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Gastrointestinal Disease:
Overview, Diagnosis, and Treatment

About Gastrointestinal Disease

Abdominal pain, chronic diarrhea, iron-deficiency anemia, and other malabsorption symptoms1,2 are just some of the many symptoms that can make differentiating between gastrointestinal (GI) conditions difficult and frustrating for you and your patients. Such is the case with celiac disease (CD), inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS). Diagnosing these diseases can be particularly challenging because they often target the same organ, the bowel.1 Laboratory investigations can be used to diagnose patients with GI symptoms easier, potentially reducing time to diagnosis and therefore the risk of long-term complication for your patient.


The GI challenge 

IBS, GI cancers, CD, and IBD can all present with varying patterns of similar gastrointestinal symptoms.

Types of GI Disorders

CD (also called gluten-sensitive enteropathy or non-tropical sprue) is an autoimmune disorder of the small intestine that manifests itself when patients consume foods containing gluten.3

IBD are a group of chronic inflammatory disorders of the GI tract. Most notable among this group are Crohn’s disease (CrD) and ulcerative colitis.4

IBS is a chronic, relapsing and often lifelong disorder with medically unexplained symptoms. IBS is the most common functional GI disorder.5

GI Cancer is the fourth most common cause of cancer-related death in the world, and it remains difficult to cure in Western countries, primarily because most patients present with advanced disease.6

Following your clinical history, there are many investigations you can use to help diagnose patients with gastrointestinal symptoms easier.

Gastrointestinal disease: Refining differential diagnosis through testing   

Following your clinical history, there are many investigations you can use to help diagnose patients with GI symptoms easier. These include:

  • Serological investigations
  • Stool investigations
  • Imaging procedures
  • Endoscopic procedures
  • Biopsies

The potential for GI cancer should prompt referral to secondary care in patients that present the following red flag symptoms:

  • Abdominal masses
  • A family history of ovarian cancer
  • Rectal masses
  • Anemia
  • Rectal bleeding
  • Unintentional and unexplained weight loss
  • A family history of bowel cancer
  • Aged >60 years change in bowel habit lasting >6 weeks9

Following clinical history, in the case of recurrent lower-GI symptoms when you have no clinical suspicion of GI cancer, first line serological or stool-based tests are used to rule out more serious conditions and/or determine the need for further investigations.10-13

Diagnosis of Gastrointestinal Conditions3,7,8

Adapted from Husby, et al 2012, Werkstetter et al., 2017, and World Health Organization, 2015. Please be aware that additional analytical parameters can be necessary.

Gluten-related disorders (GRDS)

Even though CD is one of the most common lifelong autoimmune disorders in the world, correct diagnosis rates are surprisingly low.14 This can be attributed to CD’s atypical clinical presentation, as well as its shared characteristics with other GRDs.15

GRDs cover a broad spectrum of diseases triggered by gluten including CD non-celiac gluten sensitivity (NCGS), gluten ataxia, dermatitis herpetiformis (DH) or wheat allergy. NCGS can be used to describe patients who may experience symptoms similar to CD because their bodies do not tolerate gluten. However, NCGS does not cause the same extreme bodily response and intestinal damage that CD does.16

Misdiagnosis when differentiating between GI disorders is common due to similar symptoms, especially as CD can also present with osteoporosis, malabsorption symptoms, sterility, and poliabortivity.10,11,17,18

When left untreated, patients with CD are at risk for serious long-term complications, such as autoimmune disease, osteoporosis, and even certain cancers.19,20

Differentiating between GI conditions

Differentiating between GI conditions, the symptoms of which are very similar, can be difficult and frustrating for both patients and healthcare providers. However, serological testing can be used to help differentiate between GI conditions, potentially reducing the time to diagnosis.12,13,15,17,21-23

These tests can be used to help support the ruling in or ruling out of possible conditions, confirm the presence of inflammation, and help differentiate diseases. 


Testing Confidence

Testing Increases Diagnostic Confidence

Adding diagnostic testing to aid in a differential diagnosis has been shown to increase confidence in diagnosis to 90 percent.i,ii Conventionally, a diagnosis of allergic or autoimmune disease relies on the case history and a physical examination. However, adding diagnostic testing to aid in a differential diagnosis has been shown to increase confidence in diagnosis.i,ii Diagnostic testing can also help to improve the patient’s quality of life and productivity, reduce costs associated with absenteeism, and optimize use of medication, in addition to decreasing unscheduled healthcare visits.iii,iv 

i. Duran-Tauleria E, Vignati G, Guedan MJ, et al. The utility of specific immunoglobulin E measurements in primary care. Allergy. 2004;59 (Suppl78):35-41.
ii. NiggemannB, Nilsson M, Friedrichs F. Paediatric allergy diagnosis in primary care is improved by in vitro allergen specific IgE testing. Pediatr Allergy Immunol. 2008;19:325-331
iii. Welsh N, et al. The Benefits of Specific Immunoglobulin E Testing in the Primary Care Setting. J Am Pharm Assoc. 2006;46:627.
iv. Szeinbach SL, Williams B, Muntendam P, et al. Identification of allergic disease among users of antihistamines. J Manag Care Pharm. 2004; 10 (3): 234-238

Learn about autoimmune disease.

Learn more about testing.

