Characteristics and outcomes of anti-infective de-escalation during health care-associated intra-abdominal infections.

BACKGROUND: De-escalation is strongly recommended for antibiotic stewardship. No studies have addressed this issue in the context of health care-associated intra-abdominal infections (HCIAI). We analyzed the factors that could interfere with this process and their clinical consequences in intensive care unit (ICU) patients with HCIAI.

METHODS: All consecutive patients admitted for the management of HCIAI who survived more than 3 days following their diagnosis, who remained in the ICU for more than 3 days, and who did not undergo early reoperation during the first 3 days were analyzed prospectively in an observational, single-center study in a tertiary care university hospital.

RESULTS: Overall, 311 patients with HCIAI were admitted to the ICU. De-escalation was applied in 110 patients (53%), and no de-escalation was reported in 96 patients (47%) (escalation in 65 [32%] and unchanged regimen in 31 [15%]). Lower proportions of Enterococcus faecium, nonfermenting Gram-negative bacilli (NFGNB), and multidrug-resistant (MDR) strains were cultured in the de-escalation group. No clinical difference was observed at day 7 between patients who were de-escalated and those who were not. Determinants of de-escalation in multivariate analysis were adequate empiric therapy (OR 9.60, 95% CI 4.02-22.97) and empiric use of vancomycin (OR 3.39, 95% CI 1.46-7.87), carbapenems (OR 2.64, 95% CI 1.01-6.91), and aminoglycosides (OR 2.31 95% CI 1.08-4.94). The presence of NFGNB (OR 0.28, 95% CI 0.09-0.89) and the presence of MDR bacteria (OR 0.21, 95% CI 0.09-0.52) were risk factors for non-de-escalation. De-escalation did not change the overall duration of therapy. The risk factors for death at day 28 were presence of fungi (HR 2.64, 95% CI 1.34-5.17), Sequential Organ Failure Assessment score on admission (HR 1.29, 95% CI 1.16-1.42), and age (HR 1.03, 95% CI 1.01-1.05). The survival rate expressed by a Kaplan-Meier curve was similar between groups (log-rank test p value 0.176).

CONCLUSIONS: De-escalation is a feasible option in patients with polymicrobial infections such as HCIAI, but MDR organisms and NFGNB limit its implementation.