High morbidity and mortality of Clostridium difficile infection and its associations with ribotype 002 in Hong Kong.

<bold>Objectives: </bold>We aim to study the disease burden, risk factors and severity of Clostridium difficile infection (CDI) in Hong Kong.<bold>Methods: </bold>We conducted a prospective, case-control study in three acute-care hospitals in Hong Kong. Adult inpatients who developed CDI diarrhoea confirmed by PCR (n = 139) were compared with the non-CDI controls (n = 114). Ribotyping of isolates and antimicrobial susceptibility testing were performed.<bold>Results: </bold>The estimated crude annual incidence of CDI was 23-33/100,000 population, and 133-207/100,000 population among those aged ≥65 years. The mean age of CDI patients was 71.5. Nursing home care, recent hospitalization, antibiotics exposure (adjusted OR 3.0, 95% CI 1.3-7.1) and proton-pump inhibitors use (adjusted OR 2.2, 95% CI 1.2-3.9) were risk factors. Severe CDI occurred in 41.7%. Overall mortality was 16.5% (among severe CDI, 26.5%). The commonest ribotypes were 002 (22.8%), 014 (14.1%), 012 and 046; ribotype 027 was absent. Ribotype 002 was associated with fluoroquinolone resistance and higher mortality (47.6% vs. 12.7%; adjusted HR 2.8, 95% CI 1.1-7.0).<bold>Conclusions: </bold>Our findings show high morbidity and mortality of CDI in the older adults, and identify ribotype 002 as a possible virulent strain causing serious infections in this cohort. [ABSTRACT FROM AUTHOR]