Am I dying? This unsettling thought crept into my mind and refused to leave.

I’d spent most of the day confined to my bed, drifting in and out of restless sleep, feeling utterly, dreadfully unwell. The previous day had started with an upset stomach, which then escalated to a persistent headache, coupled with nausea, fatigue, and a fever.

The fever was the most unbearable part. I swung between feeling unbearably hot and drenched in sweat to shivering with cold, sometimes unsure of which sensation I was experiencing. My heart raced at an alarming pace, leaving me breathless and fearful that my end might be near.

I debated whether I should muster the strength to ask my husband, Paul, to take me to the emergency room. However, the mere thought of enduring a four-hour wait there seemed almost worse than any imagined demise.

What I was experiencing turned out to be a flare-up of diverticulitis—a condition I now recognize all too well—but never had I felt so miserably ill.

Diverticulitis occurs when pouches called diverticulae that form in the intestinal walls in the colon become inflamed or infected by a build-up of bacteria. The pouches can be as big as 20mm (three-quarters of an inch) in some people.

Diverticulitis can cause extreme pain – women who suffer from it say it’s worse than childbirth.

In severe cases, an abscess can form and the pouch may burst, which can cause peritonitis (inflammation of the abdomen) or even sepsis, a potentially life-threatening overreaction of the immune system.

By the age of 80 around 70 per cent of people will have diverticulae but most won’t know this as they cause no symptoms. Why the pouches become inflamed and infected in some and not others is not yet known but it becomes increasingly common from the age of 40 as the intestinal wall weakens with age. And it doesn’t help that many of those with diverticulae are given the wrong dietary advice that could even make the problem worse (but more on that later).

The thought of sitting in A&E for four hours or more was, almost literally, writes Nicola Jane Swinney, a fate worse than death

Women who suffer from diverticulitis say it’s worse than childbirth, as the condition can cause extreme pain, nausea and fever

The charity Guts UK says as many as one in two of us will develop diverticulitis and that number is growing. Indeed, hospital admissions for diverticulitis have more than doubled over the past decade, says Professor Bu’Hussain Hayee, clinical director for liver, endoscopy and gastroenterology at King’s College Hospital NHS Foundation Trust.

This is partly because of our ageing population, he says. However, there are other factors, he adds, including obesity (this increases inflammation generally), sedentary lifestyles and a lack of fibre – which both slow the transit of waste through the colon; smoking and certain medications, such as non-steroidal anti-inflammatory drugs; and steroids, as they can cause inflammation in the colon.

Ultra-processed foods have also been implicated, says Professor Hayee – although it’s not clear why.

One problem is that symptoms such as diarrhoea, abdominal pain, bloating, and nausea together with a change in bowel habits and a dull pain in the abdomen – can be mistaken for irritable bowel syndrome (IBS), and some patients suffer with both.

‘There is a significant overlap,’ says Professor Hayee.

Blood in the stool, meanwhile – caused by the pouches bleeding – can be dismissed as piles.

When in 2020, aged 57, I started having bouts of feeling feverish and unwell for days, my GP ordered a range of blood tests to try to find the cause – but they all came back as normal.

During a particularly bad bout in March 2021, I phoned her, and she asked me to go into the surgery. Noting my raised temperature and elevated heart rate she diagnosed diverticulitis and immediately dispatched me to a gastroenterologist at the Princess Royal University Hospital in Bromley, south-east London.

The consultant felt the left side of my abdomen which typically will cause a lot of pain in someone with a diverticulitis flare-up – this is the area of the descending colon, the final part of the large intestine where diverticulae occur.

For reasons that no one has been able to explain, I get very little pain.

Perhaps because I wasn’t in pain, the gastroenterologist decided I didn’t have diverticulitis and so I was sent home.

I could only manage water for days but my symptoms gradually subsided.

