Professor Jonathan Brostoff: Irritable Bowel Syndrome

February 02, 2011 0 Comments

Professor Jonathan Brostoff
Honorary Consultant Physician, Guy’s and St Thomas’ Hospital (NHS)
and Hospital of St Johns & St Elizabeth (private practice)
Professor Emeritus of Allergy and
Environmental Health at Kings College, London

Introduction

Irritable bowel syndrome, or IBS, is very common, comprising roughly 30% of those attending gastroenterology outpatient departments. IBS is essentially a descriptive term for “my gut is not happy.” The gut has limited ways to express discomfort, with pain, diarrhea, constipation, wind, and bloating being the main symptoms.

The syndrome can be divided into several clinical groups: post-gastroenteritis, predominant constipation, mainly diarrhea, and alternating diarrhea and constipation. Symptoms not typical in IBS patients include pain at night, fever, diarrhea that disrupts sleep, blood in the stools, and unexplained weight loss. If these symptoms are present, it’s important to see a doctor without delay.

IBS is considered a ‘functional disease’ because there is no obvious associated disease. Colonoscopies typically show no abnormalities, and blood tests are usually normal.

The Causes of IBS

The lack of visible damage in the colon and normal blood tests, often including allergy tests, has led many doctors to consider IBS a psychological issue. However, closer examination of the gut lining in some patients reveals signs of mild inflammation, with mast cells (involved in allergic reactions) being present, suggesting food hypersensitivity as a possible cause.

Other researchers suggest that IBS symptoms may be due to a disturbance in the balance of gut bacteria and yeasts. Symptoms like wind and bloating suggest a form of gut fermentation. Pain, a prominent symptom in some patients, may indicate an abnormality in how nerve impulses are interpreted in the brain.

The Success of Elimination Diets in IBS

Elimination diets have been a neglected yet crucial aspect of IBS treatment. Each year, the gut processes roughly one ton of food and drink, making the gut immune system the most powerful in the body, as it ensures no allergic responses to the foods consumed—a concept known as Oral Tolerance.

There’s a long history of patients being put on diets for various diseases like arthritis, migraine, hyperactivity, Crohn’s disease, eczema, and IBS. Anecdotal reports have shown that eliminating certain common foods can relieve IBS symptoms, but these studies were often ignored by mainstream medical specialists who viewed IBS as psychological.

An early study by Prof. John Hunter at Addenbrooke’s Hospital in Cambridge showed that 70% of patients responded to a standard elimination diet, avoiding common foods like dairy and grains. This has been replicated many times with similar success rates. One notable study by Stefanini and colleagues in Italy found that nearly 70% of IBS patients with predominant diarrhea responded to an elimination diet. A similar percentage was helped by oral Sodium Cromoglycate, a drug that blocks allergic reactions by inhibiting histamine release from mast cells—good evidence that an allergic reaction can occur in the gut lining.

Gut Bacteria and Yeasts in IBS

Involvement of Bacteria: A further study by Prof. John Hunter found IBS more common in patients who took antibiotics after surgery than those who didn’t. The wind and bloating in these patients suggested small intestinal bacterial overgrowth (SIBO). Testing for this condition is simple—patients drink a sugar (lactulose) that is digested by bacteria, producing hydrogen gas measured in the breath. SIBO can be effectively treated with antibiotics.

Involvement of Yeasts: This is a more controversial area, particularly pursued in the USA. Diets eliminating sugar and yeasts seem to help many patients with IBS and other symptoms like water retention, headaches, sinus pain, rhinitis, nausea, flushing, fatigue, aching joints, pre-menstrual syndrome, and possibly vaginal thrush. Patients with ‘too many symptoms’ often go from doctor to doctor seeking relief, resulting in them being labeled as psychological cases. However, a diet eliminating sugar and yeast products, combined with anti-yeast medication, can significantly relieve symptoms.

What Not to Miss

Patients with coeliac disease and IBS have similar symptoms, such as altered bowel habits. If a patient is also anemic, it’s important to exclude gluten sensitivity as a possible cause.

Does an Apple a Day Keep the Doctor Away? The Oral Allergy Syndrome

People with seasonal hay fever are often sensitized to pollens from grass and trees. The main culprit, especially from silver birch pollen, is also found in many fruits and vegetables. Up to 50% of hay fever patients find that eating apples makes their mouth tingle—a sort of ‘hay fever of the mouth.’ Apples and stone fruits contain this allergen, which can lead to symptoms like abdominal pain, wind, diarrhea, or eczema 24 hours later.

The Message

IBS has been a difficult area for both doctors and patients. The lack of abnormalities in biopsies and normal blood tests, despite persistent symptoms, creates a frustrating situation for both parties. However, this is changing due to a greater understanding of the condition. Many clinical studies show that up to three-quarters of patients can feel significantly better with dietary changes and attention to gut microflora. Hopefully, blood tests for many of these aspects will be available in the future.

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