Marco Di Tola

Anti-tissue transglutaminase antibodies in inflammatory bowel disease: new evidence

Abstract Anti-tissue transglutaminase, previously held to be identical to anti-endomysial antibodies in celiac sprue, has been reported in inflammatory bowel disease patients. To investigate these data further, we evaluated serum and intestinal anti-tissue transglutaminase in inflammatory bowel disease patients, with respect to the Crohn’s disease activity index and the integrated disease activity index. Study population comprised: 49 patients with Crohn’s disease and 29 patients with ulcerative colitis; 45 patients with celiac sprue and 85 autoimmune patients as disease controls; and 58 volunteers as healthy controls. Immunoglobulin A (IgA) anti-recombinant human tissue transglutaminase and anti-endomysial antibody detection in sera and fecal supernatants were performed. Adsorption of positive sera with recombinant human tissue transglutaminase were also performed. Marked increased anti-tissue transglutaminase concentrations were found in celiac sprue, while low-positive values were also found in Crohn’s disease and ulcerative colitis. Anti-endomysial antibodies were detectable only in celiac sprue. Antigen adsorption resulted in a significant reduction of the anti-tissue transglutaminase either in celiac sprue or inflammatory bowel disease sera. A significant correlation between anti-tissue transglutaminase and Crohn’s disease activity index or integrated disease activity index scores was found. Anti-tissue transglutaminase was also detectable in fecal supernatants from inflammatory bowel disease patients. Data highlight that both circulating and intestinal anti-tissue transglutaminases are detectable in inflammatory bowel disease, and that they are related to disease activity. These features underline that, in addition to anti-tissue transglutaminase, an anti-endomysial antibody test is necessary in the diagnostic work-up of celiac sprue, especially in patients with known inflammatory bowel disease.

MR Imaging in the Evaluation of Placental Abruption: Correlation with Sonographic Findings

PURPOSE To evaluate the accuracy of magnetic resonance (MR) imaging and color Doppler ultrasonography (US) in the diagnosis of abruption, to assess the accuracy of the different MR imaging sequences in the visualization of clots, and to evaluate the correlation between MR imaging findings and clinical outcome. MATERIALS AND METHODS This study protocol was approved by the institutional review board, and written informed consent was obtained from all patients. Between March 2008 and June 2010, 60 consecutive patients (mean gestational age, 30.7 weeks [range, 27-38 weeks]; mean age, 29 years [range, 20-38 years]) who were referred for US and MR imaging owing to a putative diagnosis of abruption were assessed. Multiplanar half-Fourier rapid acquisition with relaxation enhancement, true fast imaging with steady-state precession, three-dimensional T1-weighted gradient-echo MR imaging, and sagittal diffusion-weighted MR imaging were performed. Two radiologists independently reviewed each case, resolving by consensus any diagnostic discrepancy. During a second imaging analysis, the same readers randomly and independently assessed the single sequences. The signal intensity of hematoma was correlated with clinical outcome. The reference standard for abruption was the presence of clots and/or fibrin at inspection of the placenta after delivery. The diagnostic efficacy of US and MR imaging was calculated with 95% confidence intervals. Interobserver agreement was assessed by using the Cohen κ test. RESULTS The performance of US and MR imaging was calculated in 39 patients who gave birth less than 10 days after MR imaging; these women were considered to have an adequate reference standard. Abruption was found at delivery in 19 patients. Abruption was identified in 10 of the 19 patients (52%) with US and in all 19 (100%) with MR imaging (P = .002), with an interobserver agreement of 0.949. Diffusion- and T1-weighted sequences helped identify 19 (100%) and 18 (95%) of the 19 abruptions, respectively; interrater agreement was very good for all sequences (κ = 0.892-1.0). Hematomas classified as hyperacute or acute worsened to abruption grade II, with the mother being symptomatic or the fetus distressed. CONCLUSION MR imaging can accurately depict placental abruption, with excellent interobserver agreement, and should be considered after negative US findings in the presence of late pregnancy bleeding if the diagnosis of abruption would change management.

