Question:  How to diagnose Celiac Disease ?
Answer: A health care provider diagnoses celiac disease with
                
- a medical and family history  - a physical exam  - blood tests  - an intestinal biopsy  - a skin biopsy
                
Medical and Family History
                
Taking a medical and family history may help a health care provider diagnose celiac disease. He or she will ask the patient or caregiver to provide a medical and family history, specifically if anyone in the patient's family has a history of celiac disease.
                
Physical Exam
                
A physical exam may help diagnose celiac disease. During a physical exam, a health care provider usually
                
- examines the patient's body for malnutrition or a rash  - uses a stethoscope to listen to sounds within the abdomen  - taps on the patient's abdomen checking for bloating and pain
                
Blood Tests
                
A blood test involves drawing blood at a health care provider's office or a commercial facility and sending the sample to a lab for analysis. A blood test can show the presence of antibodies that are common in celiac disease.
                
If blood test results are negative and a health care provider still suspects celiac disease, he or she may order additional blood tests, which can affect test results.
                
Before the blood tests, patients should continue to eat a diet that includes foods with gluten, such as breads and pastas. If a patient stops eating foods with gluten before being tested, the results may be negative for celiac disease even if the disease is present.
                
Intestinal Biopsy
                
If blood tests suggest that a patient has celiac disease, a health care provider will perform a biopsy of the patient's small intestine to confirm the diagnosis. A biopsy is a procedure that involves taking a piece of tissue for examination with a microscope. A health care provider performs the biopsy in an outpatient center or a hospital. He or she will give the patient light sedation and a local anesthetic. Some patients may receive general anesthesia.
                
During the biopsy, a health care provider removes tiny pieces of tissue from the patient's small intestine using an endoscopea small, flexible camera with a light. The health care provider carefully feeds the endoscope down the patient's esophagus and into the stomach and small intestine. A small camera mounted on the endoscope transmits a video image to a monitor, allowing close examination of the intestinal lining. The health care provider then takes the samples using tiny tools that he or she passes through the endoscope. A pathologista doctor who specializes in examining tissues to diagnose diseasesexamines the tissue in a lab. The test can show damage to the villi in the small intestine.
                
Skin Biopsy
                
When a health care provider suspects that a patient has dermatitis herpetiformis, he or she will perform a skin biopsy. A skin biopsy is a procedure that involves removing tiny pieces of skin tissue for examination with a microscope. A health care provider performs the biopsy in an outpatient center or a hospital. The patient receives a local anesthetic; however, in some cases, the patient will require general anesthesia.
                
A pathologist examines the skin tissue in a lab and checks the tissue for antibodies that are common in celiac disease. If the skin tissue tests positive for the antibodies, a health care provider will perform blood tests to confirm celiac disease. If the skin biopsy and blood tests both suggest celiac disease, the patient may not need an intestinal biopsy for diagnosis.
                

                
Genetic Tests   In some cases, a health care provider will order genetic blood tests to confirm or rule out a diagnosis of celiac disease. Most people with celiac disease have gene pairs that contain at least one of the human leukocyte antigen (HLA) gene variants.4 However, these variants are also common in people without celiac disease, so their presence alone cannot diagnose celiac disease.   If a biopsy and other blood tests do not give a clear diagnosis of celiac disease, a health care provider may test a patient for HLA gene variants. If the gene variants are not present, celiac disease is unlikely.