Dr Kevin Barrett discusses the diagnosis of inflammatory bowel disease and how implementing quality standards can improve care for patients

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Read this article to learn more about:

  • causes, symptoms, diagnosis, and treatment of inflammatory bowel disease
  • distinguishing between inflammatory bowel disease and irritable bowel syndrome
  • standards for quality healthcare of people with inflammatory bowel disease.

Key points

GP commissioning messages

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I nflammatory bowel disease (IBD) is a term used to describe a group of conditions that involve inflammation of the gastrointestinal tract. The two main types are ulcerative colitis (a term first used in 1888) and what is now known as Crohn's disease (first described in 1932).1 Table 1 (see below) illustrates the differences between these two conditions. An additional term 'microscopic colitis' covers both collagenous colitis and lymphocytic colitis. Indeterminate colitis (also known as inflammatory bowel disease unclassified) is used when the features lie somewhere between those of ulcerative colitis and Crohn's disease.

Table 1: Differences between ulcerative colitis and Crohn's disease
 Ulcerative colitisCrohn's disease
Location Limited to the colon and rectum Can occur anywhere from the mouth to the anus
Ulceration Continuous Patchy
Bowel lining affected Mucosa only All layers
Affected population More common in adults (3:2) than Crohn's More common in children (2.3:1) than ulcerative colitis
Developed by Dr Kevin Barrett (2016).

Prevalence

The prevalence of IBD in Europe is between 0.5 and 1%, and is rising.2 Estimates of UK prevalence currently vary from 300,000 to 620,000 with a slightly greater proportion of people with ulcerative colitis compared with Crohn's disease.2,3 There is greater incidence of IBD in white people than in African-Caribbean people or those of Asian origin.4 People from a Jewish background have a two to four times increased prevalence.5

Inflammatory bowel disease is a lifelong condition and most commonly first presents in the teens and twenties (25% present in adolescence; median age at diagnosis is 29.5 years),2 although patients can present at any age from infancy onwards and the prevalence in children is increasing.6 Men and women are equally affected.2

Costs associated with IBD

An audit carried out by the Royal College of Physicians in 2014 cited the lifetime medical costs associated with the care of a person with IBD as comparable to those of major chronic diseases such as diabetes mellitus or cancer. An estimate of the annual average cost per patient of up to £3000 in 2006 would result in a likely average annual cost to the NHS based on prevailing estimates of prevalence of £900 million.3 One-half of all direct annual healthcare costs associated with IBD are related to the inpatient management of a minority of patients who need intensive medical or surgical intervention.2 It is expected that with increased use of biologic agents the number of patients requiring surgical intervention will fall.7

Causes

The cause of IBD is likely to be multifactorial; a Danish study showed that genetic predisposition increases the risk by seven-fold in first-degree relatives and may also determine the pattern and severity of the conditions.8 An abnormal reaction of the immune system to intestinal bacteria triggered by environmental factors is a likely cause; an increase in diagnosis in second- and third-generation immigrants to Western countries supports this prognosis.9 There is no clear evidence that diet is a significant factor in causing IBD.10,11

Symptoms

Urgent and frequent diarrhoea are the most common symptoms, together with rectal bleeding, pain, bloating, profound fatigue, malaise, and anaemia.2,4 Manifestations outside the gastrointestinal tract are common, and can include associated arthritis (in approximately 15–20% of patients with Crohn's disease and approximately 10% of patients with ulcerative colitis).12 The skin may be affected (erythema nodosum or pyoderma gangrenosum; primary sclerosing cholangitis—more common in patients with ulcerative colitis) and there may be ocular complications (uveitis, iritis, or episcleritis). Malnutrition, anaemia, and weight loss are common, particularly in Crohn's disease. Strictures, bowel obstruction, perforation, or fistulas can occur in Crohn’s disease, and can present as an acute abdomen.

