A couple of years ago, I convinced myself that I had irritable bowel syndrome. It joined a rather long list of conditions I’ve diagnosed myself with over the years since medical school. Sometimes I’ve been on the money with self-diagnosis; but on occasions, I’ve jumped to conclusions too soon, or misread the situation.
And, as doctors can do with their own health, I got it wrong.
For fear of putting you off your cornflakes, I’ll spare you the finer details. But what I got wrong was rather more interesting than the symptoms themselves. I’d become so convinced of the diagnosis because I was initially unwilling (and perhaps too stubborn) to consider anything else.
I dutifully went for a second opinion – and a series of tests revealed nothing at all sinister. Nor was it irritable bowel syndrome, better known as IBS, in the end. The difficulty is that there’s no single diagnostic test that can confirm IBS. Instead, doctors make a diagnosis based on patients exhibiting the characteristic symptoms, whilst other tests are used to rule out other potential conditions.
But what struck me was how readily I had convinced myself of the diagnosis, whilst overlooking other plausible possibilities. Therein lies the problem with IBS – it can frequently be mistaken for other conditions and these, in turn, can also be mistaken for IBS. Some of these alternatives are relatively harmless, whilst others are considerably more serious.
To understand this nuance, it’s perhaps best to understand what IBS is. And, just as importantly, what it isn’t.
IBS doesn’t look the same in everyone
IBS is a chronic condition – by nature, symptoms will persist or recur over time. Typically, symptoms come and go, with variable amounts of time between flare-ups.
Its main defining feature is abdominal pain or discomfort – taking into account that patients can experience or describe symptoms in many different ways. Some patients will also notice that the pain is relieved by opening their bowels, but it can also be associated with changes in either the frequency or consistency of the stool. There is a whole spectrum of different stool consistencies in IBS – some people tend more towards diarrhoea, for others constipation dominates. And some people can fluctuate between the two.
Other gut symptoms can point towards IBS – many patients experience an urgent need to rush to the toilet, and have to strain when they get there. They may also notice a lingering sensation of not having emptied their bowels properly, and may notice excess mucus in the toilet pan, or bloating. Sometimes, symptoms are also made worse by eating and may cause nausea or indigestion.
What’s particularly frustrating is that we don’t fully understand what causes IBS. Several suggestions have been proposed, including changes in the way the gut moves and processes food, a heightened sensitivity of the nerves which govern the bowel, and alterations in the bacterial composition – the gut microbiome. Since the condition is associated with stress, it’s very likely that some sort of disconnect between gut and brain is occurring.
It’s not just about the gut
The most prominent symptoms of IBS naturally involve the gut. But IBS patients can also notice a surprising range of other symptoms elsewhere, coming from other organs that might seem totally unrelated.
One example is from the bladder. There is considerable overlap between IBS and functional bladder disorders – whose underlying causes are also poorly understood. Patients may find themselves needing to pass urine more frequently, both during the day and at night, or experience sudden urgency in needing to get to the toilet and only producing small volumes or again feeling that they’re only partially emptying the bladder. Pain in the lower abdomen or pelvis can occur, too – and some women may even notice pain during sex.
You can see that many of these symptoms are similar to the typical bowel symptoms: pain, frequency, urgency. It implies that both bowel and bladder are overactive or irritable – and since both share similar complex nerve pathways, it makes sense.
Put together, these findings could easily be mistaken for something like a urinary tract infection, another very common diagnosis. I’ve seen patients who were treated with recurrent courses of antibiotics for suspected infections that subsequently turned out to be unnecessary. This is why checking a urine sample and sending it to the lab for analysis is important to tell between the two diagnoses – and guide the correct treatment.
And urinary symptoms aren’t the only associated cluster. Co-existent changes in mood and cognition are also common – including depression, anxiety and brain fog. Sleep can suffer too; and persistent tiredness and lack of energy can add additional burden. Patients can also experience backache, muscle aches and joint pain, sometimes affect multiple regions of the body.
It’s not that all these wider symptoms are caused by an irritable gut per se, rather they are recognised common associations, which may share related mechanisms. Noticing them can help paint a clearer diagnostic picture.
IBS can mimic other conditions – and other conditions can mimic IBS
IBS really knows how to play the imitation game. We’ve seen how its associated symptoms can be mistaken for a UTI, but this is just the tip of the iceberg.
Abdominal or pelvic pains can overlap with gynaecological conditions like endometriosis or pelvic inflammatory disease, which is often caused by a sexually transmitted infection (STI). Thyroid gland disorders can also produce a variety of the same symptoms too, including changes in bowel habit.
Inflammatory bowel disease typically causes changes in bowel habit, with diarrhoea and abdominal pain – as can coeliac disease, lactose intolerance, and pancreatic disorders. Colorectal cancer can also alter bowel habits over time.
But the imitation game works both ways – and any of these conditions could also be mistakenly labelled as IBS.
So, how do we tell? There are some red flags to watch out for.
Rectal bleeding should never be attributed to IBS, nor should unexplained weight loss or persistent change in someone’s usual bowel habits. Such findings should definitely prompt a visit to your GP, and not assume it’s due to IBS.
Another useful port of call for investigating these symptoms is a series of blood tests: checking for anaemia, iron deficiency or markers of inflammation, alongside testing for thyroid or coeliac disease. Doctors may also check a urine or stool sample, or send swabs to exclude an STI. Further down the line, investigation with a camera endoscopy might be required in some patients to examine the gut in more detail.
Age is another important consideration. Whilst IBS is common and can technically appear at any age, the likelihood of more serious conditions, including bowel cancer, increases with age. This makes new or persistent changes particularly important to investigate in later life. In women, ovarian cancer can also produce some of the same symptoms as IBS – bloating, abdominal discomfort, changes in bowels and urination – and is again associated with increased age (especially after 50), and a positive family history. Get checked out with a doctor if this is the case.
It’s not all about fibre
IBS has somehow developed a strong association with fibre intake: that patients with it aren’t eating enough fibre, or eating the wrong kinds. Whilst soluble fibre foodstuffs (such as oats) are likely to benefit those in whom constipation is the more prominent symptom, fibre can often exacerbate IBS symptoms, like bloating and wind. It’s often better to limit amounts in your diet (as well as certain foods like wholemeal products, cereals and grains which contain insoluble fibre), aiming to strike the right balance.
Building a steady routine can often help. It’s a good rule of thumb to keep to regular mealtimes, giving yourself enough time to chew, digest and ruminate rather than rushing, and avoid skipping meals. Keeping a diary can also help identify foods which exacerbate symptoms.
General lifestyle measures also make a difference. Staying hydrated, keeping active and stress-busting methods like meditation or yoga could also help reduce gut irritability.
For some patients, additional treatment is required to reduce the severity of symptoms. Medications can be used to treat gut spasms, relieve constipation or diarrhoea, and address co-existent problems like depression – which can also sometimes improve the gut symptoms too.
The biggest lesson that comes from examining IBS is that it’s far from straightforward. A condition of great variability, great mimicry, and many unknowns – that can easily lead us astray. That’s why we shouldn’t be making any assumptions with it, even if you’ve been diagnosed with IBS before. Sometimes we can offer reassurance; sometimes further investigation can uncover something quite different.
After all – as I discovered myself – being convinced you have IBS doesn’t necessarily mean that you do.