Coeliac Patients In Remission Research Articles

HMGB1 is related to disease activity in children with celiac disease

IntroductionWe aim to evaluate of the relationship between high mobility gene box-1 (HMGB1) levels and clinical, laboratory and histopathological findings at diagnosis and in remission in children with Celiac Disease (CD). Material and MethodsThe study included 36 celiac patients at diagnosis, 36 celiac patients in remission, and 36 healthy controls. Patients with intestinal pathologies other than CD, and accompanying inflammatory and/or autoimmune diseases were excluded. Relationship between HMGB1 levels and clinical, laboratory and histopathological findings were evaluated. ResultsA total of 72 celiac patients [36 (18 girls, 18 boys, mean age 9.41±3.9 years) in group 1 and 36 (18 girls, 18 boys, mean age 9.91±3.36 years) in group 2] and 36 healthy controls in group 3 (19 girls, 17 boys, mean age 9.56±4 years) were included. The HMGB1 level was significantly higher in group 1 compared to group 2 and group 3 [36.63 (17.98–54.72) ng/ml vs 20.31 (16.89–29.79) ng/ml, p = 0.028 and 36.63 (17.98–54.72) ng/ml vs 20.38 (17.54–24.53) ng/ml p = 0.012, respectively]. A serum HMGB-1 level of 26.553 ng/ml was found to be a cut-off value for the CD with 61% sensitivity, 83% specificity, 78% positive predictive value, and 68% negative predictive value. Higher HMGB1 values were seen in patients with intestinal findings, anemia, anti-tissue transglutaminase IgA levels that were greater than 10 times upper limit of normal, and patients with a higher degree of atrophy as classified by Marsh-Oberhuber. ConclusionsIn conclusion, it was thought that HMGB-1 might be a marker that reflects the severity of atrophy at the time of diagnosis and could be used to control dietary compliance in the follow-up. However, there is need for larger population studies in order to evaluate its value as a serological marker for the diagnosis and follow-up of CD and to find a more reliable cut-off value.

The Pros and Cons of Using Oat in a Gluten-Free Diet for Celiac Patients.

A therapeutic gluten-free diet often has nutritional limitations. Nutritional qualities such as high protein content, the presence of biologically active and beneficial substances (fiber, beta-glucans, polyunsaturated fatty acids, essential amino acids, antioxidants, vitamins, and minerals), and tolerance by the majority of celiac patients make oat popular for use in gluten-free diet. The health risk of long-time consumption of oat by celiac patients is a matter of debate. The introduction of oat into the diet is only recommended for celiac patients in remission. Furthermore, not every variety of oat is also appropriate for a gluten-free diet. The risk of sensitization and an adverse immunologically mediated reaction is a real threat in some celiac patients. Several unsolved issues still exist which include the following: (1) determination of the susceptibility markers for the subgroup of celiac patients who are at risk because they do not tolerate dietary oat, (2) identification of suitable varieties of oat and estimating the safe dose of oat for the diet, and (3) optimization of methods for detecting the gliadin contamination in raw oat used in a gluten-free diet.

Effect of Gliadin on Permeability of Intestinal Biopsy Explants from Celiac Disease Patients and Patients with Non-Celiac Gluten Sensitivity

Background: Intestinal exposure to gliadin leads to zonulin upregulation and consequent disassembly of intercellular tight junctions and increased intestinal permeability. We aimed to study response to gliadin exposure, in terms of barrier function and cytokine secretion, using intestinal biopsies obtained from four groups: celiac patients with active disease (ACD), celiac patients in remission (RCD), non-celiac patients with gluten sensitivity (GS) and non-celiac controls (NC). Methods: Ex-vivo human duodenal biopsies were mounted in microsnapwells and luminally incubated with either gliadin or media alone. Changes in transepithelial electrical resistance were monitored over 120 min. Media was subsequently collected and cytokines quantified. Results: Intestinal explants from all groups (ACD (n = 6), RCD (n = 6), GS (n = 6), and NC (n = 5)) demonstrated a greater increase in permeability when exposed to gliadin vs. media alone. The increase in permeability in the ACD group was greater than in the RCD and NC groups. There was a greater increase in permeability in the GS group compared to the RCD group. There was no difference in permeability between the ACD and GS groups, between the RCD and NC groups, or between the NC and GS groups. IL-10 was significantly greater in the media of the NC group compared to the RCD and GS groups. Conclusions: Increased intestinal permeability after gliadin exposure occurs in all individuals. Following gliadin exposure, both patients with gluten sensitivity and those with active celiac disease demonstrate a greater increase in intestinal permeability than celiacs in disease remission. A higher concentration of IL-10 was measured in the media exposed to control explants compared to celiac disease in remission or gluten sensitivity.