The pattern of symptoms is often different in children; 44% of children with Crohn's disease did not report symptoms of diarrhoea.13 Paediatric IBD is often more extensive at diagnosis than in adults.5

Diagnosis

Acute severe colitis carries a mortality risk of 1–2% and there is a 29% chance that an emergency colectomy will be required, so early diagnosis or detection and intervention in a flareup is key.2 In addition to this higher incidence of surgical intervention, delayed diagnosis of IBD is associated with reduced response to medical therapy.14

Primary care pathways for investigating adults with persistent lower gastrointestinal symptoms should include testing of inflammatory markers and coeliac antibodies, and excluding an infective cause when this is suspected (see Figure 1, below). If these tests are normal, then faecal calprotectin testing with a cut off value of 50 µg/g (depending upon local laboratory recommendation) should be undertaken. If all these tests are normal, then a diagnosis of IBS can be made.15

example pathway for the investigation of an adult with lower gastrointestinal symptoms in primary care

Figure 1: Example pathway for the investigation of an adult with lower gastrointestinal symptoms in primary care

Developed by Dr Kevin Barrett (2016).

GI=gastrointestinal; NG=NICE Guideline; QS=Quality Standard; IBD=inflammatory bowel disease; FBC=full blood count; CRP=C-reactive protein; TFT=thyroid function test; IBS=irritable bowel syndrome

Differentiation from irritable bowel syndrome

Inflammatory bowel disease and irritable bowel syndrome (IBS) are different conditions, although there is an overlap in many of the symptoms and in the main age group affected. However, IBS is a functional bowel disorder with no structural or currently measurable pathology and a prevalence of between 10% and 20% of the population.16 It is therefore necessary to exclude the presence of IBD before diagnosing IBS.17 It is also important to consider a new diagnosis of IBD in people with longstanding IBS whose symptoms change, as delays in diagnosis can often occur in this group of patients. Faecal calprotectin testing can be used to aid differentiation between the two conditions.4

Faecal calprotectin testing

NICE Diagnostics Guidance 11 (DG11) recommends faecal calprotectin testing as an option to support clinicians in differentiating between IBD and IBS in adults with recent-onset lower gastrointestinal symptoms if cancer is not suspected,4 and this approach is supported by the British Society of Gastroenterology.18 Calprotectin is excreted in excess into the intestinal lumen during the inflammatory process and is a more specific test for bowel inflammation than C-reactive protein and erythrocyte sedimentation rate inflammatory markers.

Use of faecal calprotectin testing can result in a reduction of between 56% and 71% of patients presenting with lower gastrointestinal symptoms being referred to gastroenterology,19,20 with an associated reduction in costs for the NHS of approximately £740 (for an outpatient appointment, colonoscopy, and follow-up appointment) together with benefits for patients—up to 40% still experience effects for 30 days after the colonoscopy.4 The NHS Business Services Authority has estimated that £55 million to £266 million could be saved if faecal calprotectin testing was available throughout England.20

Whether near-patient or laboratory testing, faecal calprotectin is becoming an essential part of the diagnosis of IBD and its use should be encouraged. NICE published its Diagnostics adoption support in July 2015 to help trusts and commissioning groups to offer this test to their patients.15

Faecal calprotectin testing is also recommended by the British Society for Gastroenterology for follow up of patients with IBD for detection of relapse or treatment failure in secondary care,18 but this has yet to be widely adopted for use in primary care.

Standards for quality healthcare of people with IBD

In 2013, the IBD Standards Group produced Standards for the healthcare of people who have inflammatory bowel disease.2 This was followed in 2015 by the publication of NICE Quality Standard (QS) 81 on Inflammatory bowel disease.21 Both pieces of guidance aim to ensure that patients with IBD:

  • receive consistently high-quality care from the time they first present to a healthcare professional, through the diagnostic process, treatment, changes in their condition, development of associated conditions or complications, and during any hospital stays
  • are prescribed any drugs they need and are monitored appropriately
  • receive appropriate support to enable them to manage their lives effectively and ongoing surveillance.

NICE QS81 is mapped to four of the key domains included in the NHS Outcomes Framework 2015–2016,22 and to three of the key domains from the Public Health Outcomes Framework for England 2013–2016.23

NICE QS81 is intended to improve the following outcomes:21

  • attendance at school
  • sickness absence from work
  • unplanned hospital admissions for IBD
  • length of hospital stay after surgery or for IBD
  • readmissions after surgery for IBD
  • people with long-term conditions feeling supported to manage their condition
  • patient experience of services.

