Celiac Disease Biopsy Explained – Part II

This article provides more detail on what the intestine looks like under the microscope in celiac disease and gluten sensitivity. The terms intraepithelial lymphocytosis and crypt hyperplasia are defined and explained for those who want to know what doctors look for when a biopsy of the small intestine is recommended during the evaluation of possible celiac disease.

Celiac disease biopsy: What is crypt hyperplasia and intraepithelial lymphocytosis?

Crypts may enlarge (crypt hyperplasia) in response to the stimulus of injury or the perceived threat of invasion of the body. White blood cells called lymphocytes are activated and sent from the crypt areas to the tips of the villi. This results in what is called intraepithelial lymphocytosis or increased intraepithelial lymphocytes (IEL). This is the hallmark of celiac disease and the first sign of gluten sensitivity. However, it is not specific for celiac disease or gluten sensitivity.

Celiac Disease Biopsy: What Is Considered a Normal IEL Number?

More than 30 years ago, the standard limit for IELs was 40 per 100 enterocytes (or 8/20 enterocytes). More recently, that standard has been lowered to 30 per 100 (6/20), although the literature has recently suggested that the number should be as low as 25 per 100 (5/20). Other studies have reported that potential celiac disease should be suggested by an average of more than 9 to 12 lymphocytes per villus tip in 5 villi. Lymphocytes are sometimes difficult to see or count, so special stains are needed or indicated. These stains stain the particular type of lymphocyte that is activated in celiac disease, allowing them to be seen and counted quite easily. This can also be helpful when someone has already restricted gluten in their diet or started a gluten-free diet before the biopsy.

Celiac Disease Biopsy: What Does Gluten Sensitivity Look Like on Biopsy?

Symptoms of gluten sensitivity may be present and improve on a gluten-free diet in people with normal blood tests and normal intestinal biopsies. If the celiac blood tests are negative or normal, the biopsy is usually normal. However, this is not always the case and some people with true celiac disease have a classic celiac biopsy with normal blood tests. Furthermore, early celiac disease is characterized by more subtle changes on biopsy, and in this setting, blood tests are often negative. Also, some biopsies may appear normal under the microscope, but with special stains or electron microscopy they are not normal and show signs of gluten sensitivity or lesions.

These people may have early celiac disease and are often sensitive to gluten. Therefore, we are sometimes left with a problem of semantics. Gluten sensitivity with normal blood tests and biopsies that responds to a gluten-free diet is well recognized. However, a clear definition for this is not widely accepted. Some people labeled as gluten sensitive are people who have early celiac disease in which there has not been enough damage to the intestine to result in elevated or positive blood tests and/or they do not have changes characteristic of gluten injury in the gut. small intestine biopsy. Others, particularly those without DQ2 or DQ8, appear not to be at significant risk of true celiac disease but respond favorably to a gluten-free diet.

Celiac Disease Biopsy: Who Needs a Biopsy?

If you have suggestive symptoms, a family history, or risk factors for celiac disease, you should have a complete blood test AND a biopsy of the small intestine before starting a gluten-free diet. This will determine if you have specific blood tests and a characteristic diagnostic biopsy. Genetic testing for DQ2 and DQ8 can determine if you are a carrier of any of the major genetic patterns present in more than 98% of people with celiac disease, but their presence does not confirm celiac disease (30-40% of people are carriers). of one or both genes in celiac disease). USA) nor does its absence exclude gluten sensitivity or a remote possibility of celiac disease.