Inflammatory Bowel Disease Overview

Patient - GIE

• The lecture covers Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD)
• IBS is a chronic condition affecting the gastrointestinal tract
• IBS symptoms vary between people, and some are more severely affected than others
• IBS is estimated to affect around 15% of the adult population, with women being more likely to be affected
• The cause of IBS is not fully understood but thought to relate to increased gut sensitivity and digestion problems. Stress can trigger symptoms and certain foods might also trigger them.
• IBS symptoms can include abdominal pain, cramping, changes in bowel habits (constipation, diarrhoea, or both), bloating, flatulence, tenesmus (urgency to defecate), and passing mucus from the rectum.

Lower GI Anatomy

• A diagram of the lower gastrointestinal tract was presented, labelling various parts
• The diagram depicts the stomach, small intestine (with duodenum, jejunum, and ileum labelled), and large intestine segments (colon).

Irritable Bowel Syndrome (IBS) Overview

• IBS is a chronic condition affecting the gastrointestinal tract.
• IBS symptoms are variable from person to person.
• It's believed to affect about 15% of adults, with women being more likely to be affected.
• The exact cause of IBS is unknown, but increased gut sensitivity and issues digesting food are suspected factors.

IBS Symptoms

• Abdominal pain and cramping
• Changes in bowel habits (constipation, diarrhea, or both)
• Bloating
• Flatulence
• Tenesmus (urgency to defecate)
• Passing mucus from the rectum
• Symptoms like lethargy, nausea, backache, and bladder symptoms might also be present.

Types of IBS

• IBS-C (Constipation): Hard/lumpy stools for at least 25% of bowel movements, with loose/watery stools for less than 25%.
• IBS-D (Diarrhoea): Loose/watery stools for at least 25% of bowel movements, with hard/lumpy stools for less than 25%.
• IBS-M (Mixed): Hard/lumpy stools for less than 25% of bowel movements and loose/watery stools for less than 25%.
• Unspecified IBS: Insufficient stool consistency abnormality to meet IBS-C, IBS-D, or IBS-M criteria.

IBS Diagnosis

• Consider IBS if symptoms have persisted for at least 6 months
• Symptoms include abdominal pain/discomfort, bloating, and altered bowel habits.
• Rule out other conditions like cancer, inflammatory bowel disease, and coeliac disease
• IBS is diagnosed if abdominal pain or discomfort is eased or linked with bowel changes together with at least two of the following: altered bowel frequency or stool consistency; abdominal bloating, distention, or hardness; worsened by eating; mucus passage.

Management of IBS (Dietary and Lifestyle)

• Maintain a balanced and well-structured diet.
• Prioritise unhurried meals.
• Ensure adequate non-caffeinated water intake (at least 8 cups) and restrict caffeinated drinks (limit to 3 cups daily).
• Minimise alcohol and fizzy drinks consumption.
• Reduce high-fiber food (especially insoluble fiber) intake.
• Limit high-fiber foods, particularly insoluble fiber.
• Limit the intake of fructose, lactose, fructans, and polyols.
• Consider an elimination diet if symptoms persist.
• Regularly maintain a detailed diary to identify triggers and keep track of the symptoms and foods consumed and their relation.
• Prioritise activities that induce relaxation.

Management of IBS (Pharmacological Therapy)

• Antispasmodic agents (e.g., hyoscine butylbromide, mebeverine, peppermint oil) are used to manage pain or cramps.
• Loperamide is the first-line antimotility drug for diarrhea.
• Macrogol is preferred for chronic constipation.
• Additional medications (e.g., laxatives like ispaghula husk, linaclotide, prucalopride, tricyclic antidepressants, selective serotonin reuptake inhibitors) can be considered.

Inflammatory Bowel Disease (IBD)

• IBD describes two conditions: Crohn's Disease (CD) and Ulcerative Colitis (UC)
• Both are chronic and relapsing conditions that cause inflammation in the gastrointestinal tract.

IBD: Epidemiology

• IBD is more common in Northern Europe and North America, with Caucasians being more commonly affected.
• Incidence is rising in Asian countries.
• Women with CD have a slightly higher risk (20-30%) compared to men.
• UC and CD peak in patients aged 10-40, affecting 10-20/100,000 people per year with a similar prevalence (approximately 240/100,000 for UC and 145/100,000 for CD.