Specialist assessment

In QS81 NICE recommends that: People with suspected inflammatory bowel disease have a specialist assessment within 4 weeks of referral (statement 1).21

'Suspected IBD' refers to those individuals with lower gastrointestinal symptoms and raised inflammatory markers or raised faecal calprotectin. Some people with severe symptoms will need a more urgent assessment;21 for example the British Society for Gastroenterology recommends an urgent referral if a faecal calprotectin level is >250 µg/g.18

Multidisciplinary team support

Inflammatory bowel disease follows an often unpredictable relapsing-remitting course and as a result education, employment, personal relationships, and social and family life may all be affected. The frequent and urgent need for the toilet, together with pain and fatigue, can severely affect self-esteem and social functioning, particularly among the young and newly diagnosed.

NICE QS81 recommends that: Services provide age-appropriate support from a multidisciplinary team for people with inflammatory bowel disease, and their family members or carers (statement 2).21

A multidisciplinary team (MDT) should include all of the following, and all members should have a special interest in IBD:2

  • specialist IBD nurses, accessible by telephone or email the same working day by both patients and GPs. The IBD Standards Group standard A1 recommends 1.5 whole-time equivalent specialist nurses per 250,000 population2
  • stoma nurse
  • consultant gastroenterologist
  • consultant colorectal surgeon
  • dietitian
  • pharmacist
  • radiologist
  • histopathologist.

There should also be support available from:2

  • psychologists or counsellors
  • rheumatologists
  • ophthalmologists
  • dermatologists
  • obstetricians
  • a nutrition support team
  • paediatricians, with planned transition to adult care
  • a GP to act as liaison with local GPs.

The MDT is a key part of achieving the top 10 essentials of a good IBD service drawn up by Crohn’s and Colitis UK (see Box 1, below).24

Box 1: Top 10 essentials of a good IBD service24

  1. My IBD team: I am supported by a team of IBD specialists who help me manage my condition
  2. Someone to contact: I know who to contact quickly if I need advice or if my condition changes
  3. Personalised care: my care is appropriate for me and takes account of my age, preferences, personal values, and goals
  4. Joined-up care: my care is coordinated between the different health professionals involved
  5. Informed choices: I am offered different options for my treatment and care so that I can understand and choose what is right for me
  6. Participation in decision-making: I am fully involved in all decisions about my care and, if I wish to, am able to include a family member, carer, or friend in my decision-making
  7. A clear plan: I work with my IBD team to agree a plan for my care and have regular reviews with a member of the team to monitor my health and well-being
  8. Living with IBD: I am given information and offered ongoing support to understand and manage my life with IBD
  9. Going into hospital: my IBD team are informed if I am admitted to hospital
  10. Improving my service: I am asked for feedback on my experience of care and am able to play a role in improving my service

Crohn's & Colitis UK. My Crohn's and Colitis Care. Crohns & Colitis UK. 2015. Available at: www.crohnsandcolitis.org.uk/about-inflammatory-bowel-disease/publications/my-crohns-and-colitis-care


Primary care should also be considered part of the multidisciplinary team. The patient's GP has a key role in the initial diagnosis, ongoing support, prescribing and monitoring of medication (with shared-care protocols where appropriate), as well as supporting the patient to return to education, work, or normal family life as soon as possible.

The IBD Standards Group (standard D3) recommends that all patients should be provided with contact information for the relevant patient organisations so they can access additional help and support;2 for example, Crohn's and Colitis UK produces a wide range of information sheets and booklets on all aspects of living with IBD and offers a telephone and email information service, online forum, and local support networks.

 

Surgery

About 30% of patients will fail to respond to aminosalicylates (5ASAs) or immunosuppressant drugs, or are intolerant of them and these patients may then be considered for biologic therapies or surgery. At least 50% of patients with Crohn’s disease may require surgery within 10 years of diagnosis, and 70–80% may require surgery during their lifetime.25 In ulcerative colitis, total lifetime surgery rates are approximately 20–30%.2,4

Both NICE QS81 (statement 3) and IBD Standards Group (standard A7) recommend that surgery for IBD should be undertaken by a colorectal surgeon who is a core member of the IBD MDT.2,21