Blockage of T-cell costimulation inhibits T-cell action in celiac disease

BACKGROUND & AIMS Celiac disease is an exemplary model of T cell-mediated pathology. Therefore, therapeutic approaches that target T cells may successfully control this disease. CTLA-4 immunoglobulin (CTLA-4Ig) can inhibit T-cell activation by blocking the engagement of CD28. We took advantage of this tool to define the pathogenic role of gliadin-specific T cells in the induction of celiac disease. METHODS Duodenal biopsy specimens from 7 treated celiac patients were challenged in vitro with gliadin and CTLA-4Ig or CD40-Ig. After 24 hours, the biopsy specimens were analyzed for the presence of characteristic modifications induced by gliadin challenge. RESULTS CTLA-4Ig down-regulated the expression of CD25, intercellular adhesion molecule 1, interleukin 2, and interferon gamma (stained lamina propria mononuclear cells/mm2; P < 0.05) induced by gliadin challenge, caused apoptosis of gliadin-specific T cells (apoptotic T cells/mm2; P < 0.05), and inhibited the production of antiendomysial antibody (P < 0.01). However, it did not control intraepithelial T-cell migration (P = NS) and Fas expression by enterocytes. Conversely, CD40-Ig only controlled production of antiendomysial antibody. CONCLUSIONS In an organ culture model, CTLA-4Ig controls many but not all of the immunologic features of celiac disease.

Adult celiac disease: what is the role of MRI?

To evaluate the ability of MRI to identify intra‐ and extraintestinal findings of celiac disease in an adult population.

Usefulness of the organ culture system in the in vitro diagnosis of coeliac disease: A multicentre study

Objective. Diagnosis of coeliac disease is based on the presence of villous atrophy which recovers following a gluten-free diet. The presence of circulating antiendomysial antibodies as well as their disappearance after a gluten-free diet supports the diagnosis. It has also been demonstrated that antiendomysial antibodies are detectable in supernatants of cultured intestinal biopsies from patients with coeliac disease. The objective of this study was to compare the histology and antiendomysial antibodies in culture supernatants of intestinal biopsies to validate the in vitro organ culture system as a future diagnostic tool for coeliac disease. Material and methods. Seventy-five antiendomysial serum-positive patients on a gluten-containing diet were evaluated. Patients underwent endoscopy with 5 biopsy fragments: 3 for histology, 1 cultured with and the other without gliadin-peptide activator. Antiendomysial antibodies were evaluated in all culture supernatants. Results. Sixty-eight patients had evidence of villous atrophy, while 73 out of 75 were positive to the organ culture system. The agreement rate between organ culture and histology results was 94%. Conclusions. As all the centres participating in the study obtained good agreement between organ culture and histology results, the new system could be considered a reliable tool for the diagnosis of coeliac disease. Nevertheless, it is possible to highlight cases with an organ culture-positive and -negative histology. This feature could be of considerable interest because, as the sensitivity of organ culture seems to be greater than the initial histology, the new system might be useful in uncertain cases where the risk of missing the diagnosis of coeliac disease is high.

Celiac disease diagnosis in misdiagnosed children.

Antiendomysial antibodies (EMA) are today considered the most sensitive and specific serological marker of celiac disease (CD). The aim of the present study was to assess the occurrence of EMA of IgG isotype in EMA IgA negative children with clinical suspicion of malabsorption and their relationship with CD. Serum EMA IgG1 determination was performed on 30 EMA IgA negative children with clinical suspicion of CD. Total serum IgA levels were further investigated. Sixty children with gastroenterological diseases other than CD were used as control disease patients and 63 healthy children were evaluated as the control group. Eighteen out of 30 children in the study showed EMA IgG1 positivity in sera and a villous height/crypt depth ratio <3:1 as index of intestinal atrophy. It is noticeable that a selective IgA deficiency was present in only 9 of 18 EMA IgG1 positive children. In addition, clinical symptoms, EMA IgG1, and mucosal atrophy disappeared after 8–10 mo on a gluten-free diet. Neither EMA IgA nor EMA IgG1 were detected in the children in the control groups. The other 12 children in study group showed no histologic abnormalities and were EMA IgG1 negative. In this study, we reveal a group of EMA IgG1 CD children without IgA deficiency. The diagnosis was based on the presence of gluten-dependent typical serological and histologic features of CD. Our data suggest that EMA IgG1 determination could be a new tool in the diagnostic workup of CD, useful in avoiding possible misdiagnosis.

