Small-bowel mucosal transglutaminase 2-specific IgA deposits in coeliac disease without villous atrophy: A prospective and randomized clinical study

Objective In coeliac disease, autoantibodies directed against transglutaminase 2 are produced in small-bowel mucosa, and they have been found to be deposited extracellularly. The aim of this study was to investigate whether such mucosal IgA deposits are important in the diagnostic work-up of early-stage coeliac disease without small-bowel mucosal villous atrophy.

Material and methods Forty-one adults suspected of coeliac disease owing to increased density of mucosal γδ+ intraepithelial lymphocytes but normal villous morphology were randomized to gluten challenge or a gluten-free diet for 6 months. Clinically and histologically verified gluten dependency was compared with existence of small-bowel mucosal transglutaminase 2-specific extracellular IgA deposits and (coeliac disease-type) HLA DQ2 and DQ8; 34 non-coeliac subjects and 18 patients with classical coeliac disease served as controls.

Results Of the 41 patients, 5 in the challenge group and 6 in the gluten-free diet group were clinically gluten sensitive; all 11 had HLA DQ2 or DQ8. Ten of these 11 patients showed transglutaminase 2-targeted mucosal IgA deposits, which were dependent on gluten consumption. Minimal IgA deposits were seen in only 3 out of 30 patients with suspected coeliac disease without any clinically detected gluten dependency. The deposits were found in all classical coeliac patients and in none of the non-coeliac control subjects.

Conclusions Clinically pertinent coeliac disease exists despite normal small-bowel mucosal villous architecture. Mucosal transglutaminase 2-specific IgA deposits can be utilized in detecting such patients with genetic gluten intolerance.     

Endomysial antibody-negative coeliac disease: clinical characteristics and intestinal autoantibody deposits

BACKGROUND: Some patients with untreated coeliac disease are negative for serum endomysial autoantibodies (EmA) targeted against transglutaminase 2 (TG2). AIMS: To evaluate the clinical and histological features of EmA-negative coeliac disease, and to examine whether EmA-equivalent autoantibodies against TG2 can be seen in the small-bowel mucosa when absent in serum. PATIENTS: Serum EmA was studied in 177 biopsy-proved specimens from adult patients with coeliac disease. 20 patients with intestinal diseases served as non-coeliac controls; three had autoimmune enteropathy with villous atrophy. METHODS: Clinical manifestations, small-bowel mucosal morphology, intraepithelial inflammation and TG2-specific extracellular immunoglobulin A (IgA) deposits were investigated in both serum EmA-negative and EmA-positive patients. RESULTS: 22 patients with IgA-competent coeliac disease were negative for serum EmA. Three of these had small-bowel lymphoma. Patients with EmA-negative coeliac disease were older, had abdominal symptoms more often, and the density of gammadelta+ intraepithelial lymphocytes in their intestinal mucosa was lower than in EmA-positive patients; otherwise the histology was similar. All serum EmA-negative patients with coeliac disease, but none of the disease controls, had gluten-dependent mucosal IgA deposits alongside TG2 in the small-bowel mucosal specimens. In vivo deposited IgA was shown to be TG2-specific by its ability to bind recombinant TG2. CONCLUSIONS: Negative serum EmA might be associated with advanced coeliac disease. TG2-targeted autoantibodies were deposited in the small-bowel mucosa even when absent in serum. This finding can be used in the diagnosis of seronegative coeliac disease when the histology is equivocal. It may also be helpful in the differential diagnosis between autoimmune enteropathy and coeliac disease.     

