Antibiotics may not significantly improve clinical outcomes in patients with colon ischemia (CI), regardless of severity level, based on a retrospective study involving more than 800 patients.
Given these findings, clinicians “should consider not giving antibiotics to patients with CI,” reported lead author Paul Feuerstadt, MD, of Yale University, New Haven , Conn., and colleagues.
“CI is the most common ischemic injury to the GI tract,” the investigators wrote in their abstract, which was presented at the annual meeting of the American College of Gastroenterology. “The clinical utility of antibiotic treatment in CI is unclear and the literature is limited.”
Dr. Feuerstadt and colleagues analyzed data from 838 patients with biopsy-proven CI who were hospitalized between 2005 and 2017, of whom 413 and 425 had moderate and severe disease, respectively.
Across all patients, 67.7% received antibiotics. While there were no significant intergroup differences in age, Charlson Comorbidity Index, or sex, patients who received antibiotics were more likely to have severe CI (54.4% vs. 42.2%; P = .001), small-bowel involvement (12.0% vs. 5.7%; P = .04), and peritonitis (11.3% vs. 4.5%; P = 002), as well as require intensive care (26.1% vs. 19.9%; P = .04).
After adjusting for severity of CI, small-bowel involvement, and comorbidities, analysis revealed no significant associations between antibiotic use and 30-day mortality, 90-day mortality, 30-day colectomy, 90-day recurrence, 90-day readmission, or length of stay. The primary outcome, 30-day mortality, remained insignificant in subgroup analyses based on CI severity and age.
Patients were most frequently prescribed ciprofloxacin-metronidazole (57.1%), followed by piperacillin-tazobactam (13.2%), ceftriaxone-metronidazole (11.1%), and other antibiotics (18.5%).
When each of these antimicrobials was compared with no antibiotic usage, only piperacillin-tazobactam correlated with a higher rate of 30-day mortality, based on an adjusted odds ratio of 3.4 (95% CI, 1.5-8.0; P = .0003). But most patients who received piperacillin-tazobactam underwent colectomy, which prompted independent analyses of patients who underwent colectomy and those who did not undergo colectomy. These findings showed no difference in 30-day mortality based on the type of antibiotic used.
During an oral presentation at the meeting, coauthor Karthik Gnanapandithan, MD, of the Mayo Clinic in Jacksonville, Fla, said, “In practice, it is reasonable to still use antibiotics in patients with small bowel ischemia and those with severe CI with a high risk of poor outcomes pending prospective studies.”
According to John F. Valentine, MD, of the University of Utah, Salt Lake City, the present study “adds to the literature that questions the role of antibiotics in CI.”
Dr. Valentine noted that, even among patients with CI who have severe inflammation, “sepsis rarely occurs without frank perforation.”
Still, like Dr. Gnanapandithan, Dr. Valentine concluded that antibiotics are still a reasonable treatment option for certain patients with CI.
“The risks and potential benefits of antibiotics must be considered,” he said. “Until prospective studies are available, use of antibiotics in colon ischemia is reasonable in the setting of severe disease with peritoneal signs, signs of sepsis, pneumatosis, or portal venous gas.”
Dr. Feuerstadt disclosed relationships with Ferring/Rebiotix, Merck, and Roche. Dr. Valentine reported no relevant conflicts of interest.