Thousands suffer from tabooed disease. New method makes it easier to identify the right treatment

Most people have at some point in their life suffered an intestinal infection or food poisoning forcing them to stay close to the bathroom. It is very uncomfortable. Most of the time, though, it passes quickly.

But around 60,000-100,000 Danes suffer from a form of chronic diarrhoea called bile acid malabsorption or bile acid diarrhoea.

It is a chronic condition characterised by frequent and sudden diarrhoea more than 10 times a day. Even though the disease is not life-threatening, it can seriously affect the patient’s everyday life, especially their social life, and be extremely disabling.

“You have to rush to the bathroom several times a day. Therefore, keeping a job or maintaining social relations can be difficult, and a lot of people isolate themselves. The disease controls their life,” says Professor Jesper Bøje Andersen from the Biotech Research & Innovation Centre.

He and his research group and clinical cooperation partners at Herlev and Gentofte Hospital headed by Professor and Consultant Doctor Filip Krag Knop are responsible for a new study, which provides new ways of diagnosing bile acid diarrhoea and identifying the most effective treatment for the individual patient.

“A lot of people with chronic diarrhoea don’t realise that they suffer from bile acid diarrhoea and what has caused it. This is a result of lack of knowledge among healthcare workers and the relatively complex and expensive – and for the patient difficult – process of diagnosing the disease,” says Filip Krag Knop.

Jesper Bøje Andersen adds:

“We have developed a new concept which may be used to diagnose the disease based on a simple blood sample. Today, diagnostics involves radiopharmaceuticals, which means that there is a radiation risk. The process is not necessarily dangerous, but unpleasant and arduous, and not all countries in the world support the method, including the US.”

The new method means that doctors should be able to determine whether the patient has bile acid diarrhoea based on a simple blood sample. They focus on molecules known as metabolites in the blood.

“A blood sample contains lots of different metabolites. Right now we are able to identify almost 1,300 different metabolites, and around a handful of these can be used to diagnose bile acid diarrhoea. The metabolites of bile acid diarrhoea patients form a particular pattern that makes them recognisable,” says Jesper Bøje Andersen.

Which treatment?

The researchers analysed blood samples from 50 patients and they quickly realised that the samples – and patients – could be divided into two groups.

“First, we did not understand why. All the blood samples had been taken before treatment, typically at the time of diagnosis,” says Jesper Bøje Andersen.

The patients then participated in a randomised clinical study at the Center for Clinical Metabolic Research at Herlev and Gentofte Hospital. Here the doctors studied the effect of two different treatments: the conventional treatment involving bile acid sequestrant colesevelam and a new treatment involving liraglutide, which is normally used to treat type 2 diabetes and severe overweight.

“What is interesting is that the metabolites in the patients’ blood divided them into two groups: one that responds well to colesevelam and one that responds well to liraglutide. This suggests that we should be able to say which treatment is the most effective by analysing the patient’s blood at the time of diagnosis,” says Jesper Bøje Andersen.

The clinical study showed that colesevelam treatment eased the bile acid diarrhoea symptoms of 50 per cent of the patients, while liraglutide treatment eased the symptoms of 77 per cent of the patients.

Jesper Bøje Andersen, Filip Krag Knop and their research groups hope the new study will benefit the 60,000-100,000 Danes who suffer from bile acid diarrhoea.

The majority of cases of bile acid diarrhoea is diagnosed at a very late stage or never diagnosed at all.

“Around 40 per cent of the patients suffer from this condition for up to five years before it is diagnosed. Of course, this may be because they do not realise that it is a disease and that it can be treated. But it may also be because chronic diarrhoea is a tabooed disease,” says Filip Krag Knop.

You can read the study, “The Serum Lipidome Unravels a Diagnostic Potential in Bile Acid Diarrhea”, in Lewinska & Kårhus et al., GUT.

About bile acid diarrhoea

When we eat high-fat food, the gallbladder releases bile acid. Bile acid helps the body absorb fat and fat-soluble vitamins from the food. Around 98 per cent of the bile acid is absorbed by the small intestine and returned via the blood to the liver. If the body either produces and/or releases excessive amounts of bile acid or if the bile acid is not reabsorbed by the blood, a large amount will end up in the large intestine. Here it will result in irritated mucosa, lack of fluid in the intestines and increased intestinal movements, all of which create symptoms of bile acid diarrhoea.