Chronic intestinal inflammation and seronegative spondyloarthropathy in children

Background. Spondyloarthropathy in adults has been shown to be associated with either clinical or subclinical intestinal inflammation, however this association has rarely been described in children. Aim. To report paediatric patients primarily referred to a paediatric gastroenterology centre for suspected inflammatory bowel disease and found to be affected by a seronegative spondyloarthropathy. Intestinal inflammatory lesions and rheumatological features have been described in them. Subjects. During a 18-month period, 129 children were referred because of symptoms and signs suggesting an inflammatory bowel disease; 31 of them (range age: 5-17 years) were selected because they also had signs of axial and/or peripheral arthropathy and form the basis of our study. Methods. The investigated patients underwent ileo-colonoscopy with biopsy and rheumatological assessment that also included X-ray and magnetic resonance imaging of the sacroiliac joints. Results. Only seven children had a classical inflammatory bowel disease (four had ulcerative colitis, three had Crohn's disease), 12 had an indeterminate colitis, 12 a lymphoid nodular hyperplasia of the distal ileum as main feature. In the latter two groups, endoscopy and histology revealed an intestinal inflammation of chronic type distinct from the classical pattern found in inflammatory bowel disease. All were HLA B27 negative and fulfilled the European Spondyloarthropathy Study Group criteria for spondyloarthropathy (except five children classified as undifferentiated spondyloarthropathy). Conclusions. In a group of children primarily investigated for suspected inflammatory bowel disease and also presenting a seronegative spondyloarthropathy we have described both intestinal and rheumatological features. The majority of them exhibited either an indeterminate colitis or a lymphoid nodular hyperplasia of the distal ileum as main feature. These patients may be a population at risk of developing a full inflammatory bowel disease phenotype.