Prevalence of organic disease at colonoscopy in patients with symptoms compatible with irritable bowel syndrome: cross-sectional survey.

OBJECTIVE: Guidelines for the management of irritable bowel syndrome (IBS) encourage a positive diagnosis, but some evidence suggests organic disease may be missed unless investigations are performed. We examined yield of colonoscopy in a cohort of secondary care patients meeting criteria for IBS. MATERIALS AND METHODS: Demographic data, symptoms and findings at colonoscopy were recorded prospectively in consecutive, unselected adults with gastrointestinal (GI) symptoms compatible with IBS according to the Rome III criteria. Prevalence of organic GI disease was compared between those meeting criteria for IBS, according to the presence or absence of co-existent alarm features, and by IBS subtype. RESULTS: A total of 559 patients met Rome III criteria for IBS, of whom 423 reported ≥1 alarm feature and 136 none. There was a significantly higher prevalence of organic GI disease among those reporting alarm features (117 [27.7%]), compared with those without (21 [15.4%]) (p = 0.002). In the latter group of 136 patients, Crohn's disease was the commonest finding (10 [7.4%] subjects), followed by coeliac disease (4 [2.9%] subjects), and microscopic colitis (3 [2.2%] subjects). Regardless of presence or absence of alarm features, patients with constipation-predominant IBS were less likely to exhibit organic GI disease than those with diarrhea-predominant or mixed IBS (12.7% vs. 32.1% and 23.8%, p = 0.006). CONCLUSIONS: One in six patients with symptoms compatible with IBS without alarm features in this selected group exhibited organic GI disease following investigation. Assessment of alarm features in a comprehensive history is vital to reduce diagnostic uncertainty that can surround IBS.

The Rome III criteria for the diagnosis of functional dyspepsia in secondary care are not superior to previous definitions.

BACKGROUND & AIMS: Although the Rome III criteria for functional dyspepsia were defined 7 years ago, they have yet to be validated in a rigorous study. We addressed this issue in a secondary-care population. METHODS: We analyzed complete symptom, upper gastrointestinal (GI) endoscopy, and histology data from 1452 consecutive adult patients with GI symptoms at 2 hospitals in Hamilton, Ontario, Canada. Assessors were blinded to symptom status. Individuals with normal upper GI endoscopy and histopathology findings from analyses of biopsy specimens were classified as having no organic GI disease. The reference standard used to define the presence of true functional dyspepsia was epigastric pain, early satiety or postprandial fullness, and no organic GI disease. Sensitivity, specificity, and positive and negative likelihood ratios (LRs), with 95% confidence intervals (CIs), were calculated. RESULTS: Of the 1452 patients, 722 (49.7%) met the Rome III criteria for functional dyspepsia. Endoscopy showed organic GI disease in 170 patients (23.5%) who met the Rome III criteria. The Rome III criteria identified patients with functional dyspepsia with 60.7% sensitivity, 68.7% specificity, a positive LR of 1.94 (95% CI, 1.69-2.22), and a negative LR of 0.57 (95% CI, 0.52-0.63). In contrast, the Rome II criteria identified patients with functional dyspepsia with 71.4% sensitivity, 55.6% specificity, a positive LR of 1.61 (95% CI, 1.45-1.78), and a negative LR of 0.51 (95% CI, 0.45-0.58). The area under a receiver operating characteristics curves did not differ significantly for any of the diagnostic criteria for functional dyspepsia. CONCLUSIONS: In a validation study of 1452 patients with GI symptoms, the Rome III criteria performed only modestly in identifying those with functional dyspepsia, and were not significantly superior to previous definitions.

Validation of the Rome III criteria for the diagnosis of irritable bowel syndrome in secondary care.

BACKGROUND & AIMS: There are few validation studies of existing diagnostic criteria for irritable bowel syndrome (IBS). We conducted a validation study of the Rome and Manning criteria in secondary care. METHODS: We collected complete symptom, colonoscopy, and histology data from 1848 consecutive adult patients with gastrointestinal symptoms at 2 hospitals in Hamilton, Ontario; the subjects then underwent colonoscopy. Assessors were blinded to symptom status. Individuals with normal colonoscopy and histopathology results, and no evidence of celiac disease, were classified as having no organic gastrointestinal disease. The reference standard used to define the presence of true IBS was lower abdominal pain or discomfort in association with a change in bowel habit and no organic gastrointestinal disease. Sensitivity, specificity, and positive and negative likelihood ratios, with 95% confidence intervals, were calculated for each diagnostic criteria. RESULTS: In identifying patients with IBS, sensitivities of the criteria ranged from 61.9% (Manning) to 95.8% (Rome I), and specificities from 70.6% (Rome I) to 81.8% (Manning). Positive likelihood ratios ranged from 3.19 (Rome II) to 3.39 (Manning), and negative likelihood ratios from 0.06 (Rome I) to 0.47 (Manning). The level of agreement between diagnostic criteria was greatest for Rome I and Rome II (κ = 0.95), and lowest for Manning and Rome III (κ = 0.59). CONCLUSIONS: Existing diagnostic criteria perform modestly in distinguishing IBS from organic disease. There appears to be little difference in terms of accuracy. More accurate ways of diagnosing IBS, avoiding the need for investigation, are required.