Celiac Disease: Evaluation with Dynamic Contrast-enhanced MR Imaging

PURPOSE To prospectively determine mural perfusion dynamics in patients with untreated celiac disease by using dynamic contrast material-enhanced magnetic resonance (MR) imaging and to compare these dynamics with those in a control population and in patients with celiac disease treated with a gluten-free diet. MATERIALS AND METHODS Institutional review board approval and informed consent from all participants were obtained. Sixty consecutive patients with untreated celiac disease, 45 patients with celiac disease treated with a gluten-free diet for at least 1 year, and 30 control subjects were enrolled in this study. Dynamic contrast-enhanced MR imaging was performed by using a 1.5-T MR unit. For each MR imaging examination, maximum enhancement, slope of enhancement, and time-signal intensity curves were calculated at the level of the descending duodenal wall. Duodenal wall thickness was also evaluated. Statistical evaluation was performed by using one-way analysis of variance, and the results were confirmed by using the Bartlett test for equal variances and complemented by using Bonferroni multiple comparison, linear correlation, and the Student t test for paired data. RESULTS Mean maximum enhancement of the duodenal wall was significantly higher in patients with untreated celiac disease (229.1 +/- 46.4 [standard deviation]) than in patients with treated celiac disease (109.8 +/- 27.8) and control subjects (94.7 +/- 17.9) (P < .001 for each comparison). All 60 untreated patients showed a curve characterized by fast enhancement and washout (type 4), while all 45 treated patients and the 30 control subjects showed a curve characterized by slow constant enhancement (type 2). Mean duodenal wall thickness was not significantly different between untreated patients (2.2 mm +/- 0.4), treated patients (2.0 mm +/- 0.3), and control subjects (2.0 mm +/- 0.4) (one-way analysis of variance, P = .4177; Bartlett test, P = .6951). CONCLUSION The results of this study suggest that dynamic evaluation of the bowel wall by using contrast-enhanced MR imaging can be an effective and reproducible way to show the inflammation state in celiac disease.

Usefulness of the organ culture system when villous height/crypt depth ratio, intraepithelial lymphocyte count, or serum antibody tests are not diagnostic for celiac disease

The existence of mild forms of celiac disease (CD) can make the histology-based diagnosis difficult to reach. Since anti-endomysium (EMA) and anti-tissue transglutaminase (anti-tTG) are detectable in culture supernatants of duodenal biopsies from CD patients, our aim was to assess if this system can support the histology in the diagnostic work-up. A total of 559 suspected CD patients underwent serum EMA/anti-tTG detection, upper endoscopy with duodenal biopsy sampling, histologic analysis, and organ culture to detect EMA/anti-tTG in supernatants. A subgroup of 30 patients with organ culture positive results were put on a gluten-free diet (GFD). Their gluten-dependency was evaluated by the psychological general well-being and beck depression inventory indexes. Statistical analysis was performed by Cohen k inter-test, Friedman test, and Dunn multiple comparison. Two hundred forty-one out of 559 (43.1%) patients showed intestinal villous atrophy, whereas serum and organ culture EMA/anti-tTG were positive in 293/559 (52.4%) and 334/559 (59.7%) patients, respectively. The strength of agreement resulted good for serology vs histology (k = 0.730), good for organ culture vs histology (k = 0.662), and very good for serology vs organ culture (k = 0.852). After 12 months of GFD, psychological general well-being index significantly increased, and beck depression inventory index significantly decreased (P < 0.001 for each one). Data highlight the organ culture system as a useful tool to assist the histology in diagnosing CD, mainly in cases without villous atrophy or in seronegative patients. The marked improvement in quality of life after a GFD further supports the reliability of this system in diagnosing CD.

