NEW YORK — Capsule endoscopy, a promising alternative to upper endoscopy for the investigation and diagnosis of celiac disease, may one day negate the need for endoscopically obtained intestinal biopsies, Dr. Ernest Seidman said at an international conference on celiac disease.
“I don't think that we can yet say that the capsule should replace the biopsy in every case,” said Dr. Seidman, professor of medicine and pediatrics at McGill University, Montreal, and also a consultant for Given Imaging, which makes the only FDA-approved capsule endoscope. “The consensus opinion is that capsule endoscopy is equivalent to histology [for celiac disease], but only in those with severe villous atrophy. More data is required to prove diagnostic equivalence for those with partial atrophy.”
Usually, patients with serologic evidence of celiac disease undergo intestinal biopsy to verify the presence of villous atrophy, which is currently the definitive diagnostic finding. But a consensus of expert opinion from the International Conference on Capsule Endoscopy in Paris last June suggested that the tool may be an alternative for patients who are unwilling or unable to undergo biopsy, for those whose initial biopsy is equivocal, and for patients with confirmed celiac disease who develop alarming symptoms despite adherence to a gluten-free diet (Endoscopy 2005;37:1055–9).
One advantage of capsule endoscopy in the investigation of celiac disease is that it offers unprecedented views of the small bowel in its entirety.
“So much of the small bowel has been a black box for us, and with capsule endoscopy, we can see areas that are not accessible with the upper endoscope,” Dr. Seidman said.
Capsule endoscopy is also state-of-the-art technology for examining the intestinal lining for other small bowel disorders. “We can see target lesions that would not otherwise be detectable by other imaging methods. Moreover, villous appearance can be seen extremely well—the resolution of the camera is extraordinary. We see villi routinely without doing magnification, and when the villi are atrophic or edematous, it's very apparent,” he added.
Capsule findings of the intestinal lining that are suggestive of celiac disease include fissuring, scalloping, a mosaic pattern, nodularity, and delayed appearance of villi with a loss of circular folds, he said.
Although the avoidance of endoscopy and sedation may be particularly attractive when dealing with pediatric patients, children under the age of 8 years are rarely able to swallow the jelly bean-size capsule, he said, adding that getting them to demonstrate with a real jelly bean is a wise idea.
“Otherwise, you run into a situation where you have opened the blister pack, which activates the camera, and you have the child holding it and saying they can't do it. It's an expensive way to get pictures of their face,” he said.
There is a delivery device that allows the introduction of the capsule into the small bowel with an endoscope, but this negates much of the advantage of the capsule, he said.
Even after starting a gluten-free diet, patients with celiac disease might face up to a 40-fold increased risk of developing small bowel lymphomas, compared with people who do not have celiac disease.
Consequently, recurrent or persistent bowel symptoms in diagnosed patients following a strict gluten-free diet are to be carefully evaluated and investigated. Capsule endoscopy often reveals abnormalities in such patients, Dr. Seidman said.
“Small bowel tumors are notoriously silent until it's too late—and finding them is extremely difficult. Needless to say, capsule endoscopy is the most proficient way to look for these tumors,” he said.
A recent study of capsule endoscopy in 47 celiac patients with abdominal pain or other symptoms suggestive of malignancy found cancer in 5%, ulcerations in 50%, and villous atrophy in 68% (indicating noncompliance with the gluten-free diet), he said (Gastrointest. Endosc. 2005;62:55–61).