Altered small-bowel mucosal vascular network in untreated coeliac disease

Objective. It has recently been shown that serum autoantibodies targeted against transglutaminase 2 derived from untreated coeliac patients can disturb several steps of angiogenesis in vitro. The purpose of this study was to establish whether the small-bowel mucosal vasculature is altered in coeliac disease and whether the putative changes are gluten dependent. Material and methods. The small-bowel mucosal microvessel architecture was examined in duodenal biopsy samples from coeliac patients before and after a gluten-free diet and from non-coeliac controls. In addition, the vasculature was subjected to a detailed morphometric analysis. Double immunofluorescent stainings of the vasculature with anti- α-smooth muscle actin antibody were performed in order to assess the maturity of mucosal vessels. Coeliac disease-specific transglutaminase 2-targeted autoantibody deposits in the vessel wall were studied using triple immunofluorescent stainings. Results. On a gluten-containing diet the mucosal vasculature in the small intestine of untreated coeliac disease patients was altered in overall organization as well as in the number and maturity of the vessels when compared to healthy subjects. In patients on a gluten-free diet, the vasculature normalized parallel to mucosal recovery. Conclusions. In coeliac disease, ingestion of gluten leads to altered appearance of small-bowel mucosal microvasculature. It is thus conceivable that the small-bowel mucosal vascular biology might be involved in the pathogenesis of coeliac disease.     

Intraepithelial lymphocytes and coeliac disease

The diagnosis of coeliac disease is easy in cases with symptoms and unequivocal small intestinal villous atrophy. However, patients often suffer from only subtle if any symptoms. Borderline villous shortening is common, making the histologic diagnosis difficult. The increase in intraepithelial lymphocytes is typical even in early-stage untreated coeliac disease. Unfortunately, this finding is unspecific. In coeliac disease, the relative density of gammadelta+ intraepithelial lymphocytes is increased. The presence of IgA class anti-endomysium or anti-tissue transglutaminase antibodies clearly increases the likelihood of the disease. Coeliac disease is closely linked to HLA DQ2 and DQ8, and their absence speaks strongly against the condition, whereas a positive finding is virtually of no diagnostic value. In borderline cases, the gluten-dependency of symptoms or mucosal inflammation should be shown by gluten-free diet or gluten challenge. No single test is efficient enough to distinguish unspecific increase in intraepithelial lymphocytes from early coeliac disease; clinical history, histology, serology and gluten-dependency should be taken into account in the diagnostic work-up.     

Resurrection of gliadin antibodies in coeliac disease. Deamidated gliadin peptide antibody test provides additional diagnostic benefit

OBJECTIVE: Circulating antibodies against naive, whole gliadin have been replaced by more accurate endomysial and tissue transglutaminase antibody tests in the diagnosis of coeliac disease. The purpose of this study was to compare these serological tests with a new test recognizing antibodies against deamidated and defined gliadin peptides. MATERIAL AND METHODS: The study population comprised selected coeliac disease patients in a tertiary clinic: newly detected patients before and after a gluten-free diet, patients with persistent small-bowel mucosal villous atrophy despite a strict gluten-free diet and non-coeliac controls reporting abdominal symptoms after ingestion of cereals. Comparisons were made between serum IgA-class gliadin peptide, endomysial, tissue transglutaminase and conventional gliadin antibodies. RESULTS: The deamidated gliadin peptide antibody test showed a sensitivity of 91% and a specificity of 98% in coeliac disease. The tissue transglutaminase antibody test performed equally well. The specificity of endomysial antibody was just as high, but its sensitivity was lower, 80%. The conventional gliadin antibody test showed poor sensitivity and specificity. Combination of the deamidated gliadin peptide and tissue transglutaminase tests offered the best sensitivity without loss of specificity in the diagnosis of coeliac disease. All antibody levels declined in line with mucosal recovery. The deamidated gliadin peptide antibody test showed six of the nine cases with small-bowel mucosal damage persisting on a gluten-free diet, whereas tissue transglutaminase detected only two cases and endomysial antibody none. CONCLUSIONS: The new gliadin peptide antibody test proved highly accurate in the diagnostic work-up and follow-up of coeliac disease and can be endorsed in combination with the tissue transglutaminase test.     