Short wheat challenge is a reproducible in-vivo assay to detect immune response to gluten

It has been reported that interferon (IFN)-γ-secreting T cells reactive to gluten can be detected in the peripheral blood of individuals with treated coeliac disease (CD) after a short consumption of wheat-containing food. By contrast, very little is known about the reproducibility of this in-vivo procedure in the same patient cohort which underwent two, or more, gluten consumptions. Fourteen coeliac patients in remission consumed wheat bread for 3 days; 13 underwent a second gluten challenge after a wash-out of 3-10 months on a strict gluten-free diet. Immune reactivity to gluten was analysed in peripheral blood by detecting IFN-γ before and 6 days after commencing a gluten diet. Gliadin-specific IFN-γ-secreting CD4(+) T cells increased significantly on day 6 of the first challenge. These cells resulted as prevalently human leucocyte antigen (HLA)-DQ restricted and with a phenotype of gut homing, as suggested by the expression of β7-integrin. Similarly, reactiveness to gliadin was observed after the second wheat consumption, although with an individual variability of responses at each challenge. Our findings confirmed that the short wheat challenge is a non-invasive approach to investigate the gluten-related immune response in peripheral blood of subjects intolerant to gluten. Furthermore, we demonstrated that the in-vivo procedure can be reproduced in the same subject cohort after a gluten wash-out of at least 3 months. Our study has important implications for the application of this procedure to clinical practice.

Nutrient intakes during diets including unkilned and large amounts of oats in celiac disease

We have shown earlier that consumption of moderate amount of oats improve intakes of vitamin B(1), fiber, magnesium and iron in celiac patients using gluten-free diet (GFD). The objective of this study was to clarify the effect of high amount of both kilned and unkilned oats on food and nutrient intakes in celiac patients in remission. Kilning as an industrial heating process is performed to preserve the main properties of oats and to lengthen its useableness. Kilning may, however, change the protein structure of oats and therefore influence on the intake of nutrients. The study group consisted of 13 men and 18 women with celiac disease in remission. The patients who were earlier using moderate amount of oats as part of their GFD were randomized to consume kilned or unkilned oats. After 6 months, the patients changed the treatment groups. The goal of daily intake of oats was 100 g. Food records and frequency questionnaire were used to follow nutrient intakes. Type of oats did not affect the amount of oats used. In the group using kilned oats, the intake of vitamin B1 and magnesium and in the group of unkilned oats that of magnesium and zinc increased significantly during the first 6 months (P<or=0.05). :Large amounts of oats, both kilned and unkilned in GFD, can increase intakes of nutrients in celiac patients in remission. Oats improve the nutritional value of GFD.

Effect of unkilned and large amounts of oats on nutritional state of celiac patients in remission

Summary Background Moderate amounts of oats have not had any harmful effect on the nutritional state of celiac patients. Common technical processing, e.g. kilning of oats, may affect its protein structures and therefore may increase its tolerability in patients and further influence their nutritional state. Aims To investigate the effect of large amounts of regular kilned or unkilned oats on the nutritional status of celiac patients in remission. Methods The patients (13 men and 18 women) who were previously using regular kilned oats as part of a gluten free diet were randomized to consume large amounts of either kilned or unkilned oats. After 6 months the patients changed the treatment groups. The goal of the daily intake of oats was 100 g. Anthropometric measurements, food records and laboratory test were used to investigate the nutritional status. Results The groups did not differ from each other in nutritional status. During the oat diets, at first temporarily, the values of serum calcium, magnesium and vitamin B 12 slightly decreased but stayed within the normal limits for the 12 months of the follow-up. Conclusions Unkilned or kilned oats, even in large amounts produced no harm to the nutritional status of celiac patients during over a 1-year period.

