Coeliac disease - clinical review

Diagnosis and management of coeliac disease, including typical and atypical presentations, prognosis and follow-up.

The only effective treatment for CD is a lifelong GF diet
The only effective treatment for CD is a lifelong GF diet

Section 1: Epidemiology and aetiology
Section 2: Making the diagnosis
Section 3: Managing the condition
Section 4: Prognosis
Section 5: Case study
Section 6: Evidence base


Section 1: Epidemiology and aetiology

Coeliac disease (CD) is a common GI disease characterised by small bowel mucosal injury and nutrient malabsorption in genetically susceptible individuals following dietary ingestion of gluten. Gluten is commonly found in wheat, rye and barley.

Epidemiology

CD was first described by Dr Samuel Gee in 1888.1 The highest prevalence is in Ireland, Finland and countries to which Europeans have emigrated (North America, Australia).

CD is almost unknown in east Asia, where there is a lack of HLA-DR3, DQB1*0201 haplotype. However, the incidence is increasing in Africa (Sahrawi population),2 Asia (India, Pakistan)3 and the Middle East. Prevalence is 0.7-2% in most of these populations.4

The incidence of CD confirmed by biopsy ranges from two to 13 per 100,000 per year.4

The pathogenesis involves interactions between environmental, genetic and immunological factors.5

Proteins in wheat, rye and barley are collectively termed gluten. Wheat contains gliadins and glutenins. Barley and rye have hordeins and secalins that activate disease. The high glutamine and proline content in these proteins may play a key part in disease pathogenesis.6

CD is strongly associated with specific HLA class II genes that map to the DQ locus.7

CD pathogenesis is divided into three major series of events - luminal and early mucosal events, activation of pathogenic CD4+ T cells, and subsequent events leading to tissue damage. Some aspects are well understood, others remain the subject of continuing research.

Classification

The US National Institutes of Health (NIH) consensus classifies CD based on subphenotypes (see box 1).8

Box 1: Classification of CD
Classification Symptoms Diagnoses based on
Classical CD GI symptoms
Complications secondary to malnutrition
Positive serology
Villous atrophy
Symptoms improve on gluten-free (GF) diet
CD with atypical symptoms Extra-intestinal manifestations
Few or no GI symptoms
Positive serology
Villous atrophy
Symptoms improve on GF diet
Silent CD Asymptomatic Positive serology
Villous atrophy
Latent CD Asymptomatic
May develop symptoms or histological changes
Positive serology
No villous atrophy


Section 2: Making the diagnosis

No single test will establish the diagnosis. It is important to recognise the clinical features (see box 2); these and the laboratory findings may establish the diagnosis. All tests should be performed on a gluten-rich diet.

Box 2: Clinical features
Typical presentations
  • Chronic diarrhoea (<50% of patients at presentation)13
  • Weight loss (but at least 30% overweight at presentation)14
  • Abdominal pain and bloating (patients satisfying Rome II criteria have 5% risk for undiagnosed CD)15
  • Failure to thrive and protein energy malnutrition (mainly in children)
  • Spectrum of presentation varies from severe protein energy malnutrition to mild abdominal symptoms. Non-diarrhoea predominant and silent CD presentations more frequent
Atypical presentations
  • Iron and folate deficiency +/- anaemia (may occur in isolation)
  • Low vitamin B12 levels (about 12% have deficiency)16
  • Recognition of signs of villous atrophy at endoscopy13
  • Screening high-risk groups, especially relatives of patients with CD
  • Sensory peripheral neuropathy and ataxia17
  • Infertility in women (not all have positive serology)18,19
  • High amylase20
  • Isolated hypertransaminasaemia
  • Hypoalbuminaemia
  • Raised ESR
  • Dermatitis herpetiformis

Coeliac serology

Coeliac serology, the first step in diagnosis, involves IgA antihuman tissue transglutaminase (TTG) and IgA endomysial antibody immunofluorescence (EMA) tests. The sensitivity and specificity of EMA and TTG have been estimated as >95% and close to 100%, respectively.9

Endoscopy and biopsies

Endoscopy without biopsies is inadequate. If clinical suspicion is high, gastroscopy and duodenal biopsy should be performed, even if serology is negative.10,11 A presumptive diagnosis can be made with positive serology and suggestive biopsies, but this is confirmed when symptoms resolve on a GF diet.

