Infection-related hospitalizations in the first year after inflammatory bowel disease diagnosis

With the rapid increase in the incidence of inflammatory bowel disease (IBD) in Asia, the natural course of the early phase of disease in these patients remains poorly defined. This study aimed to determined the incidence and characteristics of infection-related hospitalization in the first year in patients newly diagnosed with IBD in Hong Kong SAR, China.

Patients newly diagnosed with IBD and enrolled in the territory-wide Hong Kong IBD Registry were identified. Details of their hospitalization within the first 12 months after diagnosis were retrieved and analyzed.

Altogether 433 newly diagnosed IBD patients were enrolled, including 188 with Crohn's disease (CD), 230 with ulcerative colitis (UC) and 15 with IBD-unclassified (IBD-U). Among them, 110 (25.4%) had at least one unscheduled hospitalization in the first year and 34 (7.9%) had infection-related hospitalization, leading to 43 (23.4%) of total hospitalizations. Gastrointestinal tract (30.2%), respiratory tract (34.9%) and skin and soft tissues (11.6%) were the most common sites of infection. Bacterial and viral infections accounted for 46.7% and 20.8% of hospitalizations for infection, respectively. Common identified pathogens included Clostridium difficile (16.3%) and Cytomegalovirus (11.6%). Multivariate analysis found that patient's age (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.06) and the presence of comorbidity (OR 2.32, 95% CI 1.05-5.13) were significantly associated with hospitalization from infection in IBD patients.

Infection-related hospitalizations were found in 7.9% of newly diagnosed IBD patients within the first year after diagnosis in Hong Kong, which accounted for about one-quarter of all unscheduled hospitalizations. Elder patients with concurrent illnesses were at higher risk.