Rare occurrence of inflammatory bowel disease in a cohort of Han Chinese ankylosing spondylitis patients- a single institute study.

Despite a high prevalence of ankylosing spondylitis (AS) in Han Chinese, the clinical experience remains very limited in the extra-articular presentation of inflammatory bowel disease (IBD). A monocentric retrospective study was performed for the AS-associated IBD manifestation. This study analyzed AS patients fulfilling the 1984 revised New York diagnostic criteria, excluding those who had the onset of IBD before or concurrently with the diagnosis of AS, for their demographic, clinical, laboratory, radiological, pathological and medication data, particularly in the usage of anti-TNF monoclonal antibody. Among 988 AS patients with 19.8% female, 4 (0.4%) had the overt IBD presentation, one female and 3 male aged 28 to 47 years (38.8 ± 4.6), all ulcerative colitis with the characteristic histopathological findings. At the onset of colitis, all had a long-term disease duration of 10 to 25 years (17.5 ± 6.5) and high BASDAI 7.5 to 8.8 (8.2 ± 0.5) with the hip joint involvement. There were recurrent flares of colitis despite the treatment with corticosteroids and messalazopyrin/salazopyrin, and no relapses of IBD were observed for 6.0 ± 1.1 years after the adalimumab (ADA) therapy. In this retrospective cohort, we demonstrate the rarity of AS-associated IBD manifestation in Han Chinese with a beneficent effect from the ADA therapy.