Gliadin, zonulin and gut permeability: Effects on celiac and non-celiac intestinal mucosa and intestinal cell lines

Objective. Little is known about the interaction of gliadin with intestinal epithelial cells and the mechanism(s) through which gliadin crosses the intestinal epithelial barrier. We investigated whether gliadin has any immediate effect on zonulin release and signaling. Material and methods. Both ex vivo human small intestines and intestinal cell monolayers were exposed to gliadin, and zonulin release and changes in paracellular permeability were monitored in the presence and absence of zonulin antagonism. Zonulin binding, cytoskeletal rearrangement, and zonula occludens-1 (ZO-1) redistribution were evaluated by immunofluorescence microscopy. Tight junction occludin and ZO-1 gene expression was evaluated by real-time polymerase chain reaction (PCR). Results. When exposed to gliadin, zonulin receptor-positive IEC6 and Caco2 cells released zonulin in the cell medium with subsequent zonulin binding to the cell surface, rearrangement of the cell cytoskeleton, loss of occludin-ZO1 protein–protein interaction, and increased monolayer permeability. Pretreatment with the zonulin antagonist FZI/0 blocked these changes without affecting zonulin release. When exposed to luminal gliadin, intestinal biopsies from celiac patients in remission expressed a sustained luminal zonulin release and increase in intestinal permeability that was blocked by FZI/0 pretreatment. Conversely, biopsies from non-celiac patients demonstrated a limited, transient zonulin release which was paralleled by an increase in intestinal permeability that never reached the level of permeability seen in celiac disease (CD) tissues. Chronic gliadin exposure caused down-regulation of both ZO-1 and occludin gene expression. Conclusions. Based on our results, we concluded that gliadin activates zonulin signaling irrespective of the genetic expression of autoimmunity, leading to increased intestinal permeability to macromolecules.

EARLY EFFECTS OF GLIADIN ON HUMAN INTESTINAL MUCOSA AND INTESTINAL CELL LINES

Background & Aims: The mechanism(s) of interaction of gliadin with intestinal epithelial cells are still largely unknown. Based on our recent discovery of zonulin, a modulator of intestinal tight junctions, and its up-regulation in celiac disease, we elected to establish whether gliadin has any immediate effect on the zonulin pathway. Methods: Both ex vivo human small intestines and intestinal cell monolayers were exposed to gliadin, and zonulin release and changes in paracellular permeability were monitored in the presence and absence of zonulin antagonism. Zonulin binding, cytoskeletal rearrangement, and zonula occludens-1 re-distribution were evaluated by immunofluorescence microscopy. Results: Zonulin receptor positive IEC6 and Caco 2 cells exposed to gliadin released zonulin with subsequent zonulin binding to the cell surface, rearrangement of the cell cytoskeleton, loss of occludin-ZO1 protein-protein interaction, and increased monolayer permeability. Pretreatment with the zonulin antagonist FZI/0 blocked these changes. When exposed to luminal gliadin, intestinal biopsies from celiac patients in remission expressed a sustained luminal zonulin release and increase in intestinal permeability that was blocked by FZI/0 pre-treatment. Conversely, biopsies from non-celiac patients demonstrated a limited, transient zonulin release which was paralleled by a reduction in intestinal TEER that never reached the level of permeability seen in CD tissues. Chronic gliadin exposure caused a down-regulation of both ZO-1 and occludin gene expression. Conclusions: Gliadin activates the zonulin system irrespective of the genetic predisposition to autoimmunity, leading to increased intestinal permeability to macromolecules.

Enzyme therapy for management of coeliac disease

Objective. Enzyme therapy based on animal digestive extracts was investigated as a means of completely digesting toxic residues from gluten in the small intestine, thus providing a means of protection of the mucosa. Material and methods. A randomized, placebo-controlled, clinical trial of an encapsulated enzyme extract was conducted in 21 coeliac patients in remission who were challenged with a modest amount of gluten daily over 2 weeks. Enzyme extract (900 mg) in three divided doses was administered during this challenge to half the group and a placebo to the other half in a double-blind, crossover design. Symptoms were recorded in daily diaries; blood was taken for tissue transglutaminase antibodies (anti-tTG) at the start and at intervals up to 12 weeks. Duodenal biopsies were performed for histological assessment at the start and end of each challenge period for 6 patients chosen at random from volunteers. After a further 10 weeks, the groups were changed over, and the same assessments carried out. Results. Only 8 of the 21 patients (38%) had more than 5 episodes of moderate to severe symptoms during either of the gluten challenge periods, and in these, symptoms scores were ameliorated during enzyme therapy compared with the placebo period (p<0.02). Rises of 5 U/ml or more in anti-tTG occurred in only 5 patients at about 6–8 weeks after challenge, but were not correlated with symptoms. Conclusions. Only 1 of the 6 patients had normal histology at entry, thus focusing attention on the need for better management of the disease. By histological criteria, enzyme therapy offered better protection than placebo during the gluten challenges. The study supports the use of enzyme supplementation as a safeguard for patients with coeliac disease because of the difficulty of ensuring a strictly gluten-free diet.

