A biopsy has been considered as one of the gold standards to confirm celiac disease, an autoimmune disease that is caused by gluten, a protein found in wheat, barley, and rye. A biopsy is an invasive procedure, so some do not want to undergo it. In the past 25 years, more tests have been utilized to diagnose celiac disease. Because of this, the criteria to conclusively diagnose a patient were broken down into five:
- The signs and symptoms associated with celiac disease are present.
- Serology screening is positive.
- Predisposing genes are present.
- Evidence in cells and tissues that is typical for those who have celiac disease.
- The serology test becomes normal, and the symptoms were gone after the patient eliminated gluten in their diet.
The utilization of biopsy in diagnosing celiac disease has been a source of debate to many experts. Some of them believe that it is not always a must for this diagnostic test to be conducted, while there are some gastroenterologists that think a biopsy is the best way to go for patients who do not respond well to a diet that is free from gluten. Some of the various researches and studies done to illustrate this controversial topic are listed below.
Studies Questioning the need for Biopsies
Prospective Celiac Disease Diagnostic Evaluation group (ProCeDE)
According to a study that was published in July in Gastroenterology, patients who are 18 years and below can be diagnosed conclusively with the need for them to go through an intestinal if they have at least one symptom, have 10 times higher than normal tissue-transglutaminase (TGA-IgA) result, and have results that are positive from an anti-endomysial test (EMA). The researchers gathered the information for this study for 3 years and from 33 gastroenterology center for children in 21 countries. This study, however, only confirms the need for a biopsy with children and not adults.
Dr. von Hauner Children’s Hospital (Munich, Germany)
In a study that was guided by Dr. von Hauner Children’s Hospital in Munich, Germany, the observation of European Society of Pediatric Gastroenterology, Hepatology and Nutrition guidelines (ESPGHAN) concluded that a biopsy was not needed for a proper diagnosis. The researchers used and applied the same standards. Nevertheless, this particular study did not state if the same results applied to adults.
Dr. Geoffrey Holmes (The Royal Derby Hospital, United Kingdom)
Dr. Holmes, who is a gastroenterologist at The Royal Derby Hospital, co-authored a study that was published in 2016. This study states that celiac disease can be accurately diagnosed with a serology test for adults by utilizing a particular antibody that is IgA-tTG. The others authors supported this conclusion and added it to other pieces of evidence that they have to say that biopsy must not be mandatory. It also resulted in the guidelines for diagnosing celiac disease to be changed, although the British Society of Gastroenterology has not made an official statement about the mandatory biopsy testing for adults.
Dr. Holmes even challenged the experts who support biopsy testing for celiac disease sufferers by asking for other results apart from the high levels of TGA to diagnose. He does not find it acceptable to do a biopsy in this kind of circumstance. However, he also said that there are very important considerations before skipping the biopsy test. The blood test should have a result that indicates damage to the small intestine. This means that the value, which is positive and predictive, must be 100 percent. If a celiac disease sufferer has levels above this, a biopsy is not recommended. The blood test must be conducted by laboratories using a brand that has validation and a high performance level. When the blood test does not meet these criteria, a biopsy must be performed.
Studies that confirm the need for biopsies
For patients who still manifest symptoms of celiac disease even when they have been gluten-free for 6 to 12 months, or for those have blood test results that are positive and have damaged intestines, they are categorized to have an asymptomatic celiac disease. According to studies, 30 percent of patients are included in this group. Some specialists claim that it is 50 percent for those who do not have symptoms but have damaged intestines.
Refractory celiac disease is closely related to asymptomatic celiac disease. Both have an unusual numbers of white blood cells, which are called intraepithelial lymphocytes. These abnormal immune cells are along the small intestine's lining. Determining refractory celiac disease through this can be disturbing since it could be a sign cancer. It is categorized into two kinds: Type I and Type II. Type I affects 1 in 100 patients, and Type II, which is more severe and affects 1 in 200 patients.
These also could be reasons as to why specialists believe that some patients require a biopsy while others do not, especially if they are adults.
Dr. Paul Ciclitira (Rayne Institute, St. Thomas’ Hospital, London)
Dr. Paul Ciclitira, who is a director of the gastroenterology research unit of the Rayne Institute found at St. Thomas’ Hospital in London, stated that he has treated around 100 patients with Type II refractory celiac disease. According to him, if this condition goes unnoticed, there is a 50 percent chance that the patient will die. Without the proper diagnosis with an endoscopy and biopsy, he said that the mortality rate from celiac disease will increase.
If a biopsy is not done, an incorrect diagnosis might happen. This occurs in 9 percent of all the patients who have blood test results that came out as negative. A misdiagnosis can also happen for a positive tTG tests for those who have thyroid-related diseases and diabetes.
Dr. Abdul Al-Toma (St. Antonius Hospital, the Netherlands)
Dr. Al-Toma, who is a gastroenterologist at St. Antonius Hospital in the Netherlands, thinks that a biopsy is the confirmatory test for celiac disease. He said that it is very important to have this test for patients with a non-responsive celiac disease as the results taken for diagnostic purposes and for the follow-up can be compared. This would also correctly assess the patient's recovery.
Moreover, he stated that a biopsy can detect how severe the damage is to the villi that are located in the intestine. From this, potential complications such as osteoporosis can occur. Based on experience, he added that patients who did not have a biopsy tend to not follow a strict gluten-free diet. According to him, a thorough discussion regarding this matter is indeed needed before making big changes in the approach of detecting celiac disease.
North American Society of Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN)
The North American Society of Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) does not disregard biopsy as a diagnostic test for celiac disease. They still order for a biopsy for all their young patients. This organization does not want to depend completely on EMA test. Although it is reliable for diagnosis, they think that misinterpretations will most likely occur which can cost more for the patients. EMA test can be used if tTG blood test is positive but the opposite for biopsy.
Though this debate is still ongoing, it is safe to say that in some situations a biopsy is still needed. Patients who only exhibit a few symptoms or asymptomatic, and those who have an abnormal rise in the number of celiac antibodies or deficiency in predisposing genes are candidates for a biopsy.
But, because of the variety of opinions and different factors, they should not be held as high as a standard as they are by many hospitals worldwide.