Antiendomysial antibody detection in fecal supernatants: in vivo proof that small bowel mucosa is the site of antiendomysial antibody production

OBJECTIVES: Serum antiendomysial antibodies (EMAs), highly sensitive and specific serological markers of celiac disease (CD), are detectable in culture media of biopsy samples from CD patients. This finding can be considered an in vitro evidence that intestinal mucosa is a site of EMA production. To confirm this finding, we investigated the presence of EMAs and of anti-tissue transglutaminase (anti-tTG), recently identified as the autoantigen of the EMA, in fecal supernatants of CD patients. METHODS: Twenty-one newly diagnosed CD patients, 10 treated CD patients on a gluten-free diet, and 14 control disease patients on a gluten-containing diet were enrolled. Twenty-four-hour stool collections and fecal supernatants were obtained from all patients in the study. Biopsy cultures were also performed. IgA EMAs were detected in sera, culture media, and fecal supernatants. IgA, IgG, IgM, and IgE anti-gliadin antibodies (AGAs) and IgA anti-tTG antibodies were measured in fecal supernatants. The weights, water content, and pHs of the 24-h stool collections were also measured. RESULTS: In all untreated CD patients EMAs were detectable in sera, culture media, and fecal supernatants. In treated CD patients, EMAs were detected only in culture media after in vitro gliadin challenge. No EMAs were detected in controls. Anti-tTG levels were higher in untreated CD patients than in treated CD patients and controls. IgA AGA levels were higher in untreated CD patients than in treated CD and control patients, whereas IgM AGAs were higher in both untreated and treated CD patients than in controls. No statistically significant differences were observed for IgG and IgE AGAs among the above-mentioned populations. Fecal weights, water content, and pHs were higher in untreated CD than in control patients. CONCLUSIONS: The presence of EMAs in fecal supernatants represents the in vivo proof that intestinal mucosa is a site of EMA production. Furthermore, EMA detection in the stools could be a simple and useful additional tool to clarify diagnosis in the patchy conditions of CD.

Type 1 diabetes mellitus and celiac disease: endothelial dysfunction

In the observational study cited above, we evaluated whether the presence of undiagnosed CD in a group of adult DM1 patients is associated with a different expression of some hemostatic factors, as well as with a different manifestation and/or progression of microvascular complications in comparison with patients suffering from DM1 only. The Ventura group has carefully examined and commented on this study, but we are only partially in agreement with their observations. First, the including criterion HbA1c B 7.5% or 58 mmol/mol was chosen to ensure the selection of DM1 patients with a satisfactory long-standing metabolic control. This is to prevent that, during the disease progression, an inadequate metabolic control may have affected adversely on the study parameters. The evaluation of hemostatic factors and microvascular complications in DM1 patients also suffering from CD and presenting an unsatisfactory metabolic control could become the object of a future study. Second, we have chosen to assess the metabolic control by means of HbA1c in order to obtain long-standing information reflecting the chronic state that may culminate in microvascular complications. On the other hand, the metabolic control of adult patients with a long-standing DM1 is generally better than that found in diabetic children, to whom the Ventura group refers. This is because children have a shorter disease duration and they are more exposed to factors that can alter their metabolic control. In relation to the other parameters able to evaluate the metabolic control, the diabetologists have obviously considered the presence of frequent hypoglycemic events, the extreme glycemia variability, and the increment in daily insulin needs as an implicit exclusion criterion. Third, in most of the patients evaluated in our study, the presence of other autoimmune diseases has been investigated by means of a wide autoantibody serum panel (data not shown), and the results are not relevant. Finally, since our study was performed on a group of adult DM1 patients, we have obviously not considered anthropometric parameters because the patients enrolled in our study were all already adult, eventually affected by CD, and presenting negative malabsorption clinical picture. It would however be interesting to assess, in the future, the role of CD on hemostatic factors and microvascular complications also in diabetic children. In conclusion, we observed a better metabolic control and a thromboresistant condition in adult patients with both DM1 and undiagnosed CD, even if our opinion is that gluten-free diet is mandatory in all patients suffering from CD.