Early Switch From Intravenous to Oral Antibiotics in Skin and Soft Tissue Infections: An Algorithm-Based Prospective Multicenter Pilot Trial.

Background: In hospitalized patients with skin and soft tissue infections (SSTIs), intravenous (IV) empiric antibiotic treatment is initiated. The best time point for switching from IV to oral treatment is unknown. We used an algorithm-based decision tree for the switch from IV to oral antibiotics within 48 hours and aimed to investigate the treatment outcome of this concept. Methods: In a nonrandomized trial, we prospectively enrolled 128 patients hospitalized with SSTI from July 2019 to May 2021 at 3 institutions. Clinical and biochemical response data during the first week and at follow-up after 30 days were analyzed. Patients fulfilling criteria for the switch from IV to oral antibiotics were assigned to the intervention group. The primary outcome was a composite definition consisting of the proportion of patients with clinical failure or death of any cause. Results: Ninety-seven (75.8%) patients were assigned to the intervention group. All of them showed signs of clinical improvement (ie, absence of fever or reduction of pain) within 48 hours of IV treatment, irrespective of erythema finding or biochemical response. The median total antibiotic treatment duration was 11 (interquartile range [IQR], 9-13) days in the invention group and 15 (IQR, 11-24) days in the nonintervention group (P < .001). The median duration of hospitalization was 5 (IQR, 4-6) days in the intervention group and 8 (IQR, 6-12) days in the nonintervention group (P < .001). There were 5 (5.2%) failures in the intervention group and 1 (3.2%) in the nonintervention group after a median follow-up of 37 days. Conclusions: In this pilot trial, the proposed decision algorithm for early switch from IV to oral antibiotics for SSTI treatment was successful in 95% of cases. Clinical Trials Registration. ISRCTN15245496.