Wheat starch-containing gluten-free flour products in the treatment of coeliac disease and dermatitis herpetiformis. A long-term follow-up study

BACKGROUND: We investigated whether wheat starch-based gluten-free products are safe in the treatment of gluten intolerance. METHODS: The study involved 41 children and adults with coeliac disease and 11 adults with dermatitis herpetiformis adhering to a gluten-free diet for 8 years on average. Thirty-five newly diagnosed coeliac patients at diagnosis and 6 to 24 months after the start of a gluten-free diet and 27 non-coeliac patients with dyspepsia were investigated for comparison. Daily dietary gluten and wheat starch intake were calculated. Small-bowel mucosal villous architecture, CD3+, alphabeta+, and gammadelta+ intraepithelial lymphocytes, mucosal HLA-DR expression, and serum endomysial, reticulin, and gliadin antibodies were investigated. RESULTS: Forty of 52 long-term-treated patients adhered to a strict wheat starch-based diet and 6 to a strict naturally gluten-free diet; 6 patients had dietary lapses. In the 46 patients on a strict diet the villous architecture, enterocyte height, and density of alphabeta+ intraepithelial lymphocytes were similar to those in non-coeliac subjects and better than in short-term-treated coeliac patients. The density of gammadelta(+)cells was higher, but they seemed to decrease over time with the gluten-free diet. Wheat starch-based gluten-free flour products did not cause aberrant upregulation of mucosal HLA-DR. The mucosal integrity was not dependent on the daily intake of wheat starch in all patients on a strict diet, whereas two of the six patients with dietary lapses had villous atrophy and positive serology. CONCLUSION: Wheat starch-based gluten-free flour products were not harmful in the treatment of coeliac disease and dermatitis herpetiformis.     

Gastrointestinal Symptoms Rating Scale in Coeliac Disease Patients on Wheat Starch-based Gluten-free Diets

Background: A wheat starch-based gluten-free diet is widely adopted in the treatment of coeliac disease, even though the products contain trace amounts of gluten. The aim here was to establish whether such a diet sustains abdominal symptoms. Methods: The Gastrointestinal Symptom Rating Scale (GSRS) was applied to 58 coeliac disease patients on gluten-free diets and 110 non-coeliac controls. An estimate was made of daily dietary fibre and wheat starch-derived gluten. Psychological well-being was evaluated by a structured interview. Twenty-three coeliac patients consented to small-bowel biopsy. Results: The mean GSRS score in coeliac disease patients did not differ from that in control subjects. Poorer psychological well-being was associated with abdominal symptoms in coeliac patients, whereas the daily amount of wheat starch had no effect on GSRS score. Overall dietary compliance was good, and villous atrophy was found in only 2 out of 23 patients. The average fibre consumption, 13 g per day, was lower than recommended. Conclusions: Wheat starch-based gluten-free products are well-tolerated in coeliac disease patients, provided that their diets are otherwise strict.     

Gastrointestinal symptoms rating scale in coeliac disease patients on wheat starch-based gluten-free diets

BACKGROUND: A wheat starch-based gluten-free diet is widely adopted in the treatment of coeliac disease, even though the products contain trace amounts of gluten. The aim here was to establish whether such a diet sustains abdominal symptoms. METHODS: The Gastrointestinal Symptom Rating Scale (GSRS) was applied to 58 coeliac disease patients on gluten-free diets and 110 non-coeliac controls. An estimate was made of daily dietary fibre and wheat starch-derived gluten. Psychological well-being was evaluated by a structured interview. Twenty-three coeliac patients consented to small-bowel biopsy. RESULTS: The mean GSRS score in coeliac disease patients did not differ from that in control subjects. Poorer psychological well-being was associated with abdominal symptoms in coeliac patients, whereas the daily amount of wheat starch had no effect on GSRS score. Overall dietary compliance was good, and villous atrophy was found in only 2 out of 23 patients. The average fibre consumption, 13 g per day, was lower than recommended. CONCLUSIONS: Wheat starch-based gluten-free products are well-tolerated in coeliac disease patients, provided that their diets are otherwise strict.     