Genetic testing

If there is diagnostic uncertainty, HLA haplotype testing can be useful. More than 95% of affected patients have DQ2 (HLA-DQA1*05-DQB1*02) or DQ8 (HLADQA1*03-DQB1*0302), compared with 40% in the general population. CD is extremely unlikely if HLA-DQ2 or DQ8 is negative.12

Gluten challenge is rare; its most likely scenario is in patients who are on a GF diet despite not having been diagnosed with CD.

In patients with suggestive symptoms and negative serology, it is important to consider selective IgA deficiency and perform an IgG-TTG or IgG-EMA test, or genotyping.


Section 3: Managing the condition

Treatment of CD should be started only after a complete diagnostic evaluation. There is no currently available medication that can safely prevent the mucosal damage that occurs due to gluten exposure.

Gluten-free diet

The only effective treatment is a lifelong GF diet. It is impossible to exclude all gluten, so for practical purposes, 'gluten-free' is minimal gluten that is harmless to the gut.

The Codex Alimentarius defines GF foods as having less than 20ppm of gluten. The 'safe' limit is likely to be about 10mg per day but anecdotal reports suggest some patients may be sensitive even to this amount.

The NIH consensus statement lists six key elements in the management of CD, similar to the NICE guidelines. They can be summarised as CELIAC (Consultation with a skilled dietitian, Education, Lifelong adherence to GF diet, Identification and treatment of nutritional deficiencies, Access to an advocacy group, Continuous long-term follow-up).8

Following a GF diet requires specific education from a specialist dietitian. Self-education and identifying gluten-containing products should also be encouraged.

Physicians should consider the possibility of, and treat, vitamin and mineral deficiencies.

Patients should be encouraged to join Coeliac UK or an equivalent organisation.

There has in the past been some concern that oats can cause mucosal damage, but recent evidence suggests that pure and uncontaminated oats can be safely ingested by most patients with CD, provided they are eaten in limited quantities.

Signs and symptoms or laboratory abnormalities persisting despite six to 12 months on a GF diet occurs in about 7-30% of patients. This can be due to many distinct aetiologies, including inadvertent gluten ingestion (the most common cause), other food intolerances (including lactose and fructose intolerance), small intestinal bacterial overgrowth, microscopic colitis, pancreatic insufficiency, irritable bowel syndrome and refractory CD (RCD).

Refractory CD

RCD is defined as persistent or recurrent symptoms and signs of malabsorption with villous atrophy, despite a strict GF diet for more than 12 months and in the absence of other disorders, including lymphoma.

RCD is rare, affecting 1-2% of patients with CD. There are two types of RCD, type I and type II.

Management of RCD includes the exclusion of unintentional gluten exposure and the treatment of any nutritional deficiencies.22-25

Systemic corticosteroids, enteric-coated budesonide, azathioprine or 6-mercaptopurine, methotrexate, ciclosporin, anti-TNF antibodies or cladribine have been used.

Recent reports have suggested that budesonide or small intestinal release mesalamine may be effective, with fewer side-effects, in type 1 RCD.26-28 Parenteral nutrition may be required in type II RCD, as symptoms are severe and usually do not respond to therapy.

Future potential treatments for patients with RCD include the development of genetically detoxified grains, oral and intranasal 'coeliac vaccines' to induce tolerance, inhibitors of TTG, and detoxification of immunogenic gliadin peptides via oral peptidase supplement therapy.29


Section 4: Prognosis

Studies carried out before the widespread introduction of GF diets reported mortality in patients with CD of up to 20%, due to malnutrition. However, it is now recognised that CD has a more benign course.

Factors that increase mortality in the condition are delayed diagnosis, severe symptoms and the first three years after diagnosis.30-32

Most deaths are attributed to T cell non-Hodgkin's lymphoma.

