Partial Oral Antibiotic Therapy May be Effective in Treating Complicated MRSA Among People with IDU
Clinical question: Are oral antibiotics effective in completing treatment for complicated methicillin-resistant Staphylococcus aureus (MRSA) among patients with injection drug use (IDU)?
Dr. Bredenberg
Background: Mounting evidence suggests that oral antibiotics may be effective in completing treatment for invasive infections after an initial period of intravenous (IV) antibiotic therapy. However, prior studies have not focused specifically on people with IDU and/or complicated MRSA bacteremia.
Study design: Retrospective cohort study
Setting: Single-site study at a large teaching hospital in a major metropolitan U.S. area
Synopsis: 238 patients with recent or active IDU during the five-year study period met the inclusion criteria of hospitalization for MRSA bacteremia with complications (endocarditis, septic arthritis, osteomyelitis, or epidural abscess). Patients were divided into the following three groups for comparison: 1. Standard of care—122 patients received a full four to six weeks of inpatient IV antibiotics; 2. Incomplete IV—36 patients received a partial course of IV antibiotics and were discharged without any further antimicrobial treatment; 3. Partial oral—69 patients received a partial course of IV antibiotics and were discharged with oral antibiotics to complete the course. Many patients in this group received intensive outpatient support.
Among patients who received at least 10 days of inpatient IV antibiotics, there was no difference in the primary outcome of treatment failure at 90 days between the group treated with standard-of-care therapy compared to the partial oral therapy group. Patients who received partial IV treatment only without oral therapy had a higher rate of treatment failure as compared to either of the other groups.
Bottom line: Patients with IDU and complicated MRSA infections who leave the hospital before completion of standard-of-care IV antimicrobial therapy should receive oral antibiotics at discharge.
Citation: Wildenthal JA, Atkinson A, et al. Outcomes of partial oral antibiotic treatment for complicated Staphylococcus aureus bacteremia in people who inject drugs. Clin Infect Dis. 2023;76(3):487-96.
Dr. Bredenberg is an assistant professor in the division of hospital medicine at the University of Colorado Anshutz Medical Campus in Aurora, Colo.