Coeliac disease: a condition often under diagnosed

Recent studies conducted in China have given lie to earlier beliefs and shown that the illness is in fact not infrequent in Asia especially where wheat is regularly consumed but often remains undetected due to low screening and poor awareness in the local population. The incidence of CD is on the rise all around the world and is thought to be related to higher gluten content in many processed foods as well as to more frequent screening. 

Often an inherited condition, CD is caused by an abnormal immune reaction (known as autoimmune disorder) that is triggered by eating gluten protein mainly found in wheat, rye and barley and also in various prepared foods. The harmful antibodies produced by the immune system lead to a serious inflammation of and damage to the inner lining of the small intestine causing meagre absorption of foods (malabsorption syndrome) and multiple nutritional deficiencies. The exact cause of the immune problem is not known. 

The reduced absorption of essential nutrients, vitamins and minerals associated with the chronic bowel inflammation result in an important variability of symptoms that can and do make CD difficult to diagnose. 

The illness can affect anyone at any age but is usually discovered among young children after they complain of recurrent abdominal discomfort and bloating, diarrhoea, tiredness, joint pains and weight loss, all of which can impact on the child’s growth and development. 

In adults, the typical symptoms are chronic diarrhoea and weight loss but some people may have constipation and be overweight. Most people with CD present non-specific manifestations that include persistent weakness and lack of energy, headaches, bone and joint pains, numbness and tingling in the hands and feet, irritable bowel syndrome, abnormal menstruation and itchy rash. As the condition is frequently misdiagnosed or even labelled a psychological problem, the worsening nutritional disorder may trigger severe iron-deficiency anaemia and very low blood levels of calcium and vitamin D leading to lower bone mineral density with higher risk for brittle bone. 

Relevant blood tests reveal the impaired intestinal absorption as well as the dangerous low levels of essential minerals and vitamins. A tTG-IgA test is then conducted to search for the damaging antibodies. A high level of these antibodies strongly suggests CD and rules out other illnesses but an endoscopy procedure along with a biopsy of the intestine wall is needed to confirm the disease and assess the extent of intestinal lesions.

Some people develop a milder gluten disorder known as gluten sensitivity. They experience similar symptoms but without intestinal inflammation and without the tTG-IgA antibodies found in coeliac disease.

CD needs to be detected and treated early to prevent or minimise long-term complications that may cause damage to the pancreas, neurological disorders, infertility, development of malignancies (cancers) within the intestine and other immune disorders affecting the thyroid, the liver, the colon, the skin or the nerves. The older the patient when the diagnosis is made, the higher the risk of developing another autoimmune illness. 

People who present symptoms suggestive of CD should not try a gluten-free diet before seeking medical advice because the testing for antibodies might then give an incorrect negative result.

Once the diagnosis is made, sticking to a strict gluten-free diet rapidly improves the condition for the vast majority of people and allows the recovery of bowel lining within a few months. Around 5 per cent of patients may still experience symptoms and might be given steroids or immunosuppressants to control the inflammation. When adhering to a lifelong gluten free diet, most people with CD can enjoy a good quality of life as well as normal life expectancy. 

People who suffer from unexplained and recurrent intestinal discomfort with other puzzling symptoms should seek medical advice from a gastroenterologist to possibly be screened for CD.

 

Dr Gerard Lalande is managing director of CEO-Health, which provides medical referrals for expatriates and customised executive medical check-ups in Thailand. He can be contacted at [email protected].