Intolerance to cereals is not specific for coeliac disease

BACKGROUND: Abdominal complaints after ingestion of cereals are not uncommon. We assessed how reliable such a history is as a marker for the presence of overt coeliac disease, and whether we should also take into account latent coeliac disease and cereal allergy. METHODS: The study group comprised 93 consecutive adults from health centres spontaneously reporting abdominal symptoms after consumption of cereals. Small bowel mucosal morphology, CD3+, alphabeta+ and gammadelta+ intraepithelial lymphocytes (IELs), HLA DQ alleles and serum IgA-class endomysial (EmA), tissue transglutaminase (tTg) and gliadin (AGA) antibodies were determined. Skin prick and patch tests and serum radioallergosorbent tests for cereals were carried out. Thirty non-coeliac adults served as biopsy controls. RESULTS: Eight (9%) patients had coeliac disease and one mild partial villous atrophy. Altogether 17 had an increased density of gamma delta+ IELs without atrophy. However, only seven (8%) showed evidence of latent coeliac disease, i.e. both an increase in gammadelta+ IELs and the presence of coeliac disease-type HLA. One or more of the allergy tests for cereals was positive in 19; 9 adopted a gluten-free diet and abdominal symptoms were alleviated in all. In non-coeliac patients, serum EmA and tTg tests were negative in all, whereas AGA was seen in 40%. CONCLUSIONS: Intolerance to cereals is not a specific sign of overt or latent coeliac disease. All experimental dietary interventions before proper diagnosis of coeliac disease are therefore to be discouraged. Allergy to cereals, on the other hand, should be considered even in adults.     

Persistent Mucosal Abnormalities in Coeliac Disease Are Not Related to the Ingestion of Trace Amounts of Gluten

Background: It is expected that in patients with coeliac disease the small-bowel mucosal mucosa will return to normal if they adhere to a gluten-free diet (GFD). However, in many this is not the case. This study aims to determine whether this persistent villous atrophy (VA) could be due to continued ingestion of the trace amounts of gluten in `gluten-free' foods, as defined by the WHO/FAO Codex Alimentarius. Methods: Duodenal biopsy specimens from 89 adults with long-standing coeliac disease were examined, and the findings correlated with their form of gluten-free diet. Results: In 51 subjects the duodenal specimen was normal, whereas in 38 there was villous atrophy (partial, 28; subtotal, 8; total, 2). There was no relationship between the presence or absence of VA and ingestion of either a GFD as defined by the Codex Alimentarius (Codex-GFD; 39 patients) or a GFD that contained no detectable gluten (NDG diet; 50 patients). Intraepithelial lymphocyte counts were higher, and lactase levels lower, in subjects with an abnormal biopsy specimen than in those in whom it was normal. However, within each of these biopsy groups there was no difference in these variables between patients on a Codex-GFD and those on an NDG-GFD. IgA antigliadin antibody was detected in 4 of 29 patients on a Codex-GFD and in 3 of 13 on a NDG-GFD (NS). Conclusion: The persistent mucosal abnormalities seen in patients with coeliac disease on a GFD are not due to the ingestion of trace amounts of gluten. The consequences of these abnormalities have yet to be determined.     

Intestinal transglutaminase 2 specific antibody deposits in non-responsive coeliac disease

Background and aims

The diagnosis of coeliac disease is problematic in individuals not responding to a gluten-free diet. Small-bowel villous atrophy occurs in other enteropathies and non-responsive patients are often seronegative. We investigated whether small-bowel mucosal transglutaminase-2 specific autoantibody deposits distinguish non-responsive coeliac disease from other enteropathies.

Methods

Small-bowel mucosal autoantibody deposits were determined in 27 non-responsive, 28 responsive coeliac patients and 10 controls with other enteropathies. Of the non-responsive coeliac patients six were adhering poorly and 21 strictly to the diet; six of the 21 had enteropathy-associated lymphoma, five refractory coeliac disease and 10 otherwise persistent villous atrophy. The presence of mucosal autoantibody deposits was compared to serology, villous morphology, densities of intraepithelial lymphocytes (IELs) and markers of refractory coeliac disease.

Results

Twenty out of 21 well-adhering, all six poorly adhering non-responsive and all 28 untreated responsive coeliac patients had small-bowel mucosal autoantibody deposits present, while controls with other enteropathies were negative. Small-bowel mucosal autoantibody deposits were more accurate in detecting coeliac disease than serology or IEL densities. Refractory coeliac markers revealed only cases with the most severe condition.

