Clostridioides difficile (C difficile) screening in all ICU admissions identified asymptomatic carriers and their risk for developing and/or transmitting infection.
This article was originally published by Contagion Live®. It has been lightly edited.
Clostridioides difficile infection (CDI) screenings among all patients admitted to an intensive care unit (ICU) revealed that asymptomatic carriers are at greater risk of developing infection than in transmitting to other patients, according to a study published in Nature Medicine.
Although conducting such surveillance may counter the preference of hospitals to minimize their ranking on this metric, the investigators suggest that their findings can inform strategies to reduce CDI, the leading health care-associated infection in the United States.
“Current prevention strategies are limited by their failure to account for patients who carry CDI asymptomatically, who may act as hidden reservoirs transmitting infections to other patients,” Arianna Miles-Jay, PhD, and colleagues commented. “To make further gains in reducing rates of CDI, it is necessary to better understand the sources of C difficile beyond cases with CDI within the hospital.”
To improve understanding of the role of asymptomatic carriers, the investigators conducted admission and daily longitudinal culture-based screening for CDI in an ICU over 9 months, performing whole-genome sequencing on all recovered isolates, and applying epidemiological tracking of CDI importation and acquisition during hospitalizations.
Approximately 4000 rectal swab and stool samples from 1289 ICU admissions of 1111 patients yielded 448 CDI isolates, with 425 successfully whole-genomic sequenced. The investigators noted a high exposure to antibiotics (71.8%) during ICU admission, with most admitted through the emergency medicine department.
Multiple strains of CDI were often present in a single patient. Among 80 admissions with at least two CDI isolates and sequence-typed genomes, 13 (15%) included multiple strain types: 7 with at least 2 different toxigenic strains, 5 with a mix of toxigenic and non-toxigenic strains, and 1 with at least 2 different non-toxigenic strains.
Seeking to ascertain whether harboring a non-toxigenic strain protected against acquiring a toxigenic strain, the investigators determined that among 584 admissions qualifying for that analysis, 4 of 27 (14.8%) with non-toxigenic strains subsequently acquired a toxigenic strain, compared to 28 acquisitions among 557 individuals (5.0%) with no CDI detected on admission.
“Our data do not support non-toxigenic CDI as protecting against colonization with toxigenic strains,” Miles-Jay and colleagues observed. "Instead, they indicate that presence of non-toxigenic strains may be a marker of a gut environment conducive to toxigenic CDI acquisition.”
The investigators reported that despite a high burden of carriage, with 9.3% of admissions having toxigenic CDI detected in at least 1 sample, only 1% of patients with negative culture on admission subsequently acquired CDI via cross-transmission.
“While patients who carried toxigenic CDI on admission posed minimal risk to others, they themselves had a 24 times greater risk for developing a healthcare-onset CDI infection than noncarriers,” Miles-Jay and colleagues reported.
They suggest that current infection prevention practices can be effective in preventing nosocomial cross-transmission of CDI, but that additional progress will require better targeting of the transition from asymptomatic carriage to infection.
Reference
Miles-Jay, A., Snitkin, E.S., Lin, M.Y. et al. Longitudinal genomic surveillance of carriage and transmission of Clostridioides difficile in an intensive care unit. Nat Med (2023). doi:10.1038/s41591-023-02549-4
Persistence Pays Off With Zanubrutinib: A Challenging CLL Case With a Prior BTK Inhibitor Failure
May 10th 2024The case of a 77-year-old woman with a long chronic lymphocytic leukemia (CLL) history illustrates the novel use of zanubrutinib as a potential option for some patients who have failed first-generation Bruton tyrosine kinase (BTK) inhibitors and venetoclax.
Read More
Frameworks for Advancing Health Equity: Urban Health Outreach
May 9th 2024In the series debut episode of "Frameworks for Advancing Health Equity," Mary Sligh, CRNP, and Chelsea Chappars, of Allegheny Health Network, explain how the Urban Health Outreach program aims to improve health equity for individuals experiencing homelessness.
Listen
Posters Characterize DMD Caregiver Experiences, Impact of Gene Therapy on Caregiving Demands
May 10th 2024Posters presented at the ISPOR—The Professional Society for Health Economics and Outcomes Research meeting explored Duchenne muscular dystrophy (DMD) caregiver experiences and gene therapy’s impact on work opportunities for caregivers.
Read More