Coeliac disease in the COVID-19 pandemic: does HLA have a protective effect?

BACKGROUND

The coronavirus disease 2019 (COVID-19), an acute respiratory disease caused by a novel coronavirus (SARS-CoV-2), is emerging as a worldwide public health emergency. Several scientific contributions reported the potential relevance of human leukocyte antigen (HLA) polymorphism and susceptibility to viruses, such as SARS-CoV. In our study, we examined a population of coeliac subjects presenting the HLA haplotype DQ2 and/or DQ8. Our aim was to evaluate whether HLA DQ2 and/or DQ8 haplotype play a role in SARS-CoV-2-infection. The aim was also to evaluate the difficulty in following the gluten-free diet due to all the adversities produced by the pandemic, such as the food supply disruption, and the difficulties in managing the clinical follow-up.

METHODS

191 consecutive coeliac patients completed a questionnaire on their current clinical status, psychological effects, and management of the gluten-free diet experienced during the COVID-19 pandemic and questions regarding possible SARS-CoV-2 infection.

RESULTS

Out of the 191 patients who participated in the study, 42 were full-blown coeliac and 149 were in remission. From the answers provided, 84.8% of patients declared that they no longer consider themselves vulnerable to COVID-19 as they suffer from coeliac disease; 94.2% of patients did not encounter any difficulties in managing the gluten-free diet or in acquiring specific foods and 64.9% of patients in our study underwent diagnostic testing for SARS-CoV-2. Out of this number, 31.5% did so due to contacts with subjects affected by COVID-19, 26.6% for work related reasons, 11.3% due to flu-like symptoms and 30.6% for other reasons. Only 5.8% of the enrolled patients received a diagnosis of COVID-19. Out of all the patients in our population who were diagnosed with COVID-19, 94.8% developed no symptoms and none of them needed hospitalization or intensive care.

CONCLUSION

The hypothesis that the HLADQ2 and/or DQ8 haplotype plays a protective role against SARS-CoV-2 infection, as against other viral infections, is intriguingly suggestive.KEY MESSAGESCOVID-19 as a public health emergency;SARS-CoV-2 and possible complications in coeliac disease;Role of HLA DQ2 and/or DQ8 in SARS-CoV-2 infection.

Coeliac disease in the COVID-19 pandemic: does HLA have a protective effect?

BACKGROUND

The coronavirus disease 2019 (COVID-19), an acute respiratory disease caused by a novel coronavirus (SARS-CoV-2), is emerging as a worldwide public health emergency. Several scientific contributions reported the potential relevance of human leukocyte antigen (HLA) polymorphism and susceptibility to viruses, such as SARS-CoV. In our study, we examined a population of coeliac subjects presenting the HLA haplotype DQ2 and/or DQ8. Our aim was to evaluate whether HLA DQ2 and/or DQ8 haplotype play a role in SARS-CoV-2-infection. The aim was also to evaluate the difficulty in following the gluten-free diet due to all the adversities produced by the pandemic, such as the food supply disruption, and the difficulties in managing the clinical follow-up.

METHODS

191 consecutive coeliac patients completed a questionnaire on their current clinical status, psychological effects, and management of the gluten-free diet experienced during the COVID-19 pandemic and questions regarding possible SARS-CoV-2 infection.

RESULTS

Out of the 191 patients who participated in the study, 42 were full-blown coeliac and 149 were in remission. From the answers provided, 84.8% of patients declared that they no longer consider themselves vulnerable to COVID-19 as they suffer from coeliac disease; 94.2% of patients did not encounter any difficulties in managing the gluten-free diet or in acquiring specific foods and 64.9% of patients in our study underwent diagnostic testing for SARS-CoV-2. Out of this number, 31.5% did so due to contacts with subjects affected by COVID-19, 26.6% for work related reasons, 11.3% due to flu-like symptoms and 30.6% for other reasons. Only 5.8% of the enrolled patients received a diagnosis of COVID-19. Out of all the patients in our population who were diagnosed with COVID-19, 94.8% developed no symptoms and none of them needed hospitalization or intensive care.

