Gut inflammation in children with late onset pauciarticular juvenile chronic arthritis and evolution to adult spondyloarthropathy--a prospective study.

Ileocolonoscopy with biopsy of the colon and terminal ileum was performed prospectively on 12 patients under age 16 with late onset juvenile chronic arthritis (JCA). Inflammatory gut lesions were seen in 9 of these 12 patients; 4 were of the acute type, 5 of the chronic type. Chronic gut inflammation was related to axial inflammatory complaints, inflammatory serum variables, thrombocytosis and sacroiliac radiological abnormalities. A 2nd ileocolonoscopy was performed on 5 of the 12 patients, and a 3rd ileocolonoscopy on 2 of these with persistent synovitis. Gut inflammation and joint inflammation were related; moreover, all 5 patients had chronic inflammatory lesions by the time of the last investigation, one presented with Crohn's disease. The 12 patients were reviewed 3 to 9 years after the first ileocolonoscopy. Four patients were in remission, including the 3 patients with initial normal gut histology. Five patients had developed ankylosing spondylitis (AS), a 6th patient possible AS. Axial inflammatory complaints, a family history of spondyloarthropathies, HLA-B27 positivity, early sacroiliac and peripheral joints radiographic changes, persistence of inflammatory serum variables, thrombocytosis and chronic inflammatory lesions on gut biopsy, are predictive factors in juveniles for evolution to AS. Late onset pauciarticular JCA represents a form of spondyloarthropathy similar to adolescent forms. Persistent gut inflammation could play a role in the pathogenesis of the disease and persistent synovitis.