Rifaximin Resistance to C difficile in Patients With Cirrhosis
Most causative C difficile strains were found to be rifaximin-resistant and belong mainly to ribotype 001.
Rifaximin-resistant Clostridium difficile was common among patients with cirrhosis receiving rifaximin as hepatic encephalopathy prophylaxis, according to the results of a study published in Clinical Infectious Diseases.
In this retrospective chart review study, the incidence and clinical characteristics of C difficile infection in patients with cirrhosis were evaluated at a single institution. The researchers performed ribotyping and antimicrobial susceptibility testing on all stool samples that were collected.
Of the 388 patients with cirrhosis that were included, 127 patients had at least 1 diarrhea episode and a stool sample analyzed. A total of 46 cases of C difficile were identified, and 30.4% of patients with C difficile were taking rifaximin as prophylaxis for hepatic encephalopathy.
The primary ribotypes of C difficile were 001 (30.4%) and 014 (19.6%). Resistance to rifaximin was reported in 30.4% of patients overall and in 84.6% of patients who received rifaximin. In multivariate analysis, the presence of rifaximin-resistant C difficile was associated with ribotype 001 (odds ratio [OR] 42.1, 95% CI, 2.1-828.0; P =.014) and with previous therapy with rifamycin (OR 42.1, 95% CI, 2.1-828.0; P =.014).
The study authors concluded that "[C difficile infection] was mostly due to selection of rifaximin-resistant C difficile strains. Clinicians should be aware of the risk for [C difficile infection] in cirrhotic patients, even in those receiving rifaximin."
Reigadas E, Alcalá L, Gómez J, et al. Breakthrough Clostridium difficile infection in cirrhotic patients receiving rifaximin [published online October 23, 2017]. Clin Infect Dis. doi: 10.1093/cid/cix918