BackgroundSometimes Crohn’s disease (CD) manifests initially with rheumatological symptoms. Therefore, there’s an important for a rheumatologist to recognize this pathology correctly and timely.ObjectivesTo present cases of CD, referred to V.A. Nasonova Research Institute of Rheumatology.MethodsCase series of 7 pts (5 boys, 2 girls) with initial rheumatological condition who developed CD. All pts were subjected to standard rheumatological examination. CD diagnosis was suggested by a rheumatologist and confirmed in gastroenterology hospital.ResultsMean age at CD onset was 12,7±3,98 yrs, varying from 5 to 17 yrs. In 4 pts gastrointestinal (GIT) symptoms manifested simultaneously with rheumatological, in 2 pts GIT symptoms were delayed for 4 and 5 years. The time-interval from the onset of first symptoms until establishing CD diagnosis varied from 2 months till 6 years, averaging to 96± 38 months. The list of initial rheumatological diagnoses included the following entities: juvenile idiopathic arthritis (JIA) with oligoarticular onset – in 5 pts, and systemic onset JIA – in 2 pts. In all cases arthritis manifested initially as an oligo-involvement of a lower limb joints. High active sacroiliitis with deep bone oedema was detected by MRI in 5 pts. Fever was present in 5 pts, uveitis – in 1, cutaneous psoriasis – in 1. Other documented symptoms included: weight loss (3), hepatosplenomegaly (1), lymphadenopathy (1), aphthouse stomatitis (1), nodular erythema (1), erythematous rash (1). HLA B27-antigen positivity was established in 3 pts out of 5 examined. All pts had significant increase in CRP and ESR levels and WBC counts; (additionally 3 examined for calprotectin cases demonstrated significant increase of its’ concentration (>1000 µg/g).ConclusionIBD, including CD, should not be missed and ruled out in all pts with oligoarticular and systemic JIA onset. Fecal calprotectin should be checked in suspected CD cases among individuals with rheumatologic symptoms. Special attention should be given to cases manifesting during puberty, accompanied by weight loss, fever, GIT symptoms, increased levels of acute phase inflammatory markers. MRI stir lesion may be as suspected of IBD especial CD.Disclosure of InterestsNone declared