Diarrhoea: A Running Commentary Diane O’Meara Physician Associate Digestive Diseases Centre Objectives • Discuss common and sort-of-common causes of (chronic) diarrhoea • Review the standard tests done in GP setting for evaluation of diarrhoea • Discuss what happens after a patient is referred to gastroenterology for investigation of diarrhoea A Few Causes, in no particular order • Medication • Microscopic colitis • Infectious • Bile acid diarrhoea • Coeliac • Small bowel bacterial • IBD overgrowth • Bowel cancer • Pancreatic insufficiency • Diverticular • Lactose malabsorption • Overflow • IBS Definition • A condition in which stool is – more liquid than usual and – is passed more frequently than usual (three or more in a day) • Patients may use a variety of terms – Clotted cream – Liquidy – Fluffy – Wet wind Classification Possible Investigations GP • Standard stool culture – Salmonella, Shigella, Campylobacter, E coli 0157 – C difficile • Ova and Parasites, Giardia and Cryptosporidium • Bloods – FBC, B12, folate, iron studies – Thyroid function – tTG IgA (coeliac) – CRP (IBD) – CA-125 (ovarian cancer) • FIT (if age appropriate) – Measure of occult blood- neoplasm/polyp? • Faecal calprotectin – Measure of inflammation- (IBD?) Parasitic Infection and Chronic Diarrhoea • Recommended to send 3 samples for O&P, 2 days apart • Immunocompromised • Travellers – ‘other than to Western Europe, North America, Australia or New Zealand’ (NICE) Note travel history • On request form for the lab • Where • When (up to 2 years?) • Household contacts travelled?? UHL Coeliac Disease • Immune-mediated Enteropathy (immune system attacking the small bowel) • Precipitated by exposure to dietary gluten Coeliac Disease • 0.7% prevalence in Europe • Diarrhoea may be present in 43-85% of patients • Other signs and symptoms may include abdominal pain, constipation, weight loss, iron/vitamin deficiencies, fatigue, infertility Interactive • A 25 year old woman is seen in the GP surgery for a history of abdominal bloating and diarrhoea. Her brother had similar symptoms and was diagnosed with coeliac and is much better on a gluten free diet. Which is the most appropriate screening test for coeliac disease? – A. Duodenal biopsy – B. Endomysial antibody – C. HLA-DQ2 and HLA-DQ8 – D. Total IgA – E. tTG IgA Interactive • A 25 year old woman is seen in the GP surgery for a history of abdominal bloating and diarrhoea. Her brother had similar symptoms and was diagnosed with coeliac and is much better on a gluten free diet. Which is the most appropriate screening test for coeliac disease? – A. Duodenal biopsy – B. Endomysial antibody – C. HLA-DQ2 and HLA-DQ8 – D. Total IgA – E. tTG IgA Coeliac Disease • tTG IgA (tissue transglutaminase) – Screening test – Lab should check total IgA levels – Must be done on a gluten-containing diet • Endomysial antibody – More expensive – More specific (fewer false positives) than tTG IgA – Less sensitive (more false negatives) than tTG IgA – Must be done on a gluten-containing diet • HLA-DQ2 (85-90%) and HLA-DQ8 (5-10%) – Must carry to have coeliac – Low sensitivity- 40% of population carries it (don’t have to have coeliac if you carry it) – Can be used in patients on a gluten free diet Interactive • Her tTG IgA is 40 U/mL (0-4). What is the next appropriate step? – A. Gluten challenge with 2 pieces of bread a day and recheck tTG IgA in eight weeks to measure change. – B. Keep on current diet and refer to Gastroenterology for OGD with duodenal biopsy. – C. Initiate gluten-free diet and refer to Gastroenterology for OGD with duodenal biopsy. – D. Initiate gluten-free diet and recheck tTG IgA in eight weeks. – E. Metronidazole 500mg bd for 10 days. Interactive • Her tTG IgA is 40 U/mL (0-4). What is the next appropriate step? – A. Gluten challenge with 2 pieces of bread a day and recheck tTG IgA in eight weeks to measure change. – B. Keep on current diet and refer to Gastroenterology for OGD with duodenal biopsy. – C. Initiate gluten-free diet and refer to Gastroenterology for OGD with duodenal biopsy. – D. Initiate gluten-free diet and recheck tTG IgA in eight weeks. – E. Metronidazole 500mg bd for 10 days. Coeliac Disease • Patients with positive tTG IgA must be referred to Gastro for Oesophagogastroduodenoscopy (OGD) with duodenal biopsy. – Gold standard – This is needed to make the diagnosis – Must be done on a gluten-containing diet Coeliac Disease Upper endoscope: used for OGD Endoscopic findings Normal duodenal villi Endoscopic findings • Villous atrophy • Histologic findings: Photo credit Sherif Shabana Intraepithelial lymphocytes, (Friends of Endoscopy Facebook Group) crypt hyperplasia Coeliac disease • Treatment: – Lifelong gluten free diet (dietician) • coeliac.org.uk • Monitor tTG IgA (should return to normal