Diagnosing Celiac Disease and Gluten Sensitivity

Celiac disease, also known as gluten sensitive enteropathy is very common but frequently missed. It is a autoimmune disease of intestinal damage due to gluten in people who are genetically predisposed. Classic Celiac disease is diagnosed by abnormal blood tests and an abnormal
appearing intestine on biopsy and symptoms that resolve with gluten free diet.

Several blood tests exist for Celiac disease. They have varying degrees of accuracy. Some are more sensitive, meaning they will be positive in milder forms of the disease but are not specific, meaning a positive test may not indicate Celiac disease. Others are felt to be very specific, meaning that when they are positive, it is almost certain you have the disease.

The most specific tests are tests for Celiac disease endomysial antibodies (EMA) and
tissue transglutaminase sntibody (tTG) antibody tests. These two tests are IgA based tests and can be negative if you are deficient in the immunoglobin IgA, which occurs in 10-20% of people with Celiac. When either EMA or tTG are positive Celiac disease is very likely and usually the intestine biopsy is positive. Recent studies indicate that the tTG may only be positive in 40% of true Celiacs when mild degrees of intestine damage are present on biopsy. Seronegative Celiac, meaning the blood tests are negative but the biopsy is positive may occur in up to 20% of Celiacs.

Antibodies for gliadin (AGA), the toxic fraction of gluten are considered very sensitive but not specific for Celiac disease. Newer assays for AGA antibodies for gluten that has undergone a chemical change
called deamidation appear to be more specific for Celiac disease (Gliadin II,
Inova) than the older gliadin tests. They also may be as or more accurate than EMA and tTG
antibody tests but are not yet widely available.

The most distressing problem for people with lesser forms of gluten intolerance who have blood tests and/or biopsies that are normal or borderline yet respond to a gluten free diet is either not be taking seriously or knowing for sure if they are sensitive to gluten. For these individuals stool
antibody testing for antigliadin and tTG have been helpful. Such stool testing has been performed in research labs and published in a few studies but only recently available through the commercial lab, Enterolab. Founded by a former Baylor research gastroenterologist, Dr Ken Fine, the tests are available to order by people online without a doctors order but are not generally covered by insurance. Dr. Fine, who patented the test, has yet to publish the results of his findings in a peer reviewed journal so his tests are not widely accepted. However, his unpublished data and clinical experience of some of us who have used his test have
indicated the tests are very sensitive for signs of gluten sensitivity. He reports that they are 100% sensitive for Celiac disease and highly sensitive
for gluten sensitivity of lesser degrees. In the presence of symptoms that reverse on a gluten-free diet
abnormal stool antibody levels can be found in most people before blood tests or biopsies become
abnormal.

Small intestine biopsies during upper gastrointestinal endoscopy
are considered the “gold standard” for the diagnosis of Celiac disease.
However, recent studies have demonstrated that some people with gluten sensitivity, especially relatives of Celiacs
with little or no symptoms, have changes from gluten injury to the intestine that can’t be seen with normal microscope examination. They can only be seen with special stains not routinely done or with a research electron microscope. The special stains are known as immunohistochemistry stains. They stain specialized white
blood cells called lymphocytes in the intestinal lining tips or villi. When these lymphocytes are increased it is known as intraepithelial lymphocytosis or increased IELs and it is the earliest sign
of gluten induced injury or irritation. Electron microscopy also reveals very early ultrastructural changes in some individuals when blood tests and standard biopsy exmination are normal. When people who have these changes are
offered the option of gluten-free diet they usually responded favorably. In contrast, those who continued to eat gluten often later developed classic Celiac disease.

What these studies suggest is that a “normal small intestine biopsy” may exclude
Celiac disease as defined by strict criteria but it is not a gold standard for detecting gluten sensitivity. This fact is appreciated by many individuals who have respond to a gluten-free diet they start
based on their symptoms, family history, suggestive blood test or stool antibody
test(s).