CONCLUSION

The hypothesis that the HLADQ2 and/or DQ8 haplotype plays a protective role against SARS-CoV-2 infection, as against other viral infections, is intriguingly suggestive.KEY MESSAGESCOVID-19 as a public health emergency;SARS-CoV-2 and possible complications in coeliac disease;Role of HLA DQ2 and/or DQ8 in SARS-CoV-2 infection.

Visceral and subcutaneous adipose tissue as markers of local and systemic inflammation: a comparison between celiac and obese patients using MRI

BACKGROUND

Celiac disease (CD) is a systemic inflammatory disease, which primarily affects the gastrointestinal tract. It has been recently demonstrated that adipose-tissue infiltration by proinflammatory immune cells causes a chronic low-grade inflammation in obese patients. Magnetic resonance imaging (MRI) has already proved to be useful in evaluation of inflammatory states. The aim of the present study was to determine whether alterations of visceral and subcutaneous adipose tissue, identified with MRI, could serve as markers of local and systemic inflammation in patients with CD.

METHODS

A pilot study was conducted comparing alterations in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in CD patients vs obese patients and healthy controls. Fifty patients were enrolled and assigned to one of the following groups: Group A: 11 active CD patients; Group B: 11 CD patients in remission; Group C: 16 obese patients; Group D: 12 healthy controls. A 3-T MRI unit was used and T2-weighted TSE images of VAT and SAT were obtained in specific regions of interest. Serum cytokine concentrations (TNF-α, IL-6, adiponectin, leptin, IL-2, IFN-γ) were determined.

RESULTS

There was a significant difference in VAT T2 relaxation time between Group A and B (p < 0.001), A and D (p < 0.01), B and C (p < 0.001). There was a statistically significant difference in SAT T2 relaxation time between Group A and B (p < 0.001), A and C (p < 0.05), A and D (p < 0.001), B and C (p < 0.01). In addition, VAT/SAT T2 relaxation time ratio showed a statistically significant difference between Group A and C (p < 0.05) and between Group B and C (p < 0.01). Only TNF-α and IL-6 significantly correlated with both VAT and VAT/SAT ratio in active CD.

CONCLUSIONS

MRI showed similar increased visceral inflammatory signals in patients with active CD and obese patients. However, subcutaneous inflammatory signals were higher in active CD than in all the other groups. These data show that there is a systemic inflammatory state in active CD, whereas chronic inflammation appears confined to VAT in obesity. These data were only partially confirmed by serological cytokine profiles, which showed less specificity than MRI.

Sporadic pedunculated duodenal adenomas. Clinical presentations and endoscopic management: a case series

The prevalence of sporadic duodenal polyps is estimated to be 0.3%-4.6% in patients referred for an upper endoscopy. Most of patients are asymptomatic (66-80%) at the time of diagnosis though bleeding, anemia and abdominal pain are the most commonly reported symptoms. These are related to the polyp's size, location and histological characteristics. We describe three cases of big, pedunculated nonampullary sporadic duodenal polyps (tubulovillous low-grade dysplasia adenomas) located in the second part of the duodenum and characterized by different clinical presentations, managed in our Endoscopic Unit within one year (between 2016 and 2017). Polypectomies were performed, either piece-meal or en-bloc using various endoscopic instruments. In one of our patients (case 1), a delayed bleeding (36 hours after the procedure) occurred eventually managed conservatively with two units of blood transfusion. In the same patient, in the following months after polypectomy, the pre-procedural state of anemia misclassified as Mediterranean anemia has improved with a significant rise of hemoglobin value (14.1g/dl). In a patient who previously underwent a renal transplant (case 2), endoscopy was indicated, based on the positive fecal occult blood test. In another patient (case 3), a big polyp induced pancreatitis since it exerted a strong traction on the duodenal wall during peristaltic movements. The removal of the polyp has led to the resolution of pancreatitis and associated symptoms.

Impact of gluten-free diet on quality of life in celiac patients

BACKGROUND AND AIM

Celiac disease (CD) is a common gluten-related disorder, whose only treatment is a gluten-free diet (GFD). Since a unique view on psychological consequences of a GFD still lacks, our aim was to assess the quality of life (QoL) and the depression state in symptomatic CD patients after GFD. Socio-demographic features were considered.