Conclusions

Small-bowel mucosal autoantibody deposits differentiate coeliac disease from other enteropathies, enabling the design of appropriate therapeutic strategies.     

Persistent mucosal abnormalities in coeliac disease are not related to the ingestion of trace amounts of gluten.

BACKGROUND: It is expected that in patients with coeliac disease the small-bowel mucosal mucosa will return to normal if they adhere to a gluten-free diet (GFD). However, in many this is not the case. This study aims to determine whether this persistent villous atrophy (VA) could be due to continued ingestion of the trace amounts of gluten in 'gluten-free' foods, as defined by the WHO/FAO Codex Alimentarius. METHODS: Duodenal biopsy specimens from 89 adults with long-standing coeliac disease were examined, and the findings correlated with their form of gluten-free diet. RESULTS: In 51 subjects the duodenal specimen was normal, whereas in 38 there was villous atrophy (partial, 28; subtotal, 8; total, 2). There was no relationship between the presence or absence of VA and ingestion of either a GFD as defined by the Codex Alimentarius (Codex-GFD; 39 patients) or a GFD that contained no detectable gluten (NDG diet: 50 patients). Intraepithelial lymphocyte counts were higher, and lactase levels lower, in subjects with an abnormal biopsy specimen than in those in whom it was normal. However, within each of these biopsy groups there was no difference in these variables between patients on a Codex-GFD and those on an NDG-GFD. IgA antigliadin antibody was detected in 4 of 29 patients on a Codex-GFD and in 3 of 13 on a NDG-GFD (NS). CONCLUSION: The persistent mucosal abnormalities seen in patients with coeliac disease on a GFD are not due to the ingestion of trace amounts of gluten. The consequences of these abnormalities have yet to be determined.     

Endoscopic resection of giant gastrointestinal stromal tumor at the esophagogastric junction: a case report

Background

There is an unmet need for novel treatments, such as drugs or vaccines, adjunctive to or replacing a burdensome life-long gluten-free diet for coeliac disease. The gold standard for successful treatment is a healed small intestinal mucosa, and therefore, the outcome measures in proof-of-concept studies should be based on evaluation of small intestine biopsies. We here evaluated morphometric, immunohistochemical and messenger RNA (mRNA) expression changes in coeliac disease patients challenged with gluten using PAXgene fixed paraffin-embedded biopsies.

Methods

Fifteen coeliac disease patients were challenged with 4 g of gluten per day for 10 weeks and 24 non-coeliac patients served as disease controls. A wide array of histological and immunohistochemical staining and mRNA-based gene expression tests (RT-qPCR and RNAseq) were carried out.

Results

Digital quantitative villous height: crypt depth ratio (VH: CrD) measurements revealed significant duodenal mucosal deterioration in all coeliac disease patients on gluten challenge. In contrast, the Marsh-Oberhuber class worsened in only 80% of coeliac patients. Measuring the intraepithelial CD3⁺ T-lymphocyte and lamina propria CD138⁺ plasma cell densities simultaneously proved to be a meaningful new measure of inflammation. Stainings for γδ T cells and IgA deposits, where previously frozen samples have been needed, were successful in PAXgene fixed paraffin-embedded samples. Messenger RNA extraction from the same paraffin-embedded biopsy block was successful and allowed large-scale qRT-PCR and RNAseq analyses for gene expression. Molecular morphometry, using the mRNA expression ratio of villous epithelium-specific gene APOA4 to crypt proliferation gene Ki67, showed a similar significant distinction between paired baseline and post-gluten challenge biopsies as quantitative histomorphometry.

Conclusion

Rigorous digitally measured histologic and molecular markers suitable for gluten challenge studies can be obtained from a single paraffin-embedded biopsy specimen. Molecular morphometry seems to be a promising new tool that can be used in situations where assessing duodenal mucosal health is of paramount importance. In addition, the diagnostically valuable IgA deposits were now stained in paraffin-embedded specimens making them more accessible in routine clinics.