Another source of confusion is in the genetics of Celiac and gluten sensitivity.
Testing for specific blood type patterns on white blood cells known as HLA
DQ2 and DQ8 is increasingly be employed to determine if a person carries either of the two gene
pattern present in 95-98% of Celiacs and predisposing to development of Celiac disease. Some use the absence of these two patterns
as a way of excluding the possibility of Celiac disease and the need for testing or
gluten-free diet. However, there are rare reports of documented Celiac disease in people who are DQ2 and
DQ8 negative. Moreover, recent studies indicate other DQ
patterns may be associated with gluten sensitivity though unlikely to
predispose to classic Celiac disease.

Testing for all the DQ patterns is advocated by Dr. Fine, based on his
experience with stool antibody test results. He reports the other DQ types are
associated with elevated levels of gliadin and tTG in the stool and symptoms that respond to a gluten-free diet.
According to his unpublished data, all the DQ types except DQ4 are associated with
a risk of intolerance to gluten. Therefore, testing for all the DQ types allows a person to
determine if they carrry one of the two high risk gene types for Celiac disease or the
any of the other “minor DQ” genes Fine has found associated with gluten sensitivity.

Enterolab’s stool testing for gliadin antibodies and tissue
transglutaminase antibodies though not widely accepted, have gained favor in the lay
public’s opinion as an option for determining sensitivity to gluten either despite of negative blood tests and/or biopsies or in place of the more invasive tests. Most doctors still recommend the accepted blood tests and small
bowel biopsy for confirmation of Celiac. Though the reports in the lay community
are overwhelmingly positive they have not been subjected to peer review in
the medical community pending Dr. Fine publishing his data or other researchers reproducing his results.

However, doctors open to
the broader problem of gluten
sensitivity are reporting these tests helpful in many patients suspected of gluten
intolerance. Especially when someone has symptoms consistent with gluten sensitivity but has negative or inconclusive blood tests and/or biopsies these tests may be very helpful though some are not certain
how to interpret the tests. The national Celiac organizations are uncertain about how to
comment on their application without published research though a recent article
in the British Medical Journal did show stool tests highly specific for Celiac. Dr.
Fine’s has publicly commented that his unpublished data demonstrates those with
abnormal stool tests indicating gluten sensitivity
overwhelmingly respond favorably to a gluten free diet with improvement of
symptoms and general quality of life.

Another problem is that there is not universally agreed upon definitions for gluten sensitivity or intolerance. This becomes specially difficult for those who do not meet strict criteria for Celiac disease yet may have abnormal tests and/or symptoms that respond to gluten-free diet. Those individuals become confused when they try to find information but don’t have a formal diagnosis of Celiac disease. Consensus in the medical community on definitions and more research in this area is greatly needed.

The few doctors who appreciate the spectrum of gluten
intolerance or sensitivity are outnumbered by the medical majority that continue to
insist on strict criteria for diagnosis for Celiac disease before recommending a
gluten-free diet. Doctors either unfamiliar with the limitations of the tests as documented by Celiac research or who insist on the
strict criteria for Celiac being the only indication for recommending a gluten free
diet unfortunately may confuse or frustrate gluten sensitive individuals. Some of these people then seek answers on the internet or from alternative practitioners. Many have their diagnosis missed, challenged, dismissed, or are misinformed. As a result they fail to benefit from the health
benefits of a gluten-free diet because they are advised that it is not required based on normal blood tests and/or normal biopsies. In the meantime, Celiac disease and gluten sensitivity continue to be undiagnosed or misdiagnosed. For more information visit http://www.thefooddoc.com.

Dr. Scot Lewey is a physician who is specialty trained and board certified in the field of gastroenterology (diseases of the digestive system) who practices his specialty in Colorado. He is the physician advisor to the local Celiac Sprue support group and is a published author and researcher who is developing a web based educational program for people suffering from food intolerances, http://www.thefooddoc.com

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Why Doctors Frequently Miss Celiac Disease and Gluten Sensitivity

Doctors frequently fail to diagnose a very common condition known as Celiac disease or gluten sensitivity. The average delay in diagnosis is 11 years in adults. There are several reasons for this delay. Celiac disease was once considered to be rare and affect only young children. This is what most doctors practicing today were taught in medical school and they are unaware of how the spectrum of Celiac disease has changed.