PATIENTS AND METHODS

210 adult CD patients were recruited and divided into 3 groups : 70 newly diagnosed patients (​Group A​),70 patients who have been on GFD for 6-12 months (​Group B​), and 70 patients who have been on GFD for more than 12 months (​Group C​). We recruited 210 healthy controls (​Group D). Psychological General Well-Being Index (PGWBI) and Beck Depression Inventory (BDI) questionnaires were administered. Each group was evaluated according to age, gender and school ranking.

RESULTS

Groups A ​and B showed lower PGWBI scores compared with both Group C ​and D (p <0.001 for each comparison). Moreover, Groups A and B showed higher BDI scores compared with both ​Group C ​and D (p <0.001 for each comparison).Women, the elderly and the poorly educated seemed to suffer more psychological stress.

CONCLUSION

GFD induces an improvement of well-being and a decrease of depression state after 12 months of strict GFD. Negative psychological implications were observed only in specific risk categories. (Acta gastroenterol. belg., 2016, 79, 447-453).

Nuclear fluorescence serum reactivity on monkey oesophagus: a new antibody for the follow-up of coeliac disease?

We have identified previously a nuclear fluorescence reactivity (NFR) pattern on monkey oesophagus sections exposed to coeliac disease (CD) patients' sera positive for anti-endomysium antibodies (EMA). The aim of the present work was to characterize the NFR, study the time-course of NFR-positive results in relation to gluten withdrawal and evaluate the potential role of NFR in the follow-up of CD. Twenty untreated, 87 treated CD patients and 15 healthy controls were recruited and followed for 12 months. Their sera were incubated on monkey oesophagus sections to evaluate the presence of NFR by indirect immunofluorescence analysis. Duodenal mucosa samples from treated CD patients were challenged with gliadin peptides, and thus the occurrence of NFR in culture supernatants was assessed. The NFR immunoglobulins (Igs) reactivity with the nuclear extract of a human intestinal cell line was investigated. Serum NFR was present in all untreated CD patients, persisted up to 151 ± 37 days from gluten withdrawal and reappeared in treated CD patients under dietary transgressions. Serum NFR was also detected in two healthy controls. In culture supernatants of coeliac intestinal mucosa challenged with gliadin peptides, NFR appeared before EMA. The Igs responsible for NFR were identified as belonging to the IgA2 subclass. The NFR resulted differently from EMA and anti-nuclear antibodies, but reacted with two nuclear antigens of 65 and 49 kDa. A new autoantibody, named NFR related to CD, was described. Furthermore, NFR detection might become a valuable tool in monitoring adherence to a gluten-free diet and identifying slight dietary transgressions.

Antitissue transglutaminase antibodies in acute coronary syndrome: an alert signal of myocardial tissue lesion?

BACKGROUND AND AIM

Antitransglutaminase, previously considered identical to antiendomysial in coeliac sprue (CS), have been reported in end-stage heart failure. To clarify the above-mentioned data, we evaluated these antibodies in a cohort of cardiological patients with respect to troponin I, creatine kinase (CK), MB fraction creatine kinase (CK-MB mass) and myoglobin.

METHODS

Forty-one patients with acute coronary syndrome (ACS), 39 with dilated cardiomyopathy (DCM), 45 with CS and 58 blood donors (BDs) were evaluated. Antitransglutaminase and antiendomysial antibodies were tested in serum of the patients being studied.

RESULTS

High-positive antitransglutaminase values were found in CS, whilst low-positive values were also found in ACS and DCM. In patients at the second ACS, antibody levels were higher than in those at the first cardiac event. In patients with infarct Q, antitransglutaminase were higher than those in infarct non-Q, in which antibody levels were higher than those in unstable angina. A correlation between antitransglutaminase and troponin I, CK, CK-MB mass and myoglobin was found. Finally, antibody levels rose to reach a peak at 30 days from the cardiac event, whereas after further 150 days, approached the values of BDs. Antiendomysial were detectable only in CS.

CONCLUSIONS

Data highlight that antitransglutaminase can occur in cardiological patients, and that these antibodies are related to the severity/extent of the myocardial tissue lesion. This feature suggests a loss of specificity for antitransglutaminase in CS. Furthermore, the possibility of employing these antibodies in the long-term follow-up of ACS, could become an object of interesting discussion.

