Diagnostic stewardship is more effective than antibiotic stewardship at reducing unnecessary antibiotic use for patients treated for urinary tract infections who have asymptomatic bacteriuria, according to research presented at IDWeek. UTIs are one of the most common bacterial infections and a significant driver of global antimicrobial resistance.

In a four-year study across 46 hospitals that implemented pay-for-performance metrics related to unnecessary treatment of ASB, the percentage of patients treated with antibiotics for UTIs who had ASB declined from 29.0% to 16.9%. Diagnostic stewardship — making sure patients receive the right tests at the right time — appeared responsible for nearly all improvement.

“Most efforts to combat antimicrobial resistance have focused on prescribing, but our research indicates that more progress can be made by looking further upstream — before a prescription is ever written,” said Valerie Vaughn, MD, MSc, director of hospital medicine research at the University of Utah. “Diagnostic stewardship is an important and effective part of overall responsible antibiotic use in healthcare settings.”

About one-third of hospitalized patients treated for UTIs have ASB, which is when bacteria are in the urine but do not present symptoms or cause infection. Up to 80% of patients who have ASB are treated with antibiotics that they don't need, which can lead to increased antibiotic resistance without improving patient outcomes.

“Our study focused on hospitalized patients, but it’s a critical issue for patients in long-term care or skilled nursing facilities, because patients who have asymptomatic bacteria tend to be older and chronically ill,” said Vaughn. “These patients are already more likely to experience adverse events from antibiotics, so responsible antibiotic usage is especially important for those healthcare providers to address.”

In addition to Vaughn, co-authors of the paper include: Ashwin Gupta, MD; Lindsay A. Petty, MD; Anurag N. Malani, MD, FIDSA, FSHEA; Danielle Osterholzer, MD; Payal K. Patel, MD, MPH; Mariam Younas, MD; Steven Bernstein, MD, MPH; David Ratz, MS; Elizabeth McLaughlin, BSN, MS; Tawny Czilok, MHI, BSN, RN; Jennifer Horowitz, MA; Scott A. Flanders, MD; and Tejal N. Gandhi, MD.