Adult coeliac patients do tolerate large amounts of oats.

The aim of the present study was to investigate whether adult patients with coeliac disease in remission could include large amounts of oats in their daily gluten-free diet for an extended period of time without adverse effects. Twenty adult coeliac patients in remission included large amounts of uncontaminated rolled oats in their daily diet for a prolonged period. The examinations, performed four times during the study period, included small bowel endoscopy with biopsies, blood samples (nutritional status, serological analysis), height and body weight, gastrointestinal symptoms and dietary records. Gastrointestinal symptoms and diet were also investigated through unannounced telephone interviews once a month during the study period. No adverse effects of a large intake of oats were seen in small bowel histology, serology nor in nutritional status in the 15 subjects who completed the whole study period. Two of the subjects dropped out because of gastrointestinal symptoms and three for non-medical reasons. The median intake of oats was 93 g/day and the compliance to the oat diet was found to be good. Examinations of the patients after drop-out did not show any deterioration in small bowel histology or nutritional status nor raised levels of antibodies. Results from this study indicate that adult patients with coeliac disease in remission can include large amounts of controlled wheat-free rolled oats for an extended period of time without adverse effects.

THE IN VITRO-INFLUENCE OF GLIADIN PEPTIDES ON THE HYDROLASES OF THE DUODENAL BRUSH BORDER MEMBRANE IN COELIAC DISEASE IN REMISSION

Aims: The molecular mechanism inducing the mucosal damage in coeliac disease (CD) is still unknown. Gliadin causes villus atrophy in CD, and patients on a gluten-free diet recover completely. On the basis of the organ culture of intestinal biopsies we developed an in vitro-system for CD in remission. We used this model to verify our hypothesis postulating a correlation between the mucosal damage caused by gliadin and the biosynthesis of the intestinal hydrolases. Besides we measured the enzyme activity to prove whether this level is afflicted additionally or alternatively. Methods: Intestinal biopsies from 14 coeliac patients in remission (following a gluten-free diet for at least 2 years) and 23 healthy children (control group) were organ cultured for 24 hours in presence or absence of gliadin peptides. A peptictryptic digest of maize prolamine operated as the non-toxic control. The effect of these additives on the enzyme activity of the disaccharidases was determined by a modificated method of Dahlqvist. The influence on the biosynthesis of several hydrolases (LPH, SI, MGA, ACE, APN, DPP IV) was studied by biosynthetical protein-labelling during organ culture, followed by immunoprecipitation, SDS-PAGE, autoradiography and quantified by densitometric scanning. Results: In our model we demonstrated a rapid and specific gliadin-induced reduction of the biosynthesis of all studied hydrolases in biopsies from coeliac patients on gluten-free diet. This phenomenon was neither seen after incubation with maize prolamine nor in healthy children. We could not show an effect of gliadin on the disaccharidase activities after 24 hours of incubation. Because of beginning necrosis in the biopsies a longer incubation was not possible, so we were not able to examine later effects. Conclusions: Our model is suitable for studying the in vitro-situation of CD in remission. Moreover, our results indicate a fast effect of gliadin peptides on inhibiting the biosynthesis of hydrolases of duodenal brush border membranes. It remains unclear whether the gliadin-induced reduction primarily influences the protein biosynthesis or has to be interpreted as a secondary effect of an impaired mRNA synthesis. We suppose that the effect occurs at the translational or transcriptional level. The early modifications within 24 hours of incubation are hardly to explain by activities of the immune system. More likely the results suggest a toxic effect of gliadin peptides on the intestinal mucosa preceeding immunological changes mediated by cytokines.

Cytokine mRNA expression in the mucosa of treated coeliac patients after wheat peptide challenge.

