Experts have used magnetic resonance imaging (MRI) to better understand the impact a gluten-free diet has on people with celiac disease, which could be the first step toward finding new ways to treat the disease.
The MARCO study – Magnetic resonance imaging in COliac disease – which is published in Clinical Gastroenterology and Hepatology (CGH), was led by experts from the University of Nottingham School of Medicine, together with colleagues from the Quadram Institute.
Celiac disease is a chronic disease that affects approximately one person in 100 in the general population. When people with celiac disease eat gluten, which is found in pasta and bread, their immune system produces an abnormal reaction that inflames and damages intestinal tissue and causes symptoms such as abdominal pain and bloating.
The only treatment is a lifelong commitment to a gluten-free diet, which helps intestinal tissue recover but still leaves many patients with gastrointestinal symptoms.
Luca Marciani, professor of Gastrointestinal Imaging at the University, led the study. He said: “Despite being a common chronic disease, we still do not know precisely how celiac disease affects the basic physiological functioning of the gut and how treatment with a gluten-free diet can change this further.
“We launched the MARCO study to try to address this issue by using MRI along with gut microbiome analysis to give us new insights into how a gluten-free diet affects people with celiac disease.”
The team recruited 36 people who had just been diagnosed with celiac disease and 36 healthy volunteers to participate in the study. MRI images of their intestines were taken, along with blood and stool samples. The patients then followed a gluten-free diet for a year and returned to repeat the study. Healthy participants also returned a year later and repeated the study, but did not follow any dietary treatment.
The study found that patients newly diagnosed with celiac disease had more intestinal symptoms, more fluid in the small intestine, and that food transit through the intestine was slower than in healthy controls.
The microbiota (the ‘bugs’ that live in the colon) of the patients showed higher levels of ‘bad bugs’ such as E.coli. After a year of a gluten-free diet, intestinal symptoms, intestinal water and intestinal transit improved in the patients, but without returning to normal values. In contrast, the gluten-free diet reduced some of the “good bugs” in the microbiota, such as bifidobacteria associated with a reduced intake of starch and wheat nutrients, due to the different diet.
The patient study was carried out by radiologist Dr Carolyn Costigan, from the University of Nottingham Hospitals, as part of her PhD studies at the University of Nottingham.
Professor Marciani said: “It was particularly interesting to see how the imaging results on gut function correlated with changes in the ‘bugs’ of the colon microbiota. The findings increase our understanding of gut function and physiology in the colon. celiac disease and open the possibility of developing prebiotic treatments to reverse the negative impact of the gluten-free diet on the microbiome.
Dr Frederick Warren of the Quadram Institute said: “This study is the result of an exciting and innovative research collaboration bringing together medical imaging technology and gut microbiome analysis. We provide important information that paves the way for future studies that may identify approaches novel to relieve long-term symptoms in celiac patients.”