     

HLA-DQ typing in the diagnosis of celiac disease

OBJECTIVE: More than 95% of celiac patients share the major histocompatibility complex II class human leukocyte antigen (HLA) DQ2 or DQ8 haplotype; patients negative for both types are unlikely to suffer from celiac disease. Our aim was to investigate whether HLA-DQ2 and -DQ8 typing is helpful when diagnosis is uncertain because of the absence of unequivocal small bowel villous atrophy. METHODS: HLA-DQ2 and -DQ8 typing was carried out in 59 patients evincing nondiagnostic small bowel mucosal lesion or positive celiac serology, and in 17 patients maintaining a gluten-free diet without biopsy-proven celiac disease. HLA findings were compared to small bowel mucosal morphology; intraepithelial lymphocytes; and serum endomysial (EmA), reticulin, tissue transglutaminase (anti-tTG) and gliadin antibodies. RESULTS: Of the 59 patients evincing only minor small bowel mucosal changes or positive celiac disease serology, 22 (37%) were negative for DQ2 and DQ8. All EmA-positive patients had celiac-type HLA, but antireticulin antibody, anti-tTg, and antigliadin antibody were also present in HLA-DQ2- and -DQ8-negative individuals. Eleven of 17 patients (65%) observing a gluten-free diet before small bowel biopsy did not share celiac-type HLA. None of the 17 had apparent villous atrophy. Serum EmA and anti-tTG were negative in all. HLA-DQ typing is less expensive than follow-up biopsy in the exclusion of celiac disease. CONCLUSIONS: HLA-DQ2 and -DQ8 determination is useful in exclusion, probably lifelong, of celiac disease in individuals with an equivocal small bowel histological finding. The low specificity of this test must, however, be borne in mind.     

In vivo targeting of intestinal and extraintestinal transglutaminase 2 by coeliac autoantibodies

BACKGROUND: IgA class serum autoantibodies against type 2 (tissue) transglutaminase (TG2) bind to both intestinal and extraintestinal normal tissue sections in vitro, eliciting endomysial, reticulin, and jejunal antibody reactions. It is not known whether similar binding also occurs in coeliac patients in vivo, and may thereby contribute to disease manifestations. AIMS: To investigate intestinal and extraintestinal coeliac tissues for the presence of in vivo bound TG2 specific IgA and its relation to small intestinal mucosal atrophy. PATIENTS: We investigated jejunal samples with normal villous morphology from 10 patients with developing coeliac disease who subsequently progressed to a flat lesion, from 11 patients with dermatitis herpetiformis, and from 12 non-coeliac controls. Six extrajejunal biopsy samples (liver, lymph node, muscle, appendix), obtained based on independent clinical indications from patients with active coeliac disease, were also studied. METHODS: Double colour immunofluorescent studies for in situ IgA, TG2, and laminin were performed. IgA was eluted from tissue sections and tested for TG2 specificity by enzyme linked immunosorbent assay and indirect immunofluorescence. RESULTS: IgA (in one IgA deficient case IgG) deposition on extracellularly located TG2 was detected in jejunal and extrajejunal specimens of all coeliac patients, and also in seven of 11 dermatitis herpetiformis patients, of whom two had no circulating endomysial antibodies. IgA eluted from extraintestinal coeliac tissues was targeted against TG2. CONCLUSIONS: Coeliac IgA targets jejunal TG2 early in disease development even when endomysial antibodies are not present in the circulation. Extraintestinal target sites of coeliac IgA further indicate that humoral immunity may have a pathogenetic role.     

