in contrast , in 30 of 35 ( 56.6 % ) patients with ankylosing spondylitis , and in 37 of 55 ( 67 % ) patients with reactive arthritis , regardless of hla b27 phenotype , there was histological evidence of inflammatory bowel disease with features either of acute enterocolitis , or early crohn 's disease .
C0021390
inflammatory bowel disease
C0010346
crohn 's