Exams and Tests
In many cases of
celiac disease,
other conditions with similar symptoms, such as
food intolerance or
irritable bowel syndrome, are first suspected. Often,
celiac disease is only considered after the initial diagnosis of another
condition is rejected because treatments are not effective.
A
medical history and physical examination and lab tests
often point to celiac disease. The diagnosis is confirmed with a small
intestine
biopsy collected during an
endoscopy. For this procedure, an endoscope is guided
down a person's throat to the small intestine.
Blood antibody tests
Celiac disease triggers the
immune system to produce certain
antibodies. If celiac disease is suspected, your
doctor will order certain blood tests to detect and measure specific
antibodies.
- IgAtTG: Immunoglobulin A (IgA) and tissue
transglutaminase (tTG) antibody
- IgAEMA: Immunoglobulin A (IgA) and
antiendomysial antibody (EMA)
If either or both of these tests are positive, your doctor
may perform a
biopsy of the small intestine to confirm a diagnosis
of celiac disease.
Endoscopy
A biopsy taken during an
upper gastrointestinal endoscopy may be done to
confirm celiac disease after antibody tests are positive. Sometimes a biopsy
detects celiac disease when a person is being tested for another
condition.
A biopsy should be done when you or your child is
eating a diet that includes gluten. If the biopsy shows signs of celiac disease
(such as abnormal villi and inflammation in the
small intestine), a
gluten-free diet will be recommended. If the symptoms
go away on the gluten-free diet and antibody tests are normal, a diagnosis of
celiac disease is confirmed.
If you or your child is on a
gluten-free diet before a biopsy is done, you may have to eat a prescribed
amount of gluten before the test.
Other tests
Tests for malabsorption may be done
when celiac disease is suspected. These tests may include:
- A
stool analysis to evaluate fat content. A 3-day
collection of stools usually shows higher-than-normal fat content in people who
have celiac disease that is causing symptoms.
- A
bone density test. This may be done to see if you have
problems such as
osteomalacia or
osteoporosis, which may develop in some people with
celiac disease.
- An
upper GI series, which may detect intestinal problems
but does not give precise information to guide diagnosis or treatment for
celiac disease. An upper GI series is rarely needed when celiac disease is
suspected.
Certain blood tests may be done to evaluate complications
from celiac disease. For example, a
complete blood count (CBC) may be done to test for
anemia; also, a
chemistry screen, which tests a blood sample for
sodium, potassium, chloride, and carbon dioxide levels, may be done to identify
whether you or your child has an
electrolyte imbalance.
If a diagnosis of
celiac disease is suspected but symptoms don't improve with a gluten-free diet,
further testing for
other conditions and diseases, such as
Crohn's disease or
cystic fibrosis, may be needed.
Prepare your child for exams and tests
that are needed to diagnose suspected celiac disease. Doing so will help your
child understand what to expect and can help reduce fears.
Early Detection
Blood tests to measure
antibodies, such as immunoglobulin A tissue
transglutaminase (IgAtTG) or the immunoglobulin A antiendomysial antibody
(IgAEMA), can be useful screening tools for people who are at increased risk
for having celiac disease. This includes people with a family history of celiac
disease or those who have
type 1 diabetes,
Down syndrome,
dermatitis herpetiformis, an
autoimmune disease, unexplained
anemia, or unexplained
osteoporosis. Talk to your health professional if you
think you or your child should be screened for celiac disease.