IgA-class transglutaminase antibodies in evaluating the efficacy of gluten-free diet in coeliac disease

OBJECTIVE : Serum IgA-class tissue transglutaminase antibody has proved effective in screening for coeliac disease. The response to a gluten-free diet has been assessed on the basis of small-intestinal morphology. We investigated whether the tissue transglutaminase antibody test could substitute biopsy in this respect, and whether the test is better than the endomysial antibody test in follow-up. DESIGN : Controlled cross sectional, and follow-up study. METHODS : Serum IgA-class tissue transglutaminase antibodies and endomysial antibodies were determined in 87 coeliac adults on a gluten-free diet. All underwent small bowel biopsy, and the mucosal morphology was interpreted along with Marsh's grading 0-3. In 30 patients histological and serological data could be analysed before and after adopting the diet; Marsh 3 was considered inadequate mucosal recovery during the diet. RESULTS : Of the 87 coeliac patients 27 showed Marsh 3 villous atrophy on gluten-free diet; of these 27, tissue transglutaminase antibody was within normal limits in 16 (59%) and endomysial antibody in 20 (74%). Two (7%) out of 29 with normal mucosa (Marsh 0) had positive tissue transglutaminase antibodies. Six (55%) out of 11 admitting regular dietary lapses remained tissue transglutaminase antibody negative. In the follow-up, serum IgA-class tissue transglutaminase antibody was initially positive in 28 (93%) out of 30 untreated patients; even a significant decrease in tissue transglutaminase antibody did not guarantee mucosal recovery. CONCLUSIONS : A substantial number of coeliac patients with negative tissue transglutaminase or endomysial antibodies may still have manifest mucosal villous atrophy. Small bowel biopsy is therefore still necessary to ensure that the gluten-free diet is adequate.     

Searching for coeliac disease in patients with non-alcoholic fatty liver disease

BACKGROUND: A non-negligible percentage of patients with non-alcoholic fatty liver disease, a leading cause of hepatic progressive disorder related to insulin resistance, have no metabolic risk factors, and abnormal intestinal permeability has been suggested to be involved in the pathogenesis of the liver damage. Coeliac disease, a curable disorder characterised by inflammatory mucosal damage, may show hepatic histological features similar to steatohepatitis. Conflicting data have been reported on the prevalence of coeliac disease in non-alcoholic steatohepatitis. AIM: To search for coeliac disease in a series of patients with non-alcoholic fatty liver disease by screening with anti-tissue transglutaminase and anti-endomysium antibodies. PATIENTS AND METHODS: Fifty-nine consecutive patients with hypertransaminasemia and non-alcoholic fatty liver disease, 38 (64%) with steatohepatitis. Anti-endomysium antibodies were assayed by indirect immunofluorescence, IgA anti-tissue transglutaminase by ELISA. Patients who tested positive underwent HLA DQ typing and endoscopy. RESULTS: Tissue transglutaminase antibodies were positive in six (10%) patients and anti-endomysium in two (3.4%); only two (3.4%), positive for both anti-endomysium positive and anti-transglutaminase, resulted to have coeliac disease based on histological findings. After 6 months of gluten-free diet, liver enzymes normalised. CONCLUSIONS: The prevalence of silent coeliac disease is 3.4% in patients with non-alcoholic fatty liver. The inclusion of anti-endomysium antibodies test in studying patients with non-alcoholic fatty liver and persistent biochemical abnormalities has to be taken into account, since positivity for tissue transglutaminase antibodies, in the absence of confirmatory anti-endomysium antibodies, is not sufficient to perform diagnostic endoscopy.     

Coeliac disease among healthy members of multiple case coeliac disease families

BACKGROUND: The main objective of the study was to assess the frequency of undetected coeliac disease among the first-degree relatives of families with two or more previously diagnosed coeliac disease patients. The value of the serum endomysial antibody test as a single means of detecting clinically silent coeliac disease was evaluated. The correlation of endomysial and tissue transglutaminase antibodies and the correlation of endomysial antibodies to the HLA typical for coeliac disease was determined. METHODS: A total of 137 multiple-case coeliac disease families with 872 family members were recruited; 466 healthy family members were simultaneously screened for gliadin and endomysial antibodies and thereafter for tissue tranglutaminase antibodies. Antibody-positive persons were typed for HLA-DQ2 and DQ8. The diagnosis of coeliac disease was based on the typical mucosal lesion on small-bowel biopsies. RESULTS: Forty-four (9.4%) of the healthy family members were positive for endomysial and 48 (10.3%) for gliadin antibodies; 42 biopsies revealed 29 new coeliac disease patients (6.2% of healthy individuals). Endomysial antibodies detected 97% and gliadin antibodies 52% of the new cases. All 44 endomysial-antibody-positive and 35 of 48 gliadin-antibody-positive individuals were positive for DQ2. Tissue transglutaminase antibodies corresponded well with endomysial antibodies. CONCLUSIONS: Undetected coeliac disease is common even among healthy first-degree relatives of multiple case families. The findings emphasize the value of serum endomysial antibodies in the detection of clinically silent coeliac disease. Endomysial-antibody-positive individuals, unlike gliadin-antibody-positive ones, share the coeliac disease-type HLA-DQ.     

