = 1.56-3.33). The 30-day mortality was 6.8% (21 patients) in de-escalated patients and 14.4% (39) in not de-escalated patients (relative risk, 0.63; 95% CI = 0.44-0.89). In multivariate analysis including the propensity score, de-escalation was not associated with mortality (AOR = 0.98; 95% CI = 0.39-2.47) and was protective in the case of urinary or biliary tract source (AOR = 0.31, 95% CI = 0.09-1.06). Matched and inverse probability treatment weighting analysis showed similar results. CONCLUSIONS: These results suggest that early de-escalation from antipseudomonal ß-lactams is safe in patients with Enterobacterales bacteremia and SOFA ≥ 2.

A comprehensive, predictive mortality score for patients with bloodstream infections (PROBAC): a prospective, multicentre cohort study.

OBJECTIVES: Bloodstream infections (BSI) are an important cause of mortality, although they show heterogeneity depending on patients and aetiological factors. Comprehensive and specific mortality scores for BSI are scarce. The objective of this study was to develop a mortality predictive score in BSI based on a multicentre prospective cohort. METHODS: A prospective cohort including consecutive adults with bacteraemia recruited between October 2016 and March 2017 in 26 Spanish hospitals was randomly divided into a derivation cohort (DC) and a validation cohort (VC). The outcome was all-cause 30-day mortality. Predictors were assessed the day of blood culture growth. A logistic regression model and score were developed in the DC for mortality predictors; the model was applied to the VC. RESULTS: Overall, 4102 patients formed the DC and 2009 the VC. Mortality was 11.8% in the DC and 12.34% in the CV; the patients and aetiological features were similar for both cohorts. The mortality predictors selected in the final multivariate model in the DC were age, cancer, liver cirrhosis, fatal McCabe underlying condition, polymicrobial bacteraemia, high-risk aetiologies, high-risk source of infection, recent use of broad-spectrum antibiotics, stupor or coma, mean blood pressure <70 mmHg and PaO2/FiO2 ≤ 300 or equivalent. Mortality in the DC was <2% for ≤2 points, 6%-14% for 3-7 points, 26%-45% for 8-12 points and ≥60% for ≥13 points. The predictive score had areas under the receiving operating curves of 0.81 (95% CI 0.79-0.83) in the DC and 0.80 (0.78-0.83) in the VC. CONCLUSIONS: A 30 day mortality predictive score in BSI with good discrimination ability was developed and internally validated.

Integrase strand transfer inhibitor resistance mediated by R263K plus E157Q in a patient with HIV infection treated with bictegravir/tenofovir alafenamide/emtricitabine: case report and review of the literature.

OBJECTIVES: The in vivo selection of E157Q plus R263K has not been reported in patients treated with coformulated bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF). To the best of our knowledge, we hereby report the first case of high-grade INSTI resistance associated with the presence of these aminoacidic substitutions in a treatment-experienced HIV patient treated with BIC/FTC/TAF. METHODS: Clinical case report and review of the literature. RESULTS: A heavily treatment-experienced patient was switched to BIC/FTC/TAF due to drug-drug interactions after being diagnosed with disseminated Mycobacterium avium-intracellulare disease. He had been treated before with raltegravir with poor adherence. No mutations in the integrase gene were detected 1 year after finishing treatment with raltegravir. Months after being switched to BIC/FTC/TAF, and again with poor adherence documented, virological failure (VF) was detected. The polymorphic substitution E157Q and the resistance mutation R263K in the integrase gene were detected, as well as M184V, among other mutations in the reverse transcriptase gene. The patient is currently being treated with dolutegravir q12h plus boosted darunavir along with directly observed treatment, and for the first time in 20 years, plasmatic viral load values are below 100 copies/mL. CONCLUSIONS: This case illustrates that the combination of E157Q and R263K plus M184V can be selected in vivo in a clinical scenario of poor adherence with BIC/FTC/TAF, although it is a very rare phenomenon. Previous VF with first-generation integrase strand transfer inhibitors (INSTIs) should be kept in mind when switching patients to second-generation INSTIs.