Lower gastrointestinal symptoms and symptoms-based triaging systems are poor predictors of clinical significant disease on colonoscopy.

Introduction: Lower gastrointestinal symptoms (LGS) are a common cause of referral to the gastroenterology service. International guidelines are available to prioritise referrals. Some studies have reported that symptoms alone are a poor marker of clinically significant disease (CSD) but symptoms remain the main way to prioritise referrals in routine clinical practice.

Aims/background: To correlate LGS with colonoscopy findings in an unselected patient cohort and to investigate whether using National Institute for Health and Care Excellence (NICE) guidelines improve risk stratification.

Method: Colonoscopy data over a 2-year period were obtained from our endoscopy database. Only patients with assessment of symptoms as their primary indication for colonoscopy were included. Patient records were retrospectively reviewed. Exclusion criteria: known inflammatory bowel disease (IBD), familial cancer syndromes, polyp and colorectal cancer (CRC) surveillance, and prior colonoscopy within 5 years. Demographics, symptoms and colonoscopy findings were recorded and analysed.

Results: 1116 cases were reviewed; 493 (44%) males, age 54.3 years (16-91). CSD occurred in only 162 (14.5%); CRC 19 (1.7%), high-risk adenoma 40 (3.6%), inflammation 97 (8.7%) (IBD 65 (5.8%), microscopic colitis 9 (0.8%) and indeterminate-inflammation 23 (2%)), angiodysplasia 6 (0.5%). Diarrhoea gave the highest diagnostic yield for CSD of 5.3% (OR 3.15, 95% CI 2.2 to 4.7, p<0.001), followed by PR bleeding, 2.9% (OR 1.9, 95% CI 1.24 to 2.9, p=0.003). Weight loss gave the lowest diagnostic yield of 0.4%; (OR 0.79, 95% CI 0.28 to 2.24, p=0.65). 592 (53%) and 517 (46%) fitted the NICE guidelines for CRC and IBD, respectively. Using NICE positivity improved detection but overall yield remained low 3% vs 0.4% (OR 7.71, 95% CI 1.77 to 33.56, p=0.0064) for CRC, and 9% vs 2.8% (OR 3.5, 95% CI 1.99 to 6.17, p<0.0001) for IBD.

Conclusions: The overall prevalence of CSD in our unselected symptomatic patients is low (14.5%). A holistic approach including combining symptoms and demographics with novel tools including stool biomarkers and minimally invasive colonoscopy alternatives should be applied to avoid unnecessary colonoscopy.