Background: An increasing number of patients with inflammatory bowel diseases (IBD) are being treated with infliximab in China and are at increased risk of activating tuberculosis infection. Real-world epidemiological data on tuberculosis infection in patients with IBD receiving infliximab are scarce in China, where tuberculosis is endemic. The aim of our study is to investigate the risk of tuberculosis in a large cohort of IBD patients treated with infliximab in China.
Methods: An observational study on all tuberculosis cases identified in IBD patients receiving infliximab was performed in 23 tertiary referral hospitals between 2009 and 2016 in China. Results of tuberculosis screening tests, which included interferon-gamma releasing assay (IGRA), tuberculin skin test (TST), chest X-ray, and computed tomography of the chest, prophylaxis against tuberculosis prior to infliximab therapy, and events of active tuberculosis infection after infliximab therapy were recorded and analyzed.
Results: 1233 IBD patients receiving infliximab were recruited with a median follow up of 13 months (interquartile range [IQR] 6–24). 98% of the patients underwent screening tests prior to infliximab therapy. Screening results suggested the proportion of Chinese IBD patients with latent tuberculosis infection (LTBI) prior to infliximab therapy is 7.22% (89/1233). Twelve cases of active tuberculosis infection occurred after infliximab therapy. The incidence of active tuberculosis infection in Chinese IBD patients receiving infliximab therapy is 746 per 100,000 person-years, which is 9 times higher than that of the general Chinese population (75 per 100,000 person-years). Among IBD patients with LTBI, the incidence of subsequent active tuberculosis after infliximab therapy is 8 times higher than patients without LTBI (5.62% [5/89] versus 0.61% [7/1144], p<0.01). 97% of 89 LTBI patients and 30% of 1144 patients without LTBI received prophylaxis against tuberculosis. After prophylaxis, the incidence of tuberculosis infection didn't decrease in IBD patients without LTBI (0.57% [2/348] versus 0.62% [5/797], p=0.638).
Conclusions: Infliximab therapy increased the incidence of tuberculosis in Chinese IBD patients. Routine prophylaxis may not reduce the risk of active tuberculosis infection in Chinese IBD patients without LTBI. Tuberculosis screening should be strongly recommended in Chinese IBD patients before initiating infliximab therapy.