Medication

There is currently no cure for IBD. Aminosalicylates, corticosteroids, biologic agents, and immunomodulating drugs are the mainstay of medical management for inducing and maintaining remission depending on the type and severity of disease, side-effects, contraindications, and patient age and choice (see Table 2, below).26–28 For Crohn's disease, enteral nutrition is often the therapy of choice in children, and can be used to induce remission in adults. Around 50% of patients experience at least one relapse each year.2

Table 2: Drugs used to treat inflammatory bowel disease28
Drug classExamplesMonitoring required in primary care*Significant side-effects
Corticosteroids Prednisolone
Dexamethasone
Budesonide
Intravenous hydrocortisone
Assess for:
  • osteoporosis
  • Cushingoid features
  • hypoglycaemia
  • cataracts or glaucoma
Systemic infection
Diabetes
Heart failure
Psychiatric effects
Sleep disturbance
Osteoporosis
GI upset
Growth suppression in children
Acne
Weight gain
Aminosalicylates (5ASAs) Mesalazine
Sulfasalazine
Mesalazine: U&E annually
Sulfasalazine: FBC & LFT every 3 months
Headache
Can occasionally worsen ulcerative colitis
Immunosuppressants Azathioprine
Mercaptopurine
Methotrexate
Once stable:
  • FBC and LFT every 3 months
  • U&E every 6 months (every 3 months for methotrexate)
Increased susceptibility to sunburn
Increased risk of cervical abnormalities
Increased susceptibility to infections
Bone marrow suppression
Liver damage
Biologic agents Infliximab
Adalimumab
Golimumab
Vedolizumab
Not often done in primary care, but once stable: FBC, CRP, U&E, LFT every 3–6 months
Lipid profile and hepatitis B status should be checked periodically
Injection site skin reactions
Increased susceptibility to infections including tuberculosis
Increased risk of some cancers, particularly lymphoma
* once the patient is on a stable, long-term dose (may differ according to local guidance)
GI=gastrointestinal; U&E=urea and electrolytes; FBC=full blood count; LFT=liver function test; CRP=C-reactive protein
Developed by Dr Kevin Barrett (2016).

NICE QS81 statement 4 states that: People receiving drug treatment for IBD are monitored for adverse effects.21 Shared-care agreements between primary and secondary care are needed to ensure safe prescribing and monitoring of some medications.

Contraception and pregnancy

Inflammatory bowel disease often occurs in patients of child-bearing age. Many medications are contraindicated in pregnancy and breastfeeding so contraception should be discussed when prescribing, bearing in mind the potential for reduced absorption of oral contraceptives from the gastrointestinal tract.29 It is important to counsel couples who are considering pregnancy about the potential added complications of malabsorption of nutrients, and issues arising from pregnancy for those with a stoma. These subjects are often best discussed in conjunction with the MDT. Additional patient information is available from Crohn's and Colitis UK.

Osteoporosis

NICE CG146 recommends measuring bone mineral density to assess fracture risk in people aged under 40 years who have a major risk factor, including current or recent use of high-dose oral or high-dose systemic glucocorticoids (more than 7.5 mg prednisolone or equivalent per day for 3 months or longer).30

Bowel cancer

There is an established link between IBD and an increased risk of developing colorectal cancer (see Table 3, below).31 The risk of developing colorectal cancer for people with extensive ulcerative colitis is estimated as 2% after 10 years, 8% after 20 years and 18% after 30 years of disease. The risk of developing colorectal cancer for people with Crohn's disease is considered to be similar to that for people with ulcerative colitis with the same extent of colonic involvement.31

Table 3: Risk of developing colorectal cancer in people with inflammatory bowel disease31
Risk levelPredisposing conditionFrequency of assessment
Low
  • Extensive but quiescent ulcerative colitis
  • Extensive but quiescent Crohn's colitis
  • Left-sided ulcerative colitis (but not proctitis alone) or Crohn's colitis of a similar extent
Colonoscopy every 5 years
Intermediate
  • Extensive ulcerative or Crohn's colitis with mild active inflammation that has been confirmed endoscopically or histologically
  • Post-inflammatory polyps
  • Family history of colorectal cancer in a first-degree relative aged 50 years or over
Colonoscopy every 3 years
High
  • Extensive ulcerative colitis or Crohn's colitis with moderate or severe active inflammation that has been confirmed endoscopically or histologically
  • Primary sclerosing cholangitis (including after liver transplant)
  • Colonic stricture in the past 5 years
  • Any grade of dysplasia in the past 5 years
  • Family history of colorectal cancer in a first-degree relative aged under 50 years
Annual colonoscopy
Developed by Dr Kevin Barrett (2016).

