Celiac disease is a condition where the body reacts negatively to gluten. Gluten is a protein found in foods made from wheat, barley, and rye. To properly diagnose celiac disease, doctors need to understand the changes happening in the body, especially within the intestines. They do this by looking closely at tiny samples from the intestine under a microscope.

Key Changes in the Intestines

1. Villous Atrophy:

   • This is the most important change in celiac disease. The villi are small, finger-like structures that line the intestines and help absorb nutrients. In celiac disease, these villi get flattened or shrunk. When the villi are not healthy, there is less surface area to soak up nutrients.

2. Crypt Hyperplasia:

   • When the intestines try to heal from damage caused by gluten, the crypts (small dips in the intestinal lining) become larger and more numerous. This increase is the body's way of trying to make up for the lost villi.

3. Intraepithelial Lymphocytosis:

   • This means there are more immune cells called lymphocytes in the lining of the intestine. Normally, there aren’t many of these cells. But in celiac disease, their numbers can go up to more than 30 for every 100 cells in the lining. This shows that the body is fighting against the disease.

How Celiac Disease is Diagnosed

Doctors follow a few steps to find out if someone has celiac disease:

• Blood Tests: Before taking a sample from the intestine, doctors will often do blood tests to check for certain antibodies, like anti-tissue transglutaminase (tTG) or anti-endomysial antibodies (EMA). If these tests come back positive, it might mean celiac disease is present.

• Intestinal Biopsy: If the blood tests suggest celiac disease, the next step is to take a small piece of tissue from a part of the intestine called the duodenum. A specialist will look at this tissue under a microscope to see the changes we talked about.

• Scoring the Changes: Doctors use a system called the Marsh classification to rate how bad the changes are:

  • Marsh I: There are more lymphocytes than normal.
  • Marsh II: The crypts are enlarged.
  • Marsh III: The villi are flattened, and this can be graded as A, B, or C based on how serious it is.

Conclusion

In short, looking at the changes in the intestines is very important for diagnosing celiac disease. By examining biopsies that show villous atrophy, crypt hyperplasia, and intraepithelial lymphocytosis, doctors can confirm the diagnosis and understand how severe the disease is. Knowing these details helps in figuring out the right diet and treatments for people with celiac disease, which is essential for their health and well-being.