Measurements of serum IgA and IgG activities to dietary antigens. A prospective study of the diagnostic usefulness in adult coeliac disease

Serum samples from 458 consecutive adult patients with intestinal symptoms and/or suspected food intolerance were examined for IgG and IgA antibody activities to gluten, egg, and cow's milk antigens by an enzyme-linked immunosorbent assay (ELISA). Increased IgA and/or IgG activities to gluten were seen in 61 patients: 35 had coeliac disease (CD) as suggested by jejunal villous atrophy and subsequent histologic and/or clinical improvement on a gluten-free diet; 4 were previously diagnosed CD patients with clinically suspected dietary failure; 2 had dermatitis herpetiformis with a CD-like intestinal morphology; and 3 had possible gluten intolerance without villous atrophy. The rest had other disorders that might have affected the permeability of the gastrointestinal mucosa or the hepatic IgA catabolism. When the IgA activity to gluten was increased, neither the IgA/IgG activities to nongluten antigens nor the ratio of nongluten to gluten antibodies could discriminate between CD patients and those without CD. However, the median IgA activity to gluten was significantly higher in the CD group. The probability for CD thus increased from 33% in patients with IgA activity to gluten between 0.4 and 0.8 OD units to 90% in those with such activity above 2.4 OD units. Nevertheless, seven untreated CD patients had IgG and IgA activities to gluten within the normal range. ELISA determinations of serum antibodies to gluten antigens are a valuable adjunct in the diagnosis of adult CD, but a negative test does not exclude this disorder.     

Antibodies to recombinant human tissue-transglutaminase in coeliac disease: Diagnostic effectiveness and decline pattern after gluten-free diet

BACKGROUND/AIMS: To assess the sensitivity and specificity of IgA and IgG tissue-transglutaminase antibodies assay, the pattern of antibody decline after gluten withdrawal and their modifications with reference to dietary compliance. SUBJECTS: We studied sera from 143 untreated coeliac children and adolescents (8.8+/-6.1 years), 212 sera from 97 of those patients after gluten withdrawal, and 64 control subjects with non-coeliac intestinal disorders (6.8+/-4.8 years). METHODS: Samples were tested for IgA and IgG class tissue-transglutaminase antibodies by radiobinding assay, using human-derived tissue-transglutaminase, and for IgA anti-endomysium antibodies by indirect immunofluorescence on monkey oesophagus. RESULTS: Untreated coeliac patients had significantly higher titres of IgA and IgG tissue-transglutaminase antibodies than controls (p<0.00001); the diagnostic sensitivity was 95.8% and 99.3%, respectively, and the specificity was 95.3%. Three patients with selective IgA deficiency were positive for IgG tissue-transglutaminase antibodies. The concordance rate between IgA tissue-transglutaminase antibodies and anti-endomysium antibodies was 98.1%. Patients on gluten-free diet showed a significant decrease in IgA and IgG tissue-transglutaminase antibodies with respect to untreated patients (p<0.0001). Tissue-transglutaminase was more sensible than anti-endomysium antibodies to detect small amounts of gluten intake when the compliance was poor. CONCLUSIONS: The recombinant human tissue-transglutaminase antibodies assay is a highly sensitive and specific test for diagnosis of coeliac disease, and it is useful in monitoring the compliance to gluten-free diet.