Antibiotic prescribing for adults with group A streptococcal bacteremia in a large healthcare system

Abstract

Purpose: Limited data exist regarding treatment of invasive group A streptococcal (GAS) infections, including safety and efficacy of oral (PO) step-down therapy. We sought to describe current prescribing practices and clinical outcomes for patients with GAS bacteremia across a large health system, including a prespecified subset of patients who stepped down to PO antibiotics. Methods: This retrospective cohort study included adult patients with a positive blood culture for GAS between July 2018 and July 2021. Primary outcomes included frequency of PO step-down, total duration of therapy, duration of intravenous (IV) therapy prior to PO switch, and antimicrobial selection. Secondary outcomes included length of stay (LOS), mortality, adverse events, and clinical failure leading to readmission within 90 days. Results: In total, 280 patients met inclusion criteria. Of these, 46.7% were stepped down to PO antibiotics. Median total duration of therapy was 15 days. Median duration of IV therapy prior to PO switch was 5 days. The predominant definitive antibiotic choice was a beta-lactam. Median LOS was 5 days. Ninety-day mortality was 16.7%. One patient developed an occluded line and one developed Clostridioides difficile-associated diarrhea within 90 days. Ninety-day readmission due to clinical failure was 12.5%. Among cases of uncomplicated skin and soft tissue source, mortality (6.1% vs 2.4%) and readmission (15.2% vs 16.9%) were similar between definitive IV and PO groups. Conclusions: Group A streptococcal bacteremia is a severe infection with a high readmission and mortality rate. Use of PO step-down therapy was common with similar readmission and mortality rates compared with definitive IV therapy.