Summary

Diagnosing IBD can be difficult as the symptoms often overlap with several other conditions, and the pattern of symptoms is not always consistent, particularly in children. The use of faecal calprotectin testing can be very useful as a diagnostic tool for both clinicians and commissioners due to the potential reduction in unnecessary referrals and colonoscopies, and widespread availability of this test is recommended. A multidisciplinary approach is needed to support patients and their families; IBD nurses are a key component of this team and they can facilitate good coordination between primary and secondary care throughout the patient's lifetime.

 

GP commissioning messages

written by Dr David Jenner, GP, Cullompton, Devon

  • Commissioners should review the local provision of services for patients with IBD and ensure all key components recommended by NICE are available
  • Commissioners and providers should work together to establish clear diagnostic and referral pathways for suspected IBD such that all people with suspected IBD are seen within 4 weeks of referral
  • Faecal calprotectin testing should be commissioned as part of this pathway and available to primary care—this is likely to be cost effective in reducing colonoscopy rates
  • The biologic medications that will increasingly be used in the management of IBD are expensive and although these are prescribed by secondary care, the costs fall to CCG budgets as 'pass through drugs'
  • Commissioners should agree formularies with specialist providers for the required medication and agree shared-care guidelines for some of the immunomodulating drugs that require monitoring in primary care with blood tests
  • CCGs should consider commissioning specialist IBD nurses who can take direct referrals from GPs and also patients with established IBD to allow a prompt response to relapses.

IBD=inflammatory bowel disease

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Key points

  • The prevalence of IBD is rising, particularly in children, although it can occur at any age
  • The cause is multifactorial—genetics play a part
  • Diarrhoea is the most common symptom, but not necessarily in children
  • IBD can occur in patients with a previous diagnosis of IBS
  • Faecal calprotectin testing can be used to help differentiate between IBD and IBS
  • Problems outside the gastrointestinal tract can occur, such as primary sclerosing cholangitis, skin problems, and iritis
  • There is no cure—treatment is based on achieving and maintaining remission, with relapses likely
  • Medication requires ongoing monitoring
  • Multidisciplinary teams, especially IBD nurses, are key to supporting patients
  • There is an increased risk of bowel cancer with IBD, particularly in those with more extensive or active disease.

IBD=inflammatory bowel disease; IBS=irritable bowel syndrome

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References

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  2. IBD Standards Group. Standards for the healthcare of people who have inflammatory bowel disease (IBD). IBD Standards, updated 2013. Available at: www.ibdstandards.org.uk/uploaded_files/IBDstandards.pdf
  3. RCP. National audit of inflammatory bowel disease (IBD) service provision: UK IBD audit. London: RCP, 2014. Available at: www.rcplondon.ac.uk/projects/outputs/ibd-organisational-audit-adult-report-round-four-2014
  4. NICE. Faecal calprotectin diagnostic tests for inflammatory diseases of the bowel. Diagnostics Guidance 11. NICE, 2013. Available at: www.nice.org.uk/dg11
  5. Yang H, McElree C, Roth M-P et al. Familial empirical risks for inflammatory bowel disease: differences between Jews and non-Jews. Gut 1993; 34 (4): 517–524.
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  14. Mozdiak E, O’Malley J, Arasaradnam R. Inflammatory bowel disease. BMJ 2015; 351. doi: dx.doi.org/10.1136/bmj.h4416
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  16. NICE. Irritable bowel syndrome in adults: diagnosis and management. Clinical Guideline 61. NICE, 2008. Available at: www.nice.org.uk/cg61
  17. NICE. Irritable bowel syndrome in adults. Quality Standard 114. NICE, 2016. Available at: www.nice.org.uk/qs114
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  20. NHS Business Services Authority. Pacific case study: faecal calprotectin testing. NHSBSA, 2016. Available at: www.nhsbsa.nhs.uk/Documents/NHSBSA_publication_centre/FINAL_Faecal_calprotectin_case_study_(V2)_March_2016.pdf
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