IBD: Aetiology

• A combination of genetic and environmental factors contributes to IBD.
• Stress, antibiotics, and dietary factors are also implicated. Host genetic factors, environmental factors and microflora are important causal elements.

IBD Diagnosis

• Faecal calprotectin, full blood count (FBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), iron studies, B12, and folate levels are checked.
• Flexible sigmoidoscopy, colonoscopy, and upper GI endoscopy (for CD) are performed.
• Biopsies are sometimes necessary.

Ulcerative Colitis (UC)

• UC inflammation is always continuous and limited to the colon and rectum (non-transmural).
• Different types of UC include proctitis, proctosigmoiditis, left-sided colitis, and pancolitis, depending on the affected areas.

UC: Aetiology

• A combination of genetic and environmental factors are involved.
• Stress, infections and dietary habits are among environmental risk factors.

UC: Clinical Features

• Bloody diarrhea
• Rectal bleeding
• Colicky abdominal pain
• Abdominal urgency for defecation
• Tenesmus (rectal urgency)

UC: Assessment of Severity

• The Truelove and Witts system is used to assess the severity of UC, based on various clinical findings (bow movements, blood in stools, fever, pulse rate, anaemia, ESR) which are scored into mild, moderate, and severe categories.

Crohn's Disease (CD)

• CD can affect any part of the gastrointestinal tract.
• Inflammation is typically discontinuous and transmural.
• Common classification involves ileocolitis, with other forms based on location or pattern.

CD: Aetiology

• Genetic factors and environmental factors such as infections, psychosocial stress and smoking are involved (the interaction of both is thought to cause inflammatory responses).
• Refined carbs are also often linked to increased risk in patients with the disease.

CD: Clinical Features

• Abdominal pain
• Weight loss
• Diarrhea
• Intestinal obstruction (due to strictures, fistulae, or abscesses)

Fistulas

• Fistulas are abnormal tunnels that emerge between two body cavities or from a cavity to the skin.
• They are often linked to inflammation and ulcer/abscess formation.
• Enterocolic fistula are specifically linked with the small or large intestine.

CD: Assessment of Severity

• The Harvey Bradshaw index gauges CD severity (based on clinical indicators e.g. well being, abdominal pain, liquid stool regularity, abdominal mass).

IBD Treatment and Management

• Treatment varies depending on the type and severity
• Dietary modifications, relaxation, and lifestyle counselling are often advisable in conjunction with medical intervention and monitoring/control of side-effects.
• Medications frequently administered in IBD treatments include corticosteroids, aminosalicylates, immunosuppressants, and biologics.
• When appropriate surgically removing/resectioning damaged parts of the GI tract might be implemented.

IBD: Treatments - Specifics

• Corticosteroids: Effective for acute attacks and inducing remission, used in liquid or foam enema forms in localised disease or oral/parenteral options in severe/extensive disease.
• Aminosalicylates: Induce and maintain remission in UC, administered orally or topically/rectally.
• Immunosuppressants, such as azathioprine and mercaptopurine, often used as maintenance therapies to maintain treatment response.
• Methotrexate may serve in those resistant to azathioprine or mercaptopurine treatments.
• Biologics, such as infliximab and adalimumab, are used in severe/non-responsive cases.

IBD: Maintenance Treatment for specific conditions

• UC proctitis and proctosigmoiditis: Topical aminosalicylates, oral aminosalicylates, or both, are options for treatment.
• UC left-sided and extensive disease (topical/oral aminosalicylates can be administered in conjunction with oral aminosalicylate high doses for maintenance).
• CD: Azathioprine or mercaptopurine, methotrexate (if used initially to induce remission but did not tolerate it or contraindications exist for aza/mp or other options) are potential alternatives or corticosteroids should be avoided as maintenance treatment options.
• Corticosteroids (e.g hydrocortisone, prednisolone) may be initially considered for acute exacerbations and are not generally appropriate for remission maintenance. Instead, treatment should focus on immunomodulatory or biologic agents when appropriate.

Rectal Administration of Medication in IBD

• Medication can be delivered rectally via suppositories or foam and enema routes to target specific parts of the large intestine.

Aminosalicylates

• Aminosalicylates are anti-inflammatory drugs used in IBD management, particularly in UC.
• Sulfasalazine is a prodrug, converting to 5-aminosalicylic acid in the intestines.
• Various formulations of aminosalicylates (mesalazine, olsalazine, balsalazide) exist with different targets and side effects (e.g. rectal-administered mesalazine is available via suppositories).