This study investigated the presence of mRNA coding for interferon gamma (IFN gamma), tumour necrosis factor alpha (TNF alpha), and interleukins 2 (IL2) and 6 (IL6), in the mucosa of four coeliac patients in remission who had been challenged with either gliadin or synthetic gliadin oligopeptides. Jejunal biopsy specimens from these patients, taken before and at two, four, and six hours after challenge, were hybridised with specific 35S-labelled DNA oligonucleotide probes. The lamina propria of all the patients contained significantly increased numbers of cytokine mRNA expressing cells four hours after challenge with gliadin or an oligopeptide corresponding to amino acids 31-49 of A-gliadin (peptide A). No significant changes were seen with the peptides corresponding to aminoacids 202-220 (peptide B) or 3-21 (peptide C) of A-gliadin, with the exception of one patient who showed a significant increase in the number of TNF alpha mRNA expressing cells four hours after challenge with peptide B. In vivo studies in coeliac disease have shown that significant histological changes occur in the mucosa of treated coeliac patients four hours after challenge with either gliadin or peptide A. These findings suggest that the histological changes seen previously in the mucosa of coeliac patients after wheat peptide challenge may be caused by increased expression of cytokines within the mucosa.

Intakes of nutrients and nutritional status in coeliac patients.

The intake of nutrients and the nutritional status of untreated coeliac patients and coeliac patients in remission were investigated at Kuopio University Hospital. Forty untreated and 52 coeliac patients in remission were admitted to the study. The control group included 77 persons. Four-day food records, anthropometric measurements, and blood biochemistry were examined to obtain nutrient intake and nutritional status. Concentrations of serum ferritin, vitamin B12, and erythrocyte folate were lower in patients with untreated coeliac disease than in those in remission. Altogether, 15-38% of the untreated patients but only 0-20% of the patients in remission had levels of haemoglobin, serum ferritin, iron, vitamin B12, or erythrocyte folate below the reference values. No difference in anthropometric measurements was found between the two groups of coeliac patients. Except for some subclinical abnormal values in biochemical analyses in 20-38% of coeliac patients, nutritional status was quite normal in both groups of coeliac patients.

The Intestinal Mucosa of Coeliacs in Remission is Unable to Abolish the Agglutinating Activity of Gliadin Peptides on K562(S) Cells

The peptic-tryptic-cotazym digest of a wheat gliadin was fractionated into ten primary fractions. Subfraction 2R of fraction 9 is known to be toxic to patients with coeliac disease. Fraction 9 and subfraction 2R also agglutinate K562(S) cells, previously shown to be a good indication of toxicity to in vitro intestinal bioptic specimens from coeliac patients. Subfraction 2R was still able to agglutinate K562(S) cells after digestion by morphologically normal small intestinal mucosa of coeliacs in remission, but was inactivated after digestion by normal mucosa. These results are consistent with the hypothesis that there is a mucosal defect in handling gliadin peptides in coeliac patients, and suggest that there is either a primary (or secondary) enzyme deficiency, or some other mechanism, operating in the intestinal mucosa of coeliac patients in remission.

Intestinal mucosa of celiacs in remission is unable to abolish toxicity of gliadin peptides on in vitro developing fetal rat intestine and cultured atrophic celiac mucosa.

Subfraction 2R of fraction 9 from a peptic-tryptic-pancreatic digest of wheat gliadin is known to be toxic in vivo to celiac patients. We have found that fractions 9 and 2R inhibit the in vitro development of fetal rat intestine and the increase of enterocyte height occurring in organ culture of atrophic celiac mucosa (0.1-0.5 mg/ml medium). Other peptide fractions of the gliadin digest are devoid of such in vitro effects. Subfraction 2R, after incubation with morphologically normal small intestinal mucosa of celiacs in remission and ultrafiltration, was still very active in both culture systems at low concentration (0.1 mg/ml); on the contrary, subfraction 2R was inactivated after incubation with normal mucosa. These results are compatible with the hypothesis that there is a mucosal defect in handling gliadin peptides in celiac disease, and suggest that there is either a primary (or secondary) enzyme deficiency or some other mechanism operating in the intestinal mucosa of celiac patients in remission.

In vitro activation of adenylate cyclase of atrophic celiac intestinal mucosa by wheat gliadin-derived peptides.

In order to demonstrate that gliadin peptides may interact with cell membranes of celiac small intestinal mucosa, the capacity of these peptides to activate the cell membrane enzyme adenylate cyclase was tested. The addition of peptides from bread wheat purified A-gliadin and whole gliadin (proteins that are toxic for celiac patients) enhanced the adenylate cyclase activity of crude cell membrane preparations obtained from atrophic small intestinal mucosa of celiac patients. No activation of adenylate cyclase of this tissue was observed with peptides from proteins nontoxic for celiac patients (bread wheat albumin and maize prolamin). Gliadin peptides did not activate adenylate cyclase of morphologically normal small intestinal mucosa from normal subjects or from celiac patients in remission. These results, therefore, suggest that peptides from bread wheat gliadin may interact with cell membrane of atrophic small intestinal mucosa of celiac patients.

