9.0 Making a Diagnosis with Bloating and IBS

In the “old days” IBS used to be called a "diagnosis of exclusion” - i.e. what is left behind when every other condition has been ruled-out. Nowadays, it is very much a “positive” diagnosis because we know a lot more about it and more importantly, we know how to treat it.

Because many things can cause bowel upset, bloating or tummy pain and because there is no single, definitive test for Bloating and IBS, it is important to be careful about getting the diagnosis right. No test, No diagnosis!

9.1 First ask the right questions about Bloating and IBS

This is not an exhaustive list but should give you some direction as to what needs to be mentioned to your doctor.

We need to be realistic about symptom details. The symptoms of IBS can change with time and it can be like trying to pin down a shadow. So, just look at things over the past few weeks or couple of months. If you're not sure about the answer, think in terms of "...on balance..."

9.1.1 The questions

• How long has the problem been going on for? Anything like this in the past?

• What is the main or key symptom (Diarrhoea, Constipation, Constipation and Diarrhoea? With Bloating or Gas?

• If Constipation, is there any straining on using the toilet? Feel a lump "coming down"? Feel not quite empty? Just never have any urge to go to the loo? Need to use a finger to help things come out? (Horrible questions, but still important!)

• Any Pain/Discomfort?

• Was there a definite starting point (food poisoning, overseas trip, giving birth, course of antibiotics or new medications, a recent illness)?

• What is your medical history (previous operations, conditions)?

• Is there a family history of particular bowel conditions or cancer (bowel/ovary)?

• What medications or supplements etc are you taking?

• Have you changed your Diet- especially, have you gone to a “Clean” or “Healthy” Diet?

• Has your doctor or nurse performed a physical examination?

9.2 Standard Tests (needed by Everyone) for Bloating and IBS

Why have tests? The problem is that all the things that go wrong in the bowel share the same symptoms. Think about it, how many ways are there for our guts to say that they're not happy? Pain, diarrhoea.... Trying to apply logic, or Googling lists of things that can cause similar symptoms just doesn't work (and can be dangerous).

The tests that we are going to talk about here are all about making sure that there isn't anything specific going on such as gluten allergy (coeliac disease), bowel inflammation etc. There are other diagnostic tests that can be done. These look at the less common causes of bowel upset, but again those are not for now; they are reserved for if things are not settling down. We go through those more specific and specialized tests on the pages dedicated to specific symptoms such as Diarrhoea, Constipation etc. Tests for food intolerances are also not part of this first section because they don't give a diagnosis, rather they just tell us how to focus the treatment if it does turn out to be IBS. Again, we talk about these elsewhere.

The tests for now come in two parts: those that "Everyone" needs and then a few extra bolt-on ones that are decided on by your Specific symptom, whether that be Diarrhoea, Constipation or Lower tummy pain. If you have all of these, by the way, you do all the tests.

One important "house-keeping" point before we get on with things. If any of the following symptoms or points rings true for you, do tell your doctor:

- Blood with passing a bowel motion (even if just a bit of bright red blood on the toilet paper).

- Lower tummy/pelvic pain or bloating that is there all the time.

- Weight loss that you cannot explain.

- A family history of bowel or ovary cancer.

So, what are these tests for “Everyone” with Bloating and IBS?

- Blood tests: Full blood count (“FBC” or “CBC”); Kidney and Liver profiles; Thyroid function; C-Reactive protein and Coeliac screen.

- Stool samples: Faecal calprotectin; qFIT (checks for “hidden” blood).

9.2.1 Notes on “Everyone” Tests for Bloating and IBS

- Coeliac blood test: only accurate if there has been enough gluten in your diet for 6 weeks before the test (equivalent to about two slices of normal bread each day). If you've been on a gluten free diet, there is no point in doing the test without changing your diet back.

- Faecal calprotectin: a simple stool sample test that is being used more and more as a "non-invasive" substitute for "tube/camera" tests. It checks for lower bowel inflammation and other conditions. It's a very good test. Another similar test is Faecal lactoferrin which is much the same as the calprotectin one.

Let's talk about what the calprotectin result might mean:

• A "normal" calprotectin result is very re-assuring for there being nothing specific going on in the lower bowel.

• If the calprotectin test comes back as high (say over 200), the next step may be to have a Colonoscopy. But, actually more often than not, the colonoscopy will be normal!

• If the result is a little "high" (say 50-150), then it often means nothing and is usually repeated. If that comes back as normal, that is OK. But, should it come back as "high" again, a tube test is needed. What doctors do about these slightly high values differs though, so best to discuss it with them.

No test is 100% perfect and this test probably isn't ideal in those over about 40 years of age as it cannot fully exclude other causes of symptoms. But it is good enough for younger people where cancers are unlikely. It should not be used in anyone with a family history of bowel cancer where a relative under the age of 50 years has had this condition and certainly should not be used if there has been any passage of blood.

9.3 Extra tests that are Symptom-specific for Bloating and IBS

- Diarrhoea: If you have been traveling or the symptoms very acute, Culture/sensitivity with (Ova/parasites if you have been anywhere exotic).

- Constipation: Calcium level (blood test)

- Lower tummy pain: CA125 (women only: blood test to check ovaries) and an Ultrasound scan of Abdomen and Pelvis.