Management and care of patients with gastrointestinal disease

Gastrointestinal (GI) diseases exact heavy social costs, which are associated with losses in productivity caused by lost or impaired ability to work, as well as the intangible costs of pain and suffering. It’s clear that GI diseases impose a significant impact on quality of life, particularly for patients with chronic issues.24,25 Designing a treatment strategy based on severity of symptoms includes dietary modification, pharmacotherapy, and behavioral or psychological therapy. These should be tailored to the symptoms and individual patient preferences, and integrated when necessary.26

Disease management and treatment is tailored to the specific GI disease and can vary based on disease and severity.24,25

  1. PasculV, Dieli-Crimi R, López-Palacios N, et al. Inflammatory bowel disease and celiac disease: Overlaps and differences. World J Gastroenterol. 2014;20(17):4846-4856. 
  2. Gujral N, Freeman HJ, Thomson A. Celiac disease: Prevalence, diagnosis, pathogenesis and treatment. World J Gastroenterol. 2012;18(42):6036-6059.
  3. Husby S, Koletzko S, Korponay-Szabó IR, et al. European Society for Pediatric Gastroenterology, Hepatology, and Nutrition Guidelines for the Diagnosis of Coeliac Disease. J Pediatr Gastroenterol Nutr. 2012;54:136–160. 
  4. Molodecky NA, Soon IS, Rabi DM, et al. Increasing incidence and prevalence of the inflammatory bowel diseases with time, based on systematic review. Gastroenterology. 2012;142(1):46-54.
  5. Harkness EF, Harrington V, Hinder S, et al. GP perspectives of irritable bowel syndrome – an accepted illness, but management deviates from guidelines: a qualitative study. BMC Fam Pract. 2013;14: 92. 
  6. World Health Organization. Cancer: Fact Sheet No 297. WHO. http://www.who.int/mediacentre/factsheets/fs297/en/. Accessed November 2017.
  7. Werkstetter KJ, Korponay-Szabó IR, Popp A, et al. Accuracy in Diagnosis of Celiac Disease Without Biopsies in Clinical Practice. Gastroenterology. 2017;153(4):924-935.
  8. World Gastroenterology Organisation. Inflammatory Bowel Disease Update 2015. http://www.worldgastroenterology.org/guidelines/global-guidelines/inflammatory-bowel-disease-ibd/inflammatory-bowel-disease-ibd-english. Accessed February 2018.
  9. National Institute for Health and Care Excellence. Irritable Bowel Syndrome. June 2015. www.nice.org.uk/guidance/qs114/documents/irritable-bowel-syndrome-in-adults-qs-briefing-paper2. Accessed November 2017
  10. National Institute for Health and Care Excellence. Faecal calprotectin diagnostic tests for inflammatory disease of the bowel (DG11). 2013. https://www.nice.org.uk/guidance/dg11. Accessed November 2017.
  11. National Institute for Health and Care Excellence. NICE pathways – Crohn’s disease. http://pathways.nice.org.uk/pathways/crohns-disease. Accessed November 2017.
  12. National Institute for Health and Care Excellence. NICE pathways – Ulcerative colitis. http://pathways.nice.org.uk/pathways/ulcerative-colitis. Accessed November 2017.
  13. National Institute for Health and Care Excellence. Irritable bowel syndrome in adults (QS114). 2016. London: National Institute for Health and Care Excellence. https://www.nice.org.uk/guidance/cg61/chapter/1-Recommendations#diagnosis-of-ibs. Accessed November 2017.
  14. Lebwohl et al. Coeliac Disease. Lancet. 2018 Jan 6;391(10115):70-81
  15. Picarelli A, Di Tola M, Borghini R, et al. The High Medical Cost of Celiac Disease Missed Diagnosis: Is it Cheaper to Suspect it in Time? Intern Med. 2014;4:155. 
  16. Sapone A, et al. Spectrum of gluten-related disorders: consensus on new nomenclature and classification. BMC Medicine. 2012, 10:13
  17. Beyond Celiac. Celiac Disease Symptom List. https://www.beyondceliac.org/celiac-disease/symptoms/. Accessed November 2017.
  18. Green PH. The many faces of celiac disease: clinical presentation of celiac disease in the adult population. Gastroenterology. 2005;128:S74-78. 
  19. Schuppan D, Zimmer KP. The Diagnosis and Treatment of Celiac Disease. Dtsch Arztebl Int. 2013;110(49):835–846.
  20. Lauret E, Rodrigo L. Celiac disease and autoimmune‐associated conditions. BioMed Research International. 2013;127589. 
  21. Burri E, Beglinger C. Faecal calprotectin -- a useful tool in the management of inflammatory bowel disease. Swiss Med Wkly. 2012;142: w13557.
  22. Schuppan D, Zimmer KP. The Diagnosis and Treatment of Celiac Disease. Dtsch Arztebl Int. 2013;110(49):835–846
  23. Lebwohl et al. Coeliac Disease. Lancet. 2018 Jan 6;391(10115):70-81
  24. Sandler RS et al. The Burden of Selected Digestive Diseases in the United States. Gastroenterology. 2002;122:1500–151.
  25. Peery AF et al. Burden of Gastrointestinal Disease in the United States: 2012 Update. Gastroenterology. 2012; November; 143(5): 1179–1187.e3.
  26. Bharucha AE, Chakraborty S, Sletten CD. Common Functional Gastroenterological Disorders Associated With Abdominal Pain. Mayo Clin Proc. 2016 Aug;91(8):1118-32. doi: 10.1016/j.mayocp.2016.06.003. PMID: 27492916; PMCID: PMC4985027.