T-lymphocyte activation by a gluten fraction, glyc-gli. Studies of adult coeliac patients and healthy controls.

A gluten fraction (glyc-gli) induced proliferation of T lymphocytes obtained from coeliac patients or healthy controls. Glyc-gli acted as an antigen, and T-cell activation was strongly dependent on antigen-presenting monocytes in the cultures. The lymphocyte response was similar for HLA-B8/DR3-positive and HLA-B8/DR3-negative healthy controls, and coeliac patients in remission on a gluten-free diet could not be distinguished from the controls by the degree of proliferative activity in this test. Conversely, untreated coeliac patients showed a significantly lower lymphocyte response to glyc-gli than both coeliac patients in remission and controls. This result may reflect sequestration of gluten-specific cells into the mucosal lesion or mesenteric lymph nodes in patients with active coeliac disease.

Further evidence of a primary mucosal defect in coeliac disease.

Subfractions of fraction 9, obtained from a peptic-tryptic-pancreatinic digest of wheat gliadin, were subjected to in vitro mucosal digestion and the filtrates examined for residual peptides. Small-intestinal mucosa from four groups of individuals were studied-eight patients with coeliac disease in remission; eight healthy controls; nine first degree relatives of patients with coeliac disease, and six children with recurrent diarrhoea investigated for possible coeliac disease, but in whom the diagnosis was excluded. The highest amounts of residual peptides (measured by scanning densitometer) were detected after digestion with mucosa from patients with coeliac disease and the lowest amounts with the control groups. The results obtained with the group of relatives fell between those of the coeliac disease and control groups, while the recurrent diarrhoea group overlapped the relatives and controls. The residual peptides were derived chiefly from the B-type subfractions of subfractions 1 and 2, obtained by ion-exchange chromatography of fraction 9. These subfractions are rich in glutamine/glutamic acid and proline and have a molecular weight (apparent) of not greater than 1500 Daltons. The results lend further support to the hypothesis of an enzyme deficiency in coeliac disease. A partial enzyme deficiency may exist in some first-degree relatives and in some children with recurrent diarrhoea but with histology of the small intestine within normal limits. HLA-B8 antigen is not correlated with this deficiency, but, when the two factors are associated, they could be related to the manifestation and severity of coeliac disease.

Coeliac disease: the abolition of gliadin toxicity by enzymes from Aspergillus niger.

1. Gliadin from which carbohydrate was removed by treatment with carbohydrase from Aspergillus niger was fed to three coeliac patients in remission. 2. Xylose absorption, mucosal morphology and brush-border enzymes were used to assess the toxicity of the carbohydrase-treated gliadin. 3. Gliadin treated with carbohydrases did not damage the intestinal mucosa of the coeliac patients. 4. The primary structure of the gliadin proteins was not altered by the enzyme treatment.

The Distribution and Enteric Loss of &lt;sup&gt;51&lt;/sup&gt;Cr-Labelled Lymphocytes in Normal Subjects and in Patients with Coeliac Disease and Other Disorders of the Small Intestine

Peripherally harvested lymphocytes have been labelled with 51Cr, reinjected into human subjects and their distribution then studied. Evidence is presented which suggests faecal loss of 51Cr represents loss of T lymphocytes and that there is normally a pathway of lymphocyte removal into the gut of probable importance in lymphocyte migration streams. In 9 normal subjects, without structural intestinal disease, faecal loss of lymphocytes over 5 days was 0.20% (SEM +/- 0.06) whereas in 5 patients with untreated coeliac disease faecal loss was 1.13 +/- 0.34%, in 7 with Crohn's disease it was 1.01 +/- 0.21% and in 5 with intestinal lymphangiectasia loss was 0.61 +/- 0.10%. In 1 patient with acute tropical sprue, enteric loss was 0.97%. By contrast, faecal loss was normal in 3 coeliac patients in remission on a gluten-free diet. Measurements were also made using an external counter. In contrast to the normals, where count rates steadily diminished, an increasing activity was recorded over the umbilicus over 7 days after dose administration in all the disease categories studied with the exception of the treated coeliacs. The finding of an increased enteric loss of lymphocytes may explain many of the immunological abnormalities in the conditions studied.