Background and aims:Capsule endoscopy is an extended tool for the diagnosis of small bowel Crohn's disease. However, factors associated with positive findings of this technique have not been well established. Our aim is to asses which factors are associated with a better diagnostic yield of capsule endoscopy in suspected small bowel Crohn's disease.Material and methods: This was a retrospective study including patients under capsule endoscopy because of suspected small bowel Crohn's disease. Demographic data of these patients, as well as symptoms and laboratory data including hemoglobin levels, count of leucocytes and platelets, and levels of C-reactive protein, erythrocyte sedimentation rate and fecal calprotectin were collected. Capsule endoscopy studies were classified as negative (no lesions) or positive (lesions suggestive of Crohn's disease). Descriptive, univariate and multivariate analysis were done, as well as diagnostic yield tests of the different markers for predicting lesions in capsule studies.Results: One hundred and twenty-four patients were included (85 women and 39 men). The average age was 38.21 years. Levels of C-reactive protein and fecal calprotectin were the markers more frequently associated with positive findings in capsule endoscopy. Calprotectin presented the best sensitivity as isolated marker. The association of altered levels of C-reactive protein and calprotectin showed the best specificity and predictive values.Conclusions: C-reactive protein and fecal calprotectin are appropriate biomarkers for selecting patients with suspected Crohn's disease of the small bowel for capsule endoscopy studies.