It would be after yet another flare-up a couple of months later – the episode when I thought I was dying – that I would finally be sent for a colonoscopy, which revealed multiple diverticulae in my intestinal wall each between 2mm to 10mm in size. This, together with my symptoms, confirmed I had diverticulitis.

Diagnosis is one thing – learning how to manage the condition is another.

And Professor Hayee says there is a lot of misinformation about this.

Many with diverticulitis are still told to avoid high-fibre foods such as peas, beans, apples, bananas, avocados, carrots and barley, but the charity Guts UK these should be added to the diet as they bulk up the stool, hastening its transit and reducing pressure on any pouches in the gut wall.

‘Long-term studies do not link diet as a primary cause,’ says Professor Hayee.

Avoiding fibre is only suggested when complications occur such as when an infected pouch ruptures, allowing waste into the abdominal cavity.

People with diverticulae may also be told – wrongly – to avoid things such as raspberries, strawberries and tomatoes, any other kind of seed, fruit or vegetable skins, popcorn and nuts – again, because it was thought to be these lodged into the pouches. But this has been refuted by multiple studies, including one published in the Annals of Internal Medicine earlier this year.

Separately, some people with diverticulae say they cannot tolerate onions, red meat or tomatoes, for example.

But Professor Hayee doesn’t believe these bring on diverticulitis.

A low-FODMAP (fermentable, oligosaccharides, disaccharides, monosaccharides and polyols) diet is sometimes suggested by some health professionals.

FODMAPS are a form of fermentable carbohydrate found in bread, pasta, breakfast cereals, stone fruit, apples and beans and pulses. In short, the diet is very restrictive.

Julie Thompson, a gastroenterology specialist dietitian and information manager of Guts UK says the low-FODMAP diet can be ‘extremely successful’ in treating IBS, ‘but it is not recommended as a treatment path for those with diverticulitis’.

In fact, says Professor Hayee people with diverticulae can eat a normal diet but are advised to switch to fluids only during a flare-up, and some may need antibiotics to clear the infection.

Those who develop frequent infections or abscesses may be offered surgery to remove the affected part of the gut, with the two ‘ends’ being joined back up – this is reserved for complications such as perforations, frequent infections and abscesses, says Professor Hayee.

I get four or five flare-ups each year – the worst I’ve ever had was in January this year, when I lost 8lbs in four days.

Trial and error has taught me how to manage my condition.

I have a rescue pack of antibiotics in the house, which I go on to when a flare-up reaches the shivering/sweating phase, and I always drink between two and three litres of water a day.

I try to eat more fibre and sometimes take psyllium husk to up my fibre intake. If I have a bout of diarrhoea, I switch to a water-only diet for a couple of days and get as much sleep as I can.

After a flare-up, I find it difficult to start eating again, because I am terrified of setting off the symptoms.

On one occasion, I’d been ill for five days but was starting to feel better and ate a small amount of chicken, carrot and celery.

I spent most of that night in the bathroom – and the following day I was back in bed, sweating and freezing.

Despite what Professor Hayee says I find it better to avoid fibre after a flare-up. As a friend and fellow sufferer puts it ‘eating fibre while the gut is still inflamed is like applying sandpaper to a graze’.

Even when I’m not in a flare-up, I am rarely completely ‘well’; I suffer from fatigue, frequent stomach upsets and often feel nauseous.

But there is a glimmer of hope.

A new treatment is being trialled in which the little pouches are closed surgically. The clips are inserted via an endoscope – a long thin tube – while the patient is under conscious sedation.

Professor Hayee says: ‘My team at King’s have published research that shows clipping is safe and reduces symptoms [of diverticulitis] and IBS, as well as reducing the frequency of diverticulitis episodes.’

The pilot study was published in the journal Gut in 2019 and the full results which Professor Hayee says look ‘very promising’ will be published soon.

For my fellow sufferers and I, it could be the game-changer we have been waiting for.

For more information visit: gutscharity.org.uk and bowelresearchuk.org