Caught Up in CAUTIs: The Importance of Diagnostic Stewardship

"Diagnostic stewardship" refers to the appropriate use of laboratory testing to guide patient management, including treatment, to optimize clinical outcomes and limit the spread of antimicrobial resistance.^[1] As an adjunct to existing antimicrobial stewardship programs, diagnostic stewardship for hospital-onset Clostridioides difficile infection (HO-CDI) has been shown to result in safe reductions in the nosocomial acquisition of this infection.^[2,3,4] We need diagnostic stewardship for other hospital-acquired infections as well.

Urine cultures rank high on the list of tests that are often performed unnecessarily or inappropriately. They are commonly ordered during diagnostic workups for the myriad presentations that might have an infectious etiology. However, because the bladder is not sterile, interpreting the significance of bacterial growth even in the presence of pyuria can be problematic, particularly in the absence of focal genitourinary symptoms.^[5] This applies to individuals with and without bladder catheters. In hospitalized patients who require Foley catheters, the dilemma is further complicated; the daily risk for bacteriuria is 3%-7%, and catheter-associated bacteriuria is an infrequent cause of nosocomial fever.^[6,7] The American College of Critical Care Medicine and Infectious Diseases Society of America recommend obtaining urine cultures only in certain cases for evaluation of fever in a catheterized critically ill patient: (1) kidney transplant recipients; (2) neutropenic patients; (3) patients who have recently undergone genitourinary surgery; and (4) patients with evidence of genitourinary obstruction.