By Stacey Butterfield
Kelly Cawcutt, MD, MS, FACP, came to the hospital medicine precourse at Internal Medicine Meeting 2023 ready to debunk dogma. "Why don't we use oral antibiotics for bloodstream infections? What's the reason?" she asked attendees Wednesday morning.
During her talk, Dr. Cawcutt, an associate professor in the divisions of infectious disease (ID) and pulmonary and critical care at the University of Nebraska Medical Center in Omaha, reviewed some reasons, or what she called "leading beliefs that are really obstacles" in transitioning inpatients with bloodstream infections from IV to oral therapy.
Those beliefs include that IV antibiotics provide earlier relief from symptoms, that they are more effective, and that they reduce reinfection and relapse rates. "Do we have data that proves that or is this just what we've chosen to believe as a community in medicine?" Dr. Cawcutt asked.
It's the latter, she asserted, offering a review published as a perspective in Open Forum Infectious Diseases in 2023. It found nine trials demonstrating the equality of oral to IV routes for osteomyelitis, eight trials finding equality in bacteremia (plus two where oral was superior), and, for endocarditis, two trials that found them to be equal, and one in which oral came out ahead.
Dr. Cawcutt also reported how many trials supported the superiority of IV antibiotics for these indications. "Zero," she said. "There was not a single study that proves that IV is actually superior."
There are a lot of other reasons to want to switch patients to oral antibiotics, starting with length of stay, she noted. "How many of you, if you are working as a hospitalist, have never been under pressure to get your patients out faster?" Dr. Cawcutt asked, to laughter from the audience.
Add to that the benefits of lower risk of infection or thrombosis from lines, reduced costs and antibiotic resistance, and less worry about patients with injection drug use. "This is a profound issue in our communities, as far as rising numbers of patients whom we may not be comfortable sending out … having an open line facilitating IV drug use," she said. "By transitioning to oral, we can give them appropriate therapy and definitive management without having that risk or keeping them in the hospital."
That said, there are a number of things to consider before putting a patient with a bloodstream infection on oral therapy, including the differing bioavailability of oral medications, Dr. Cawcutt added. Those with great bioavailability include fluoroquinolones, doxycycline, minocycline, tetracycline, linezolid, metronidazole, trimethoprim/sulfamethoxazole, cephalexin, and the azoles.
Patients should also be clinically stable before they undergo a switch, and you should of course be sure the causative organism is susceptible to an available oral medication.
For a full list of the relevant considerations, she recommended a 2020 review in JAMA Internal Medicine. "You can take this article home and you can think through how to do this, especially if you do not have ID physicians readily available," Dr. Cawcutt said.
However, if subspecialty expertise is available, take advantage of it when considering oral antibiotics for a patient with a bloodstream infection, she added. "You have should have a very low threshold to consult ID or talk with your pharmacist about your dose, your drug, and duration of therapy to make sure that you have a right match for those patients." ■