Screening blood donors only recently confirmed Celiac disease occurs in 1 in 133 people in the U.S. However, that information most physicians are unaware of this for several reasons.

Celiac disease is treated by a gluten-free diet not a drug. Drug companies subsidize much of the continuing medical education received by doctors and most of the medical research in the United States. Without drug company money and marketing, Celiac disease does not appear in medical journal ads or get mentioned by drug reps detailing doctors. It is rarely a topic of major conferences or research grant proposals. It is a disease that is largely “out of site, out of mind” for most doctors.

Doctors who actually remember Celiac disease envision in their mind a very young, pale, emaciated child with skinny limbs and a big “potbelly” like the picture they were shown years ago in medical school. The medical history linked with this image is a malnourished child that is not growing and has numerous, bulky, and foul smelling diarrheal stools. Surveys of primary care providers have confirmed that most are unaware that Celiac occurs in adults. If they do think it could occur in adults they don’t believe it can occur in someone who is overweight and constipated or has no intestinal symptoms.

They lack awareness that symptoms such as fatigue, bone and joint pain, headaches, and skin rashes are common in Celiac. Most are also it is associated with other autoimmune conditions like thyroid disease, diabetes, rheumatoid arthritis and lupus. Malabsorption complications such as anemia and osteoporosis are often not recognized as common presentations of untreated Celiac disease. Over 250 symptoms involving nearly every part of the body have been reported in Celiac disease. Unless you provide your doctor distinct clues such as a family history of Celiac or mention the possibility that you think you might be gluten senstitive they don’t even consider the possibility of it to be the cause of your being ill.

Many doctors are unfamiliar with the specific blood tests or genetic tests for Celiac disease. Others are not thinking about the possibility of Celiac while listening to your symptoms so they never consider ordering the blood tests. Either way you never have chance of being diagnosed unless you ask them to test you. Even then your request may be ignored unless you insiste because of your family history, advice of family member or friend, or you present to them your own research. Their preconceived biases or misconceptions about Celiac may difficult to break. If you have little to no symptoms you may still may need to be tested because of risk factors but your doctor may be unfamiliar with the indications for screening of high risk individuals.

It should be noted that many doctors don’t like changing a diagnosis they have made and therefore may fail to consider an alternate diagnosis when new symptoms present. Instead they may attempt to fit the new symptoms into an existing condition or diagnosis. Because people with untreated Celiac disease frequently have neuropsychiatric symptoms your doctor may label you depressed, anxious, stressed, neurotic or just plain crazy. As a result they may stops listening or taking your concerns seriously and you may be tempted to stop mentioning your symptoms or concerns.

Lastly, doctors are under tremendous pressure to keep medical costs down. Diagnostic tests are one the biggest expenses in medical care and are ordered by doctors. Many insurance companies track individual doctors according to the number of tests they order. Therefore, your doctors may feel pressured to avoid ordering any perceived “unnecessary tests”. For some doctors who still believe Celiac disease is rare, blood tests or endoscopies required for diagnosis may not be ordered for these reasons. If ordered, however, blood tests may be misinterpreted or falsely negative. Endoscopy may be done but no biopsy performed or poorly interpreted. You and doctor may be under the false assurance that Celiac disease and gluten sensitivity have been excluded.

I recommend you help your doctor if you believe you may have Celiac disease or gluten sensitivity by 1) Writing down all your symptoms and your understanding of how they may be due to gluten sensitivity 2) Sharing your family history, including your ancestry and any genetic tests done 3) Being familiar with the diagnostic tests for Celiac disease and gluten sensitivity and their limitations 4) Politely ask your doctor to test you for Celiac disease pointing out why you believe it may be a cause of your symptoms 5) Being willing to undergo adequate and appropriate evaluation and 6) Being prepared to obtain a second opinion if necessary. Being educated and prepared will help your doctor help you.

Dr. Scot Lewey is a physician who is specialty trained and board certified in the field of gastroenterology (diseases of the digestive system) who practices his specialty in Colorado. He is the physician advisor to the local Celiac Sprue support group and is a published author and researcher. He is developing a web based educational program for people suffering from food intolerance and Celiac disease http://www.thefooddoc.com

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