A decade of Clostridioides difficile infection: a constant challenge to maintain the status quo.

Introduction: Clostridioides difficile infection (CDI) is a leading cause of healthcare-associated (HA) diarrhoea. We retrospectively investigated data from a comprehensive, multidisciplinary C. difficile surveillance programme focusing on hospitalized patients in a tertiary Irish hospital over 10 years.

Methods: Data from 2012 to 2021 were extracted from a centralized database, including patient demographics, admission, case and outbreak details, ribotypes (RTs), and (since 2016) antimicrobial exposures and CDI treatments. Counts of CDI by origin of infection were explored using ꭓ analyses, Poisson regression was used to investigate trends in rates of CDI and possible risk factors. Time to recurrent CDI was examined by a Cox proportional hazards regression.

Results: Over 10 years, 954 CDI patients had a 9% recurrent CDI rate. CDI testing requests occurred in only 22% of patients. Most CDIs were HA (82.2%) and affected females (odds ratio: 2.3, P<0.01). Fidaxomicin significantly reduced the hazard ratio of time to recurrent CDI. No trends in HA-CDI incidence were observed despite key time-point events and increasing hospital activity. In 2021, community-associated (CA)-CDI increased. RTs did not differ for HA versus CA for the most common RTs (014, 078, 005 and 015). Average length-of-stay differed significantly between HA (67.1 days) and CA (14.6 days) CDI.

Conclusion: HA-CDI rates remained unchanged despite key events and increased hospital activity, whereas by 2021, CA-CDI was at its highest in a decade. The convergence of CA and HA RTs, and the proportion of CA-CDI, question the relevance of current case definitions when increasingly patients receive hospital care without an overnight hospital stay.