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IBS: diagnosis and management in 2011

Nick Read
Gastroenterologist and Psychotherapist
Chair
The Gut Trust/IBS Network 

Irritable bowel syndrome is the term used by doctors, nurses and other health workers to describe a combination of chronic abdominal discomfort and bowel disturbance that cannot be explained by any other definitive disease of the gut

Although strenuous efforts have been made by committees of "experts" to arrive at a positive diagnosis of IBS (see Box 1), it remains a diagnosis of exclusion.1 The features of IBS, the pain, the bloating, the bowel upset and feelings of frustrated defecation can be produced by any disease process that affects the lower gut; they represent the way that particular anatomical region reacts to irritation, whether this is produced by infection, inflammation, allergy, food intolerance, or affected by the memory or meaning of life events.

[[Box 1 IBS1]]
 
All positive criteria for IBS include the caveat, "In the absence of a structural or biochemical reason for the symptoms". Rectal bleeding, fever and weight loss are red flag symptoms that are not normally found in IBS and alert GPs and practice nurses to the possibility of inflammatory bowel disease, cancer or
coeliac disease.1 

Inflammatory bowel disease (IBD), coeliac disease and bowel cancer are three most common and serious chronic bowel conditions that can be confused with IBS, but unlike it, can be treated effectively with diet, drugs and surgery. Each of these conditions can present with symptoms identical to those of IBS.

A three-year study found that patients diagnosed with IBS were 16.3 times more likely to be diagnosed with Crohn's disease or colitis during the study period.2 Coeliac disease is four times as common in people diagnosed with IBS and bowel cancer may frequently commence with malaise and non-specific abdominal symptoms.3 The saving grace is that "a serious illness will usually show its hand". The chronic symptoms of IBD, coeliac disease and bowel cancer will inevitably come to include a red flag symptom, such as weight loss, anaemia or rectal bleeding that should alert the assiduous clinician - but how much better if they were to pick up these conditions sooner.           

Therefore, in our modern evidence-based NHS, it is the responsibility of the GP and the practice nurse to ensure that their patients with chronic symptoms of bowel irritation do not have a condition that demands specific treatment. 

This does not require the familiar battery of expensive, hospital-based endoscopic and radiological procedures. It just needs a few well-chosen and sensitive screening tests that can be sent off from the practice without referral to a specialist. IBD always used to be screened by checking the ESR (erythrocyte sedimentation rate) or C-reactive protein, but nowadays there is a more sensitive immunological test: faecal calprotectin, a protein derived from white blood cells shed into the gut.4 Coeliac disease can be all but ruled out with tests for anti-gliadin, endomysial and antireticulin antibodies. Bowel cancer can be screened by chemical or immunological tests for faecal occult blood or faecal calprotectin. But medicine is not an exact science. A positive test does not necessarily establish a diagnosis - it may just indicate a proclivity or it may even be caused by some other condition. Interpretation of test results can only be made in the context of the clinical presentation. Among the most common causes of rectal bleeding are anal fissures and piles.

Similarly, a negative screen does not establish the diagnosis of IBS; it just gives the clinician more confidence by making it more likely. A patient with chronic abdominal symptoms who continues to lose weight should alert the clinician to other possibilities. I recently received a letter from the sister of a patient who had been diagnosed with IBS but had lost three stone in weight in the previous year. Her scans were reviewed and pancreatic cancer was diagnosed. This is not an argument for ever-more elaborate or expensive screening procedures, just a caution for the application of common sense.  

It is much more important to know the patient with the illness than to know the illness in the patient. The great American clinician, William Osler, said as much 100 years ago, although with the increasing dependence on scientific evidence, the art and poetry of medicine has been largely forgotten. In my book, Sick and Tired, Healing the Illnesses Doctors Cannot Cure, I make the point that, for otherwise unexplained illnesses like IBS, chronic fatigue syndrome or fibromyalgia syndrome, it is important to know your patient so you understand the way their body reacts to stress and can identify when the symptoms do not fit with their usual pattern and need to be investigated.5 Our modern system of medicine tends to put the body scanner in the cart before the horse. 

Treatment
So you have a patient with IBS; you have screened out the most common organic conditions, and there is little point in referring the patient to a gastroenterologist to have the diagnosis confirmed. Medically unexplained symptoms are often exacerbated by referral to "specialists" who have a different agenda and will inevitably let them down. No, the buck stops with you and your patient. Was that a sigh? People with IBS can often cause the hearts of GPs and practice nurses to sink, which is not the best reaction for an effective therapeutic relationship. Why? Well the clue lies in what so many of the members of the Gut Trust write and tell us: "My doctor doesn't listen to me."   

IBS is often a message expressed in a medical narrative that will attract the doctor's attention. The themes of what has been happening to the patient are often there in the nature of the symptoms, but to get at them, the message needs to be decoded.  

