SAN FRANCISCO – In gram-negative bloodstream infections, in patients who are stable at 48 hours, are no longer feverish, and whose infections aren’t invasive, it may be safe to step down from IV antibiotics to oral ciprofloxacin (PO). That is the tentative conclusion from a new single-center, retrospective chart review.
The study adds to growing suspicion among practitioners that stepping down may be safe in gram-negative patients, as well as mounting evidence that shorter treatment durations may also be safe, according to Gregory Cook, PharmD, who presentedat a poster session at an annual scientific meeting on infectious diseases. “We’re getting more aggressive” in backing off IV treatment, he said in an interview.
Oral medications are associated with shorter hospital stays and decreased costs.
Froedtert & the Medical College of Wisconsin, where the study was performed, switched some years ago from levofloxacin to ciprofloxacin for cost reasons. But ciprofloxacin has a lower bioavailability, and a recent study showed levofloxacin had less treatment failure at 90 days than ciprofloxacin. Levofloxacin is restricted at the institution and requires antibiotic stewardship approval for use, whereas ciprofloxacin can be used without approval.
But the researchers were concerned about bioavailability. “We like to think of ciprofloxacin as having excellent bioavailability, and it does, it has 80% bioavailability, but it’s still not exactly the same as levofloxacin. We wanted to look into this and see if we were doing our patients a disservice or not (by stepping down to ciprofloxacin),” said Dr. Cook, who is now the antimicrobial stewardship pharmacist at Children’s Hospital New Orleans. The results were reassuring. “Ultimately we were trying to see how our patients were doing on oral ciprofloxacin, and after 2-3 days of IV therapy, most of them did extremely well,” he said.
The researchers analyzed the records of 198 patients who presented with a monomicrobial, gram-negative bloodstream infection between January 2015 and January 2018, and who survived at least 5 days past blood culture collection. One hundred and three switched to PO within 5 days, while 95 remained on intravenous antibiotics for longer than 5 days. On average, patients in the PO group received IV antibiotics for 2 days, while the IV group averaged 15 days. Oral ciprofloxacin treatment length averaged 12 days.
The primary endpoint of treatment failure at 90 days, defined as recurrent infection or all-cause mortality, favored the PO group (1.9% versus 16.8%, P less than .01). This was likely because of patient selection, as those in the IV group tended to be more ill, according to Dr. Cook. More were immunosuppressed (41% IV versus 22% in PO group, P less than .01). There were more nonurinary sources of infection (41% in IV group, P less than .01; 65% urinary source in PO group). Thirty-four percent of the PO group had an infectious disease consult, compared with 60% of the IV group.
SOURCE: Gregory Cook et al. ID Week 2018.