on a 100% gluten free diet) • Other bloods- FBC, haematinics, Vitamin D, calcium, TFTs, LFTs • First degree relatives should be offered screening Faecal calprotectin (FCP) • Measure of intestinal inflammation • Protein (dimer of calcium binding proteins) • High concentration in neutrophil cytoplasm • Resistant to degradation- easy to measure in faeces • Typically used in Inflammatory Bowel Disease (colitis more than small bowel disease) FCP • Results – <30 normal – Up 200 not sure, need to consider other factors – 200 to 1800 not sure, warrants investigation – >1800 strongly considering IBD (or infection) Interactive • A 19 year old man is referred to Gastro outpatients for a six month history of loose stool. He opens his bowels 8 times a day with occasional blood. He has lost approximately one stone (6kg) over this period of time. He complains of joint pains. Faecal calprotectin is >1800. Which is the next most appropriate step? – A. Colonoscopy – B. CT Thorax, abdomen, pelvis – C. OGD with duodenal biopsy – D. Rheumatology referral – E. Soluble fibre (psyllium husk) Interactive • A 19 year old man is referred to Gastro outpatients for a six month history of loose stool. He opens his bowels 8 times a day with occasional blood. He has lost approximately one stone (6kg) over this period of time. He complains of joint pains. Faecal calprotectin is >1800. Which is the next most appropriate step? – A. Colonoscopy – B. CT Thorax, abdomen, pelvis – C. OGD with duodenal biopsy – D. Rheumatology referral – E. Soluble fibre (psyllium husk) Colonoscopy Inflammatory Bowel Disease • Ulcerative Proctitis Inflammatory Bowel Disease • Autoimmune disease • Crohn’s Colitis UK website • Crohn’s disease • Treatment – Small bowel – 5 ASAs – Colon • Mesalasine, Pentasa, – Fistulising Salofalk, Asacol, Octasa • Sulfasalazine (joint • Ulcerative colitis problems) – Proctitis – Immunomodulators – Left/right sided • 6MP, Azathioprine – Pancolitis – Biologics • Infliximab, Adalimumab, • Diagnosed Vedolizumab, – Colonoscopy Ustekinemab, Golimumab – Capsule endoscopy – Steroids • Prednisolone, Budesonide Interactive • A 54 year old man goes to the GP surgery with a 6 week history of loose stool. Prior to this he had a normal bowel habit. He has lost one stone (6kg). Investigations are sent and stool cultures are negative, tTg IgA is <1, thyroid function tests are normal, FBC is normal, FIT is elevated at 300 ng/mL (<10). Which is the next most appropriate test? – A. Colonoscopy on 2WW – B. Faecal calprotectin – C. Flexible sigmoidoscopy on 2WW – D. Referral to dietician – E. Iron studies Interactive • A 54 year old man goes to the GP surgery with a 6 week history of loose stool. Prior to this he had a normal bowel habit. He has lost one stone (6kg). Investigations are sent and stool cultures are negative, tTg IgA is <1, thyroid function tests are normal, FBC is normal, FIT is elevated at 300 ng/mL (<10). Which is the next most appropriate test? – A. Colonoscopy on 2WW – B. Faecal calprotectin – C. Flexible sigmoidoscopy on 2WW – D. Referral to dietician – E. Iron studies Colonoscopy Obstructive diarrhoea CT Colonography https://radiopaedia.org/articles/computed-tomographic-ct- Case courtesy of Dr Dalia Ibrahim, Radiopaedia.org, rID: 28747 colonography Dr Dan J Bell◉ and Dr Dalia Ibrahim et al. FIT (faecal immunochemical test) • Newer test specific for human blood in stool (as opposed to blood from foods eaten) • Rolled out in 2018 • One sample instead of three samples of two • BCSP ages 60 to 74 every other year • May use for over age 50 with unexplained pain/weight loss FIT • Who will have a positive FIT? – Neoplasm – Polyp – Colitis (IBD, ischaemic) – Haemorrhoids • How does diarrhoea fit in? – Obstructive neoplasm – IBD/colitis Interactive • A 30 year old man goes to gastro outpatients for follow up. He has had several normal investigations for diarrhoea including a colonoscopy. He reports feeling better for a few weeks after the colonoscopy but his diarrhoea has returned. He is embarrassed because he is now having accidents. He has been on increasing doses of loperamide, currently taking 16mg a day. Which is the best recommendation? – A. Add macrogol – B. Discontinue loperamide and start macrogol – C. Haemorrhoid suppositories – D. Increase loperamide to 32mg daily – E. Trial a gluten free diet Interactive • A 30 year old man goes to gastro outpatients for follow up. He has had several normal investigations for diarrhoea including a colonoscopy. He reports feeling better for a few weeks after the colonoscopy but his diarrhoea has returned. He is embarrassed because he is now having accidents. He has been on increasing doses of loperamide, currently taking 16mg a day. Which is the best recommendation? – A. Add macrogol – B. Discontinue