Background It has been recognized for a long time that about 60% of all spondyloarthritis (SpA) patients show microscopic inflammatory gut lesions, a fraction of which evolves into Crohn’s disease (1). However, since the first publications of these findings (1984-1985), the field of SpA has experienced major developments, among them the possibility to decrease the gap between onset of symptoms and diagnosis, particularly by the introduction of MRI of the sacroiliac joints. As a consequence of the introduction of the new ASAS classification criteria (2), it is now possible to identify early in the disease course patients with non-radiographic axial SpA (nr-axSpA). Additionally, the prevalence of reactive arthritis caused by acute bacterial infections has remarkably decreased over time, suggesting that the prevalence of mucosal inflammation may have declined.
Objectives Our study was designed to ascertain whether the prevalence of gut involvement in SpA has changed and to compare its frequency between patients with early nr-axSpA versus more established diseases, such as ankylosing spondylitis (AS).
Methods The Gent Inflammatory Arthritis and spoNdylitis cohorT (GIANT) is a prospective observational cohort in which patients diagnosed with axial and peripheral SpA according to the ASAS criteria are prospectively followed; at present 110 SpA patients have been included. Ileocolonoscopy was performed in 58 patients (28 men and 30 women), never being treated with TNF blockers. None of the patients reported suggestive gastrointestinal complaints for, or had a previous diagnosis of inflammatory bowel disease. Mean age was 36.6 years. Median symptom duration at the time of the ileocolonoscopy was 5 years. Sixty-nine percent of the patients were HLA-B27 positive.
Results A normal gut histology was found in 51.7% of all patients, 22.4% patients showed acute lesions and in 25.9% chronic lesions were found. Men and women were equally affected. A similar prevalence was noted in nr-axSpA, established AS and peripheral SpA. Chronic gut lesions occurred in 37.5% of patients with a short symtom duration (<2 years) versus 17.6% in patients with longer symptom duration.
Conclusions Microscopic gut inflammation frequently occurs both in early and established axial SpA as well as peripheral SpA, suggesting that gut inflammation is inherent to the SpA disease concept. The observed prevalence is comparable to the prevalence 2 decades ago.
Mielants H, Veys EM, Cuvelier C, et al. The evolution of spondylarthropathies in relation to gut histology. II. Histological aspects. J. Rheumatol. 1995;22(12):2273-8.
Sieper J, Rudwaleit M, Baraliakos X, et al. The Assessment of SpondyloArthritis international Society (ASAS) handbook: a guide to assess spondyloarthritis. Ann Rheum Dis 2009;68(Suppl 2):ii1-ii44.
Disclosure of Interest None Declared