Pets may be protective against recurrent C difficile, study finds
In a surprising finding, pet ownership and increasing contact with pets may be protective against the recurrence of community-acquired Clostridiodes difficile infection (CDI), researchers from the University of Pennsylvania reported recently in Open Forum Infectious Diseases.
To investigate whether pet ownership is a risk factor for CDI recurrence, a hypothesis based on documented animal carriage of C difficile and overlap of strains isolated from animals and people, the researchers conducted a case-control study among 86 patients with recurrent CDI (cases) and 146 patients with nonrecurrent CDI (controls).
Study participants were sent a survey to ascertain the number and species of pets in the household at the time of the initial CDI diagnosis, and the degree of contact between patients and pets. Multivariable logistics regression modeling was used to determine the association between recurrence of CDI and pet ownership, while accounting for patient-level risk factors.
The results of the multivariable analysis showed that pet ownership was not significantly associated with CDI recurrence (odds ratio [OR], 1.02; 95% confidence interval [CI], 0.38 to 2.72; P = 0.965) among all 232 patients. Furthermore, when the researchers analyzed a subset of 127 patients with community-associated or community-onset, healthcare-facility–acquired CDI, they found that increasing contact with pets was increasingly protective against recurrence: for every point increase in a pet contact score (out of 7 possible points), the odds of recurrence decreased by 14% (OR, 0.86; 95% CI, 0.74 to 1.00; P = 0.051).
The authors of the study conclude, "Although more research is needed to understand the transmission dynamics of C. difficile within a household and between pets and owners, it appears that pet ownership and close contact with pets are not associated with recurrence of CDI and may instead be protective against recurrence of CDI in patients with community-acquired or community-onset CDI."
Jan 18 Open Forum Infect Dis study
Before-hospital antibiotic exposure may heighten risk of C diff infection
In another study on CDI risk factors, researchers from Intermountain Healthcare and Stanford University found that cumulative antibiotic exposure prior to admission is significantly associated with the risk of subsequent CDI. The findings appeared yesterday in Antimicrobial Agents and Chemotherapy.
For the study, the researchers identified all symptomatic hospital-onset and healthcare-facility–associated, community-onset CDI cases among adults admitted to 21 Intermountain Healthcare hospitals from 2006 through 2012, then evaluated the risk associated with antibiotic exposure, including specific agents administered prior to and during admission, using multivariable logistic regression. While antibiotic use is a known risk factor for CDI, the degree to which various antibiotic classes are associated with CDI risk is not fully understood.
Overall, 2,356 cases of CDI occurred among 506,068 unique admissions, for an incidence rate of 46.6 per 10,000 admissions. After adjusting for demographics and other CDI risk factors, the analysis found that any antibiotic administered prior to admission was the predominant risk factor for CDI, contributing far more risk than antibiotics received during the hospital stay. For every antibiotic day of therapy prior to the index admission, odds of subsequent CDI increased by 12.8% (OR, 1.128; 95% CI, 12.2% to 13.4%; P < 0.0001). Odds of CDI were greatest with second- and third-generation cephalosporins, fluoroquinolones, and clindamycin. Doxycycline and daptomycin were associated with lower CDI risk.
The authors of the study say the data should be taken into consideration by antibiotic stewardship teams for identifying patients at risk for CDI.
Jan 21 Antimicrob Agents Chemother abstract