Antibiotic use, previous ED visit raise community-associated C. difficile infection risk
Previous antibiotic use and emergency department (ED) visits are risk factors for acquiring community-associated Clostridium difficile (C. difficile) infections, according to a recent US-based CDC* study.
“[A]ntibiotic use remains a primary risk factor for community-associated C. difficile infection, indicating the critical need for continued efforts to promote outpatient antibiotic stewardship,” said the researchers.
“There’s a lot of work that needs to be done in terms of improving outpatient prescribing practices and making sure that providers are appropriately prescribing antibiotics,” said study author Dr Alice Y. Guh from the CDC, Atlanta, Georgia, US.
Exposure to antibiotics in the 12 weeks prior to illness onset was associated with an increased risk for community-associated C. difficile infection, in particular exposure to cephalosporin (adjusted matched odds ratio [adjOR], 19.02, 95 percent confidence interval [CI], 1.13–321.39; p=0.04), clindamycin (adjOR, 35.31, 95 percent CI, 4.01–311.14; p=0.001), fluoroquinolone (adjOR, 30.71, 95 percent CI, 2.77–340.05; p=0.005), and beta-lactam and/or beta-lactamase inhibitor combination (adjOR, 9.87, 95 percent CI, 2.76–340.05; p=0.0004). [Open Forum Infect Dis 2017;doi:10.1093/ofid/ofx171]
Individuals treated at an ED in the 12 weeks preceding illness onset also had an increased risk for community-associated C. difficile infection (adjOR, 17.37; p=0.01), as did individuals with cardiac disease (adjOR, 4.87; p=0.03), chronic kidney disease (adjOR, 12.12; p=0.03), and inflammatory bowel disease (adjOR, 5.13; p=0.02).
“[R]eceipt of care in an ED within the previous 12 weeks was … significantly associated with [community-associated C. difficile infection], independent of the receipt of antibiotics, suggesting that the ED environment might be a reservoir for C. difficile infection,” said the researchers.
“Compared with other outpatient settings, EDs might handle a higher volume of patient visits, including the potential for more encounters with symptomatic C. difficile infection patients with increased environmental shedding [and] have more frequent patient turnovers which limits the ability to perform environmental cleaning and disinfection between patients. [T]hey might [also] be an important amplifier of C. difficile transmission in [the hospital and community],” they said.
In this 10-site study, patients aged ≥18 years with no history of C. difficile infection who tested positive for C. difficile in the outpatient setting or within 3 days of hospitalization (n=226) were each matched with a C. difficile-negative control (n=226). Patients were limited to those with evidence of diarrhoea (≥3 watery stools over a 24-hour period) following the positive test, while patients and controls with overnight stay in a healthcare facility up to 12 weeks prior were excluded.
More patients than matched controls presented at outpatient settings and EDs in the 12 weeks before illness onset (82.1 percent vs 57.9 percent and 11.2 percent vs 1.4 percent, respectively; p<0.0001 for each comparison).
Patients were also more likely than controls to be exposed to antibiotics in the 12 weeks preceding illness onset (62.2 percent vs 10.3 percent; p<0.0001), as well as have prior exposure to proton pump inhibitors (28.8 percent vs 16.5 percent; p=0.004) or antidepressants (29.3 percent vs 16.8 percent; p=0.002), though increased exposure to the latter two had no impact on C. difficile infection in this study.
As there were patients who had neither antibiotic nor outpatient care exposure prior to illness, the researchers recommended further investigation into identifying other factors that may contribute to C. difficile infection.