Diagnosing Coeliac Disease Updated 2021

Diagnosing Coeliac Disease Updated 2021

Understanding Coeliac Disease

Coeliac disease is an autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. It affects approximately 1 in 100 people in the UK, although many remain undiagnosed. The only current treatment is a strict, lifelong gluten-free diet.

Recognising Symptoms

Symptoms of coeliac disease can vary widely among individuals and can affect any area of the body. Common symptoms include gastrointestinal problems such as diarrhoea, abdominal pain, and bloating. Non-gastrointestinal symptoms may include fatigue, anaemia, osteoporosis, and skin rashes. Because of this variability, coeliac disease can often be misdiagnosed or remain undiagnosed for years.

Initial Screening: Blood Tests

The first step in diagnosing coeliac disease typically involves blood tests that check for specific antibodies. The most common tests include:

• Tissue transglutaminase antibodies (tTG-IgA)
• Endomysial antibodies (EMA-IgA)
• Deamidated gliadin peptide antibodies (DGP-IgA and DGP-IgG)

It's important to note that patients should continue consuming gluten while these tests are conducted to avoid false-negative results. If these blood tests suggest coeliac disease, further diagnostic steps are recommended.

Confirmatory Diagnosis: Biopsy

If initial blood tests are positive, the next step is typically an endoscopic biopsy of the small intestine, conducted by a gastroenterologist. During this procedure, small tissue samples are taken from the lining of the small intestine to look for damage to the villi, which are the small, finger-like projections that absorb nutrients. If villous atrophy is observed, a diagnosis of coeliac disease is confirmed.

Genetic Testing

Genetic testing for HLA-DQ2 and HLA-DQ8 genes can support the diagnosis, although it is not definitive, as these genes are present in about 30% of the UK population. However, a negative result for these genes can effectively exclude coeliac disease as a diagnosis.

Post-Diagnosis: Management and Follow-Up

Once diagnosed, patients must adhere to a strict gluten-free diet, eliminating all sources of wheat, barley, and rye. Follow-up care is crucial to monitor the patient’s response to the diet, usually involving periodic blood tests to check for nutrient deficiencies and whether the coeliac-specific antibodies have returned to normal levels.

Conclusion

Early and accurate diagnosis of coeliac disease is essential to prevent long-term health complications. If you suspect you have coeliac disease, consult your GP who can guide you through the necessary diagnostic procedures. Awareness and understanding of coeliac disease have significantly improved in the UK, contributing to better patient outcomes.