Aminosalicylates: Side Effects

• Common side effects include diarrhea, nausea, vomiting, and abdominal pain.
• Rare, but more serious side effects include pancreatitis, hepatitis, skin reactions, and blood dyscrasias.

UC: Acute Severe Disease

• Hospital treatment might be needed for severe cases, possibly involving IV corticosteroids (e.g hydrocortisone) and/or IV ciclosporin, especially in those whose treatment responses are poor or insufficient.
• Immunosuppressive therapy could be beneficial, particularly in unresponsive cases of UC acute severe disease.
• Infliximab might prove useful in persistent or non-responsive cases, but it is crucial to monitor for major complications such as renal impairment and electrolyte disturbances.

CD: Inducing Remission

• First-line treatment for new onset or single exacerbation within a 12-month timeframe typically involves conventional glucocorticoid treatment such as prednisolone, methylprednisolone, or IV-administered glucocorticoid drugs.
• Additional therapy using azathioprine, mercaptopurine, or methotrexate is considered if warranted based on exacerbations or other factors.
• Infliximab or adalimumab are possible choices if the disease is not controlled by conventional therapies.

Immunosuppressants

• Azathioprine is metabolised to mercaptopurine.
• Approximately 1/300 patients are deficient in TMPT (thiopurine methyltransferase) which is essential for mercaptopurine metabolism. This can lead to drug toxicity or blood dyscrasias.
• TMPT deficiency results in altered mercaptopurine metabolism potentially causing complications.
• Monitor TMPT activity prior to initiation and blood counts (complete blood count – FBC – at least initially weekly) during the initial 4 weeks and periodically during maintenance treatment.
• Regular monitoring for toxicities is critical, especially blood dyscrasias. Methotrexate is an alternative option for immunomodulation if azathioprine/mercaptopurine cannot be used or tolerated, potentially useful in refractory cases.

Biologics

• Infliximab is a chimaeric monoclonal antibody targeting TNFa.
• It neutralises TNFa and might induce cell apoptosis. A single 5 mg/kg dose is often administered as an infusion.
• Biologic therapies can potentially be suitable for various specific uses, but detailed patient monitoring and close investigation/treatment of potential side effects should be part of treatment protocols.
• Adalimumab, vedolizumab, ustekinumab, and golimumab (for UC only) are other biologics used in IBD cases.

Surgery

• Ostomy surgery involves creating a surgical opening in the abdominal wall for waste removal, which could either be temporary or permanent.
• Colostomy involves a section of the colon, whilst ileostomy uses an intestinal section.

Stoma Care and Ostomy Bags

• Various stoma care resources are available online, mainly focused on patient education and care guidance, including videos.

IBD: Extraintestinal Manifestations

• IBD can affect areas outside the GI tract, though more commonly in CD than UC.
• Symptoms can include anaemia, arthropathy, skin effects, eye effects, hepatobiliary problems, mucocutaneous lesions, fever, and tachycardia.

IBD: Associated Care Issues

• Associated care issues include managing smoking, vaccinating, pain management, monitoring for colonic carcinoma, providing nutritional advice, and managing extraintestinal manifestations.

IBD: Patient Experience

• Information about IBD can be found via dedicated national organisations (such as Crohn's and Colitis UK).
• Organisations often provide patient-focused resources, information about awareness campaigns and patient experiences, usually in the form of webpages and social media channels.

IBD: Check your Learning

• A table comparing the common features of UC (Ulcerative Colitis) and CD (Crohn's Disease) is provided in this section for a quick reference summary.

Further Reading

• Relevant pharmacology textbooks and clinical therapeutics textbooks can be used for deeper insights.
• Online resources for further reading and guidance about IBD, such as NICE guidelines (CG61 for IBS, NG129 and NG130 for CD and UC respectively), are available and recommended.
• The British National Formulary, Clinical Key, and BMJ Best Practice are also valuable resources.
• Websites for the British Society of Gastroenterology (BSG) provide valuable detail.

Test your knowledge on inflammatory bowel diseases such as Crohn's disease and ulcerative colitis. This quiz covers diagnosis methods, symptoms, dietary changes, and treatment options. It's perfect for anyone studying or interested in gastrointestinal health.