This would trigger killing of enterocytes by lymphocytes in the epithelium. The villous atrophy seen on biopsy may also be due to unrelated causes, such as tropical sprue, giardiasis and radiation enteritis. While positive serology and typical biopsy are highly suggestive of coeliac disease, lack of response to the diet may require these alternative diagnoses to be considered. Diagnosis
Diagnosis is often difficult and as of 2019, there continues to be a lack of awareness among physicians about the variability of presentations of coeliac disease and the diagnostic criteria, such that most cases are diagnosed with great delay. It can take up to 12 years to receive a diagnosis from the onset of symptoms and the majority of those affected in most countries never receive it.Several tests can be used. The level of symptoms may determine the order of the tests, but all tests lose their usefulness if the person is already eating a gluten-free diet. Intestinal damage begins to heal within weeks of gluten being removed from the diet, and antibody levels decline over months. For those who have already started on a gluten-free diet, it may be necessary to perform a rechallenge with some gluten-containing food in one meal a day over 6 weeks before repeating the investigations. Blood tests
Serological blood tests are the first-line investigation required to make a diagnosis of coeliac disease. Its sensitivity correlates with the degree of histological lesions.
This affects the absorption of nutrients, frequently leading to anaemia.Diagnosis is typically made by a combination of blood antibody tests and intestinal biopsies, helped by specific genetic testing. Making the diagnosis is not always straightforward. About 10% of the time, the autoantibodies in the blood are negative, and many people have only minor intestinal changes with normal villi. People may have severe symptoms and they may be investigated for years before a diagnosis is achieved. Increasingly, the diagnosis is being made in people without symptoms, as a result of screening. Evidence regarding the effects of screening, however, is not sufficient to determine its usefulness. While the disease is caused by a permanent intolerance to gluten proteins, it is distinct from wheat allergy, which is much more rare.The only known effective treatment is a strict lifelong gluten-free diet, which leads to recovery of the intestinal lining (mucous membrane), improves symptoms, and reduces the risk of developing complications in most people. If untreated, it may result in cancers such as intestinal lymphoma, and a slightly increased risk of early death. Rates vary between different regions of the world, from as few as 1 in 300 to as many as 1 in 40, with an average of between 1 in 100 and 1 in 170 people. It is estimated that 80% of cases remain undiagnosed, usually because of minimal or absent gastrointestinal complaints and lack of knowledge of symptoms and diagnostic criteria. Coeliac disease is slightly more common in women than in men.