Epidemiology and Outcomes of Antibiotic De-escalation in Patients with Suspected Sepsis in US Hospitals

We applaud Kam et al. for their important work in this issue of Clinical Infectious Diseases suggesting improved outcomes in patients with suspected sepsis who underwent appropriate deescalation from anti-pseudomonal and anti-MRSA agents when resistant pathogens were not identified.The authors propose several biologically plausible mechanisms by which de-escalation may improve patient outcomes including reduced antibiotic toxicities, less alteration to the gut microbiome, and fewer new antibiotic-resistant infections.However, there exists significant diversity in terms of spectrum of activity within pseudomonal and MRSA sparing agents that may impact patient outcomes.Recently, authors have used spectrum scores as a means to quantify antibiotic activity and define de-escalation (1).One such example is the antibiotic spectrum index (ASI), which assigns each antibiotic a score ranging from 1 (oxacillin) to 13 (tigecycline), with broader coverage being assigned a higher score (2).When multiple agents are used on the same day, the scores are added together.Identifying de-escalation practices using a reduction in ASI has been evaluated in patients