Kenneth D. Fine
The New England Journal of Medicine published a study in the May 2, 1996 (Volume 334, Number 18) issue regarding the prevalence of occult gastrointestinal bleeding in patients with celiac sprue. Its goals were to explain the iron deficiency found in many celiacs. The fecal samples of 8 Patients with partial villous atrophy and 28 with total villous atrophy were studied. Their results found 25% of patients with partial villous atrophy and 54% of Patients with total villous atrophy tested positive for blood. They concluded that gastrointestinal bleeding can be found in about 50% of patients with celiac sprue, and should therefore be added to the list of factors that can contribute to iron deficiency in celiacs.
The following are comments on this article by Karoly Horvath, M.D., Ph.D., of Baltimore, Maryland, USA. If you have any questions you can e-mail him at: firstname.lastname@example.org
Date: 05/02/96 - 08:20:20 AM. Subject: Re: Fecal Occult Blood, Plus Elevated Liver Enzymes FECAL OCCULT BLOOD:
The cited NEJM paper found occult intestinal bleeding in patients who had some degree (partial and total) of intestinal villous atrophy. However, this paper have certain methodological problems. The first, and most important -as you can read in the editorial comment- that they did not place the patient on a specific diet before collecting the stool. It is a rule that the patients should be on a diet which eliminate all the peroxidase containing food. So this may increase the number of false positive cases.
The second problem that the hemoccult test is only a screening method, which does not give information about the degree of blood loss. The test can be positive in the presence of small amount of blood in the stool. While this paper has limitations, I should accept that patients with mucosal atrophy and inflammation have small amount of blood loss. So I do not have any doubt regarding the final conclusion of paper, that patients with active celiac disease have blood loss in the stool. This is not surprising and not a novel finding.
To avoid any panic in the celiac community I do not recommend to post this finding without appropriate comment to the Celiac List. We should emphasize one sentence from this paper: ALL THE PATIENTS WITH PREVIOUSLY DIAGNOSED AND TREATED CELIAC SPRUE HAD NEGATIVE TESTS FOR FECAL OCCULT BLOOD.
It is well known that patient with intestinal inflammation may have elevated liver enzymes. The well known examples are patients with inflammatory bowel disease. Because patients with active celiac disease have significant accumulation of inflammatory cells in the mucosa it is not surprising that a percentage of patients with active celiac disease have elevated liver enzymes. However, this is a temporary elevation, which disappears on gluten-free diet.
The explanation is not clear for this finding. The simplified explanation is that there is an increased permeability in the inflamed intestinal segments and different toxins, which normally are detoxified by the enterocyte Cytochrom P450 enzyme system, enter the portal circulation and there is an increased toxin load into the liver.