A reduced risk of breast cancer, lung cancer33and possibly vascular disease34 has been noted.

Follow-up

Long-term follow-up is essential in patients with CD because of the risk of complications and increased mortality. There is also evidence that suggests routine follow-up increases adherence.35,36

The follow-up care of patients with CD varies substantially across the UK, ranging from attendance at specialist clinics to simply being discharged back into the community.

A recent patient survey suggested that patients prefer follow-up with a dietitian, but with access to a gastroenterologist if required.37,38

British Society of Gastroenterology guidelines suggest that patients have FBC, bone profile, ferritin, folate and vitamin B12 levels checked every year. Bone densitometry should be monitored. It is also important to review dietary adherence.

Clinicians should be aware of possible complications, including lymphoma, and investigate or refer if there are clinical suspicions.


Section 5: Case study

A 52-year-old white woman presented with decreased appetite, abdominal pain, bloating and diarrhoea for more than a year.

She had been treated for irritable bowel syndrome by her GP, with no response. She also reported weight loss. Her symptoms varied with diet and she always felt lethargic. She was otherwise well and not on regular medication. She was a non-smoker and teetotal.

Her cousin had coeliac disease, but other family members were well.

The patient weighed 50kg. Apart from mild ankle oedema, physical examination was unremarkable.

Laboratory investigations revealed iron deficiency anaemia (Hb 10.5mg/dL, MCV 72fL, ferritin 10 microgram/L) and mild hypoalbuminaemia. TTG was weakly positive. Upper GI endoscopy and duodenal biopsy were carried out.

Histopathology revealed increased intraepithelial cells and partial villous atrophy.

The patient's genotype testing showed HLA-DQ2.

The clinical features and laboratory investigations were consistent with a diagnosis of coeliac disease, so she was managed with a GF diet and followed up regularly by the specialist dietitian and in the gastroenterology clinic.

She responded well on the GF diet and gained weight. Repeat investigations showed normalisation of TTG and resolution of the anaemia. Endoscopy and duodenal biopsy after one year showed normal appearances. She will have annual follow-up with the specialist team.


Section 6: Evidence base

Clinical trials

  • Phase I study of humanized Mik-beta-1 monoclonal antibody. Mayo Clinic, US, March 2013.

This continuing study is assessing the use of a monoclonal antibody (HU-Mik-beta-1) in the treatment of patients with refractory CD.

  • Phase 2a, randomized, double-blind, placebo-controlled parallel-group study to evaluate the efficacy and safety of AMG 714 for the attenuation of the effects of gluten exposure in adult patients with celiac disease during a gluten challenge. US and Finland, April 2015.

Guidelines

Patient information

Dr Arun Rajendran, ST5 gastroenterology, St Mary's Hospital, London, and Dr Jeremy Nightingale, consultant gastroenterologist, Leonard-Jones intestinal failure unit, St Mark's Hospital, Harrow, Middlesex.

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This is an updated version of an article that was first published in March 2014

