| The diagnosis of celiac disease is confirmed by a | | | | lymphocytes) in the setting of a positive specific |
| characteristic abnormal appearance of the small | | | | blood test for celiac, symptoms and especially if |
| intestine under the microscope. Flattening of the | | | | supported by presence of DQ2 and/or DQ8 gene |
| normal finger like projections called villi | | | | pattern, is highly suggestive of celiac disease. The |
| accompanied by signs of inflammation is taken to | | | | difficulty comes when the blood tests for the |
| indicate damage or injury from the storage | | | | specific tests are negative or not elevated but |
| protein gluten in wheat and similar proteins in | | | | only the "non-specific" blood tests (anti-gliadin or |
| barley and rye. The small intestine biopsy has | | | | AGA and anti-reticulin antibodies) are elevated. |
| became the gold standard for establishing the | | | | Also, some people with milder forms of celiac |
| diagnosis of Celiac disease or gluten sensitive | | | | have no blood tests abnormal but have classic |
| enteropathy. Before 1960 gluten withdrawal | | | | biopsy findings of celiac and are termed |
| followed by improvement and subsequent | | | | seronegative (blood test negative) celiacs. |
| worsening upon rechallenge was the diagnostic | | | | Celiac disease biopsy: Can the biopsy be normal in |
| criteria. | | | | celiac disease? |
| Early in the 1960's through the 1970's the small | | | | By definition, the biopsy has been considered the |
| intestine was biopsied by having people swallow a | | | | gold standard for diagnosing celiac. However, |
| small metal capsule that was attached to a | | | | recent studies have shown that the biopsy can be |
| suction tube. This was used to suction up tissue | | | | normal in some people with celiac. How can this |
| into the capsule before guillotining off some tissue | | | | be? The pathologist reading the biopsy may |
| once the capsule was confirmed to be in the small | | | | interpret the biopsy as normal based on his or her |
| intestine by x-ray. Now the tissue is obtained by | | | | bias about celiac disease, a failure to appreciate |
| upper endoscopy, the passage of a lighted video | | | | the significance of the presence of IEL's, or |
| scope through the mouth under sedation to the | | | | misuse of the older standard of >40 IEL's per |
| small intestine, where biopsies are obtained with | | | | 100. However, more importantly is the recent |
| cupped forceps. | | | | recognition that normal appearing biopsies may |
| Celiac disease biopsy: What does the pathologist | | | | not be normal. Electron microscopy has revealed |
| look for under the microscope? | | | | ultra-structural abnormalities in apparent normal |
| The small intestine normally has finger like | | | | biopsies of people confirmed to have celiac |
| projections called villi that give it a large surface | | | | disease. Special stains, that include immune labeling |
| area or contact area for absorption. The villi result | | | | of lymphocytes, have also confirmed increased |
| in a shag carpet or terry cloth towel type | | | | numbers of certain types of specific lymphocytes |
| appearance. Lining the outside surface of each | | | | in the villi of intestinal biopsies of people confirmed |
| villous are intestinal cells or enterocytes that | | | | to have celiac. The bottom line is that a normal |
| secrete mucus and absorb fluids, nutrients, | | | | biopsy does not definitively exclude celiac disease |
| minerals like iron, and vitamins like B12. On the | | | | or gluten sensitivity. |
| surface of the enterocytes are digestive | | | | Celiac diasease biopsy: What are other possible |
| enzymes like lactase that digest lactose or milk | | | | causes of biopsy changes that mimic celiac |
| sugar. At the base of the villi are crypts or | | | | disease? |
| circular like collections of intestinal cells. | | | | Cow's milk protein sensitive enteropathy (CMSE), |
| Celiac disease biopsy: What is villous atrophy? | | | | viral or bacterial infections, medications (especially |
| Normally, villi are 3-5 times longer than the crypts | | | | aspirin like arthritis medications e.g. ibuprofen etc), |
| are tall. However, intestinal injury can result in | | | | autoimmune enteropathy, Helicobacter pylori |
| blunting, shortening (partial villous atrophy) or | | | | infection (the stomach ulcer bacteria), AIDs, |
| complete loss of the villi and flattening (villous | | | | common variable immunodeficiency, and |
| atrophy) of the intestinal surface. The shag carpet | | | | lymphoma of the intestine are all possible causes |
| will have bare spots or the terry cloth towel | | | | of small intestine changes that may mimic celiac. |
| becomes like a tee shirt. The result is lack of | | | | However, if you have classic celiac type |
| absorption of nutrients and water resulting in | | | | symptoms, a positive celiac specific antibody |
| weight loss, malnutrition, and diarrhea. | | | | (anti-endomysial antibody or tissue |
| Celiac disease biopsy: What if the biopsy does not | | | | transglutaminase antibody) and a positive |
| show atrophy or partial atrophy? | | | | response to a gluten free diet then celiac is the |
| If the villi are at least 3 times as long as the | | | | likely cause. The likelihood is further increased if |
| crypts are tall then no flattening or blunting of the | | | | you carry one or both of the two major genes |
| villi is present and celiac disease becomes more | | | | associated with celiac disease, DQ2 and/or DQ8. |
| difficult for the pathologist to diagnose without the | | | | Normalization of celiac specific blood tests and the |
| history or blood test results. However, an | | | | biopsy after a gluten free diet confirms the |
| increased number of IEL's (intra-epitheliel | | | | diagnosis of celiac disease. |