Prevalence of celiac disease in patients with autoimmune thyroiditis

AIM

Many autoimmune disorders are associated to celiac disease (CD) but the association with autoimmune thyroiditis has been more frequently documented; this is in part explained by a shared immunogenetic make-up, and in part caused to time gluten-exposition, as suggested by the significant correlation observed in celiac patients between the increase occurrence of autoimmune diseases and the length of exposure to gluten. The aim of this study was to establish the prevalence of celiac disease in a group of subjects with autoimmune thyroiditis newly diagnosed on the basis of antibodies anti-peroxidase (TPO).

METHODS

A total of 113 untreated patients with TPO >70 IU/mL were enrolled. CD was screened by measuring anti-endomysial antibodies (EMA) both IgA and IgG; an high prevalence of positive serology was resulting in this group, justified, in part, from EMA IgG investigation.

RESULTS

In fact 31/113 patients showed IgA and/or IgG positivity and were diagnosed as celiacs with jejunal biopsy.

CONCLUSION

On the basis of this paper, such as in according to current research-setting studies, the greater frequency of CD in association to autoimmune thyroid disease suggests that all subjects with TPO should be routinely screened for CD, through EMA IgA and IgG. However, the performance of this screening has never been evaluated until now, even if it could, in fact, be valid in order to increment diagnosis of CD, today still undiagnosed.

Detection of anti-endomysial and anti-tissue transglutaminase autoantibodies in media following culture of oral biopsies from patients with untreated coeliac disease

BACKGROUND AND AIMS

Coeliac disease is an autoimmune disorder characterised by high levels of anti-endomysial and anti-tissue transglutaminase autoantibodies in sera and media of cultured intestinal mucosa biopsies from affected patients. In this study, we wished to investigate whether anti-endomysial and anti-tissue transglutaminase antibodies can also be detected in culture media of oral mucosa specimens, and whether the mouth can be used as an area of immunological testing for coeliac disease.

METHODS

Small intestine and cheek biopsy samples taken from 16 patients with active coeliac disease and from 11 controls were cultured in vitro for 48 h at 37 degrees C in presence of medium alone. Anti-endomysial and anti-tissue transglutaminase were detected in sera and in supernatants of these cultured biopsy samples by indirect immunofluorescence and enzyme immunoassay (EIA), respectively.

RESULTS

Anti-endomysial and anti-tissue transglutaminase were positive in sera of 15/16 coeliac disease patients. Culture media of intestinal mucosa samples from 14/16 coeliac disease patients were anti-endomysial positive, while the same antibodies were positive in supernatants of cultured oral mucosa samples from 15/16 coeliac disease patients. Anti-tissue transglutaminase were positive in both intestinal and oral culture media of 15/16 coeliac disease patients. Neither anti-endomysial nor anti-tissue transglutaminase were found in sera or in culture supernatants of both intestinal and oral biopsy samples from 11 controls.

CONCLUSIONS

Our study suggests a new immunological site to detect the pathognomonic autoantibodies of coeliac disease and confirms that the mouth is involved in this illness.

Chronic abdominal pain associated with intermittent compression of the celiac artery

Recurrent abdominal pain (RAP), surely one of the most frequent causes of medical intervention, is frequently present in many gastrointestinal disease. Usually no structural and/or biochemical alterations can be demonstrated. This condition is, therefore, considered to be due to functional disorders such as irritable bowel syndrome (IBS) or functional dyspepsia. Previous observations suggest the presence of a rare alteration of celiac vessels among the possible causes of RAP. This pathological condition was known as Dunbar syndrome. We report 2 cases of chronic abdominal pain. The former reported weight loss and the latter anemia with iron deficiency. It is remarkable that patients with initial diagnosis of IBS can be affected by celiac disease (CD), which is the cause of their abdominal pain. Our patients were tested for CD; the former was negative and IBS was diagnosed, the latter was positive and a gluten free diet was prescribed. The presence of an epigastric bruit, accentuated during expiration, suggested a possible vascular alteration known as tripod celiac artery compression syndrome. Duplex Doppler sonography suggests the diagnosis of celiac arterial constriction due the diaphragmatic ligament. These cases show that tripod celiac artery compression syndrome might be a cause of RAP and that it may be evaluated and investigated when the clinical examination discloses an abdominal systolic bruit.

