Supercrescimento bacteriano de intestino delgado em pacientes com doença de Crohn: prevalência, preditores e associação com inflamação sistêmica e intestinal

Abstract

Introduction: The small intestine bacterial overgrowth (SIBO) is defined as an increase in the number and/or change in the type of bacteria in the small intestine. In its pathogenesis it is important the damage on the ileocecal valve and anatomical abnormalities, both common in Crohn's disease (CD). The aim of this study was to determine the prevalence and predictors of SIBO in CD patients as well as to assess the relationship between SIBO and systemic and/or intestinal inflammation. In this cross-sectional study, between June 2013 and January 2015, 92 CD patients and 97 controls with non-chronic gastrointestinal complaints were assessed for presence of SIBO using the H2/CH4 glucose breath test. Multivariate logistic regression was performed to investigate the potential association between SIBO and demographic, disease-related data, systemic markers of inflammation (C-reactive protein and erythrocyte sedimentation rate), and biomarker of intestinal inflammation (fecal calprotectin concentration - FCC). The SIBO rate was significantly higher in CD patients than in the controls (32.6% vs. 12.4%, respectively, P=0.0008). Patients with and without SIBO were comparable according to demographics, systemic inflammatory biomarkers, and disease characteristics, except to the stricturing phenotype more common in the SIBO-positive CD patients (43.3% vs. 19.3%, P=0.015). Notably, FCC was significantly higher in SIBO-positive patients (median of 485.8 vs.132.7 μg/g; P = 0.004). Patients presenting increased FCC and stricturing disease had an odds of 9.43 (95% CI, 3.04-11.31; P <0.0001) and 3.83 (95% CI, 1.54-6.75; P=0.025) respectively, for SIBO diagnosis. Conclusions: In CD patients, SIBO is a highly prevalent condition. Stricturing phenotype and increased FCC were strongly and independently associated with the presence of SIBO. SIBO diagnostic work-up followed by directed treatment is recommended in CD patients, especially if stricturing disease or concurrent intestinal inflammation is present.