It's not computer science! The enigma is with the patient. Take your time. Listen, try to understand what has happened. When somebody says their abdominal pain makes them feel desperate, ask yourself, "What is it that's making them so depressed or desperate?" Surely not just the bowel symptoms! Our bowels can betray our guilty secrets, letting the bad stuff out or holding it in, they can embarrass us with shame, and let us down. As Freidrich Nietzsch declared, "All prejudices take their origin in the intestines" - deposited there presumably by dysfunction of the autonomic nervous system.     

But managing IBS should not be seen as divination for medical mystic Megs; it's merely a matter of listening and asking a few penetrating questions. What was going on when the symptoms first started? What tends to relieve them? What brings them back again? What do they represent for you? Do they remind you of anything? 

Questions about diet may also help, but true food allergies are rare in IBS. Most patients tend to have an intolerance to food that is related to an enhanced bowel sensitivity and/or to what memory that particular food holds for them. One of my patients developed a severe intolerance to fish (and subsequently to other foods) after her then boyfriend took her out to a meal at which he admitted he was having a relationship with somebody else, who became pregnant. The symptoms of her traumatic food intolerance were recruited to express her continued disappointment and shame.

Such situations are not uncommon. In a project we carried out some years ago to investigate IBS that comes on for the first time after an attack of gastroenteritis, we found that persistent bowel symptoms were more likely to develop if the patient was female or had suffered from anxiety, depression or some particularly traumatic life event at the time of their episode of food poisoning.7 We subsequently found that the same link between emotional upset and ongoing medically unexplained illness existed for symptoms of chronic fatigue after flu or chronic abdominal pain after hysterectomy. The message: find out what the symptoms represent in terms of memory and meaning.   

IBS is an illness in the true sense of the word; an illness of mind, body and meaning. Resolution requires that all three need to be addressed. You might say that for a physical illness that exists at the level of the idea, you need to apply a treatment that operates at the same level.  

Physical treatments for IBS work at the level of the belief. As many clinical trials have demonstrated, it is so difficult to establish an effective treatment for IBS by randomised, placebo-controlled clinical trials because the placebo reactivity is so high. The best placebos are those that have some evidence to support them and carry a strong message. "Take the good bugs to knock out the bad." "Take fibre to strengthen (the moral fibre of) the gut." Arguably, the most effective treatments for IBS - antidepressants, hypnotherapy and cognitive behavioural therapy - act to influence the belief itself.

But there is no magic bullet. Neither is there any need for the dark arts of psychoanalysis.  All that is required is a willingness to listen carefully and help the patient understand the meaning of what they are communicating through their symptom narrative and then offer support and a meaningful combination of cognitive adjustments, life changes and physical treatments that may help them recover.   

Twenty years ago, two young women who suffered from IBS, Sue Backhouse and Christine Dancey, launched the IBS Network as a network of self-help groups to help people learn how to manage their condition themselves. The organisation grew to distribute its own self-help magazine, Gut Reaction, to offer professional advice via a telephone helpline and emails, operated by IBS specialist nurses and doctors, and to publish its unique Self Management Programme supported by a full set of fact sheets. The IBS Network was rebranded as The Gut Trust but in 2011 is being relaunched as the IBS Network to underline its specific commitment to people with IBS. 

At just £24 for year, the IBS Network is an important resource of information, advice and support for doctors and practice nurses to help people with IBS manage their condition themselves. Do encourage your patients to join (www.theguttrust.org or call Kirsty on 0114 272 3253).

References

  1. Longstreth GL, Thompson WG, Chey WD, Houghton LA, Mearin F, Spiller RC. Functional bowel disorders. Gastroenterology 2006;130:1480-91.
  2. García Rodríguez LA, Ruigómez A, Wallander MA, Johansson S, Olbe L. Detection of colorectal tumor and inflammatory bowel disease during follow-up of patients with initial diagnosis of irritable bowel syndrome. Scand J Gastroenterol 2000;35(3):306-11.
  3. Ford AC, Chey WD, Talley NJ, Malhotra A, Spiegel BM, Moayyedi P. Yield of diagnostic tests for celiac disease in individuals with symptoms suggestive of irritable bowel syndrome: systematic review and meta-analysis. Arch Intern Med 2009;169(7):651-8.
  4. Summerton CB, Longlands MG, Wiener K, Shreeve DR. Faecal calprotectin: a marker of inflammation throughout the intestinal tract. Eur J Gastroenterol Hepatol 2002;14:841-5.
  5. Read NW. Sick and Tired; Healing the illnesses, doctors cannot cure. Weidenfeld and Nicolson; 2005.
  6. Gwee K, Leong Y, Graham C et al. The role of psychological and biological factors in postinfective gut dysfunction. Gut 1999;44:400-6.