Diagnostic value of faecal calprotectin in unselected outpatients referred for colonoscopy: A multicenter prospective study.

OBJECTIVES: To evaluate the role of faecal calprotectin in consecutive outpatients referred for colonoscopy. METHODS: Outpatients undergoing colonoscopy at five participating institutions were eligible. Demographic and clinical data were collected. Faecal samples were tested at a single laboratory by means of a commercially available kit. RESULTS: We consecutively enrolled 870 patients. Mean levels of calprotectin were significantly higher in patients with neoplastic and inflammatory disorders when compared with subjects with a normal colonoscopy or trivial endoscopic findings. Elevated calprotectin levels (>50mg/dl) were detected in 85% of patients with colorectal cancer, and 81% of those with inflammatory conditions but also in 37% of patients with normal or trivial endoscopic findings. In patients referred for chronic diarrhoea, sensitivity and negative predictive value were 100% in detecting either any organic colonic disease. In patients referred for symptoms of "suspected functional origin" sensitivity and negative predictive value for colorectal cancer were also 100%. CONCLUSIONS: In unselected outpatients referred for colonoscopy, a single measurement of faecal calprotectin is not sufficiently accurate to identify those with significant colorectal disease. However, a normal result can help rule out organic disease among patients with diarrhoea and those with abdominal pain and/or constipation.

Angiotensin-converting enzyme insertion/deletion gene polymorphism in inflammatory bowel diseases.

INTRODUCTION: The renin-angiotensin system is strictly related to the kallikrein-kinin system and both are involved in many physiological and disease conditions and possibly in the pathogenesis of inflammatory bowel disease (IBD). Angiotensin-converting enzyme (ACE) is the pivotal enzyme of the renin-angiotensin system and the main catabolic enzyme of the kallikrein-kinin system. The ACE I/D (insertion/deletion) is a polymorphism of the gene encoding for ACE: participants who are homozygous for the D allele exhibit higher ACE levels, which in turn appear to play a deleterious role in several diseases. AIM: To study the prevalence of ACE I/D polymorphism in IBD patients and its possible association with disease features. METHODS: A total of 232 IBD patients, 124 with ulcerative colitis (UC) and 108 with Crohn's disease and 99 healthy controls were genotyped for the ACE I/D polymorphism. RESULTS: DD, ID and II genotypes distribution did not show significant differences between IBD patients and controls: 42.2 vs. 40.4%, 42.7 vs. 47.5% and 15.1 vs. 12.1%, respectively. No significant difference was observed between Crohn's disease and UC patients. Within UC patients, the presence of DD genotype and the carriage of the D allele were significantly associated with the presence of extraintestinal manifestations: odds ratio (OR) 4.08, 95% confidence interval (CI): 1.62-10.28; P<0.003 and OR=3.07, 95% CI: 1.45-6.48; P<0.003, respectively. No significant association was found with other IBD clinical features. CONCLUSIONS: The ACE I/D polymorphism is not associated with IBDs but the D allele appears to increase the risk of developing extraintestinal manifestations in UC patients.