References

  1. Gee S. St Bartholomew’s Hospital Reports 1888; 24: 17-20.
  2. Catassi C, Ratsch IM, Gandolfi L et al. Lancet 1999; 354: 647-8.
  3. Cummins AG, Roberts-Thomson IC. J Gastroenterol Hepatol 2009; 24(8): 1347-51.
  4. Rewers M. Gastroenterol 2005; 128(4): S1 (S47-S51).
  5. Cook B, Oxner R, Chapman B et al. NZ Med J 2004; 117: U772.
  6. Kagnoff MF. Gastroenterol Clin North Am 1992; 21: 405-25.
  7. Kagnoff MF. HLA genes in coeliac disease. In: Auricchio SGL, Maiuri L, Troncone R (eds). Coeliac Disease. Naples, JCG Editions, 2000.
  8. James SP. Gastroenterol 2005; 128(4): S1-S9.
  9. Rostom A, Dubé C, Cranney A et al. Celiac disease. Summary, evidence report/technology assessment No 104 (Prepared by the University of Ottawa Evidence-based Practice Center, under Contract No 290-02-0021), AHRQ publication No 04-E)29-1, Agency for Healthcare Research and Quality, Rockville, 2004.
  10. Hopper AD, Cross SS, Hurlstone DP et al. BMJ 2007; 335(7619): 558–562.
  11. Sanders DS, Hurlstone DP, McAlindon ME et al. BMJ 2005; 330: 775-6.
  12. Liu E, Rewers M, Eisenbarth GS. Gastroenterol 2005; 128(4): S1.
  13. Lo W, Sano K, Lebwohl B et al. Dig Dis Sci 2003; 48: 395-8.
  14. Dickey W, Bodkin S. BMJ 1998; 317: 1290.
  15. Sanders DS, Carter MJ, Hurlestone DP et al. Lancet 2001; 358: 1504-8.
  16. Dickey W. Eur J Gastroenterol Hepatol 2002; 14: 425-7.
  17. Sander HW, Magda P, Chin RL et al. Lancet 2003; 362: 1548.
  18. Collin P, Vilska S, Heinonen PK et al. Gut 1996; 39: 382-4.
  19. Kolho KL, Tiitinen A, Tulppala M et al. Br J Obstet Gynaecol 1999; 106: 171-3
  20. Rabsztyn A, Green PH, Berti I et al. Am J Gastroenterol 2001; 96: 1096-100.
  21. Ciclitira PJ, Dewar DH, McLaughlin SD et al. British Society of Gastroenterology. The management of adults with coeliac disease.www.bsg.org.uk/images/stories/clinical/bsg_coeliac_10.pdf (accessed 23 Mar 2017).
  22. Rubio-Tapia A, Kelly DG, Lahr BD et al. Gastroenterol 2009; 136: 99-107.
  23. Malamut G, Afchain P, Verkarre V et al. Gastroenterol 2009; 136: 81-90.
  24. Roshan B, Leffler DA, Jamma S et al. Am J Gastroenterol 2011; 106: 923-8.
  25. Cellier C, Delabesse E, Helmer C et al. French Coeliac Disease Study Group. Lancet 2000; 356: 203-8.
  26. Daum S, Ipczynski R, Heine B et al. Digestion 2006; 73: 60-8.
  27. Brar P, Lee S, Lewis S et al. Am J Gastroenterol 2007; 102: 2265-9.
  28. Jamma S, Leffler DA, Dennis M et al. J Clin Gastroenterol 2011; 45: 30-3.
  29. Shan L, Molberg Ø, Parrot I et al. Science 2002; 297: 2275-9.
  30. Logan RF, Rifkind EA, Turner ID et al. Gastroenterol 1989; 97(2): 265-71.
  31. Cottone M, Termini A, Oliva L et al. Dig Dis Sci 1999; 44(12): 2538-41.
  32. Peters U, Askling J, Gridley G et al. Arch Intern Med 2003; 163(13): 1566-72.
  33. Card TR, West J, Holmes GK. Aliment Pharmacol Ther 2004; 20(7): 769-75.
  34. West J, Logan RF, Card TR et al. Aliment Pharmacol Ther 2004; 20(1): 73-9.
  35. Bardella MT, Molteni N, Prampolini L et al. Arch Dis Child 1994; 70(3): 211-13.
  36. Haines ML, Anderson RP, Gibson PR. Aliment Pharmacol Ther 2008; 28(9): 1042-66.
  37. Bebb JR, Lawson A, Knight T. Aliment Pharmacol Ther 2006; 23(6):827-31.
  38. Nelson M, Mendoza N, McGough N. J Hum Nutr Diet. 2007; 20(5):403-11.
Suggested further CPD activity

These further action points may allow you to earn more credits.

  • Organise an audit of patients in your practice who have CD and review their requests for GF products.
  • Review NICE and British Society of Gastroenterology guidelines for updates on CD management.
  • Arrange a meeting with the CD specialist dietitian and gastroenterologist to discuss a protocol for referring patients who may have CD.

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