Gloves and socks syndrome caused by parvovirus B19 infection

The papular purpuric gloves and socks syndrome (PPGSS) is an uncommon dermatosis with a typical purpuric exanthem limited to hands and feet; it occurs mainly in young adults. We report a case of a 19-year-old man with an acute febrile illness accompanied by purpuric and papular lesions located mostly on the dorsal areas of his hands and feet. Serologic analysis for parvovirus B19 yielded positive results. The diagnosis of PPGSS was made. The eruption cleared without therapy in 12 days with plantar and palmar desquamation. Parvovirus B19 and some other viral infections have been proven to be causative agents of this syndrome.

Evidence of a selective epitope loss of anti-transglutaminase immunoreactivity in gluten-free diet celiac sera: A new tool to distinguish disease-specific immunoreactivities

The aim of the present study was to evaluate the epitope specific humoral human tissue transglutaminase (tTG) immunoreactivity against 3 different human recombinant tTG constructs [(full-length tTG (a.a. 1-687), tTG (a.a. 227-687); tTG (a.a. 473-687)] before and after the introduction of a gluten-free diet (GFD). To this end, sera from 64 celiac disease (CD) subjects on a gluten-containing diet (44 f, 20 m) and after 0.6 +/- 0.3 years and 2.1 +/- 1.3 years of GFD were studied using a quantitative radioimmunoprecipitation assay. All 64 CD patients at diagnosis were full-length anti-tTG (a.a. 1-687)Ab positive. These Abs significantly decreased in frequency and titer after 6 months and 2 years of GFD. However, at low titers, 64.1% (41/64) of CD patients were still fl-tTG (a.a. 1-687)Ab positive after 2 years of GFD. At disease diagnosis, 70.3% (45/64) of the CD patients had Abs directed against fragments (227-687) and/or (473-687) of the tTG protein. This percentage, after 2 years of GFD, significantly decreased to 18.7%, whereas almost 50% of GFD patients had no tTG (227-687) and tTG (473-687) fragment reactivity, but only persistent, low-titer full-length tTG (1-687)Abs. We suggest that the selective loss of immunoreactivity against tTG (227-687) and tTG (473-687) fragments in CD patients with a GFD, could be due to quantitative decrease of autoreactivity driven by tTG-gliadin interaction underlying celiac disease pathogenesis.

Anti-endomysial antibody of IgG1 isotype detection strongly increases the prevalence of coeliac disease in patients affected by type I diabetes mellitus

A strong association between type 1 insulin-dependent diabetes mellitus (IDDM1) and coeliac disease (CD) is well documented, but it is known that prevalence values are underestimated. Serum anti-endomysial antibodies (EMA), considered diagnostic for CD because of their high sensitivity and specificity, belong to the IgA class, but the existence of EMA of IgG1 isotype in the presence or absence of IgA deficiency was reported. In order to re-evaluate the occurrence of CD in IDDM1 patients we performed a screening in IDDM1 patients using EMA of both isotypes. Ninety-four adults affected by IDDM1 (unaffected by CD before enrolling) were enrolled and 83 blood donors as controls. All subjects were on a gluten-containing diet. Histology and biopsy culture were performed. EMA IgA and IgG1 in sera and culture supernatants were detected. Serum EMA were positive in 13 of 94 IDDM1 patients (13.8%). Six of 13 presented IgA-EMA, seven of 13 presented IgG1-EMA. No EMA were found in the control population. Total intestinal atrophy was found in all six patients with serum IgA-EMA and in five of seven with serum IgG1-EMA. Diagnosis of CD was confirmed by histology and organ culture in all 13 patients with serum EMA. The prevalence of CD in the patients affected by IDDM1 was 6.4% for IgA-EMA-positive and 7.4% for IgG1-EMA-positive patients. We confirmed the prevalence of CD in the IDDM1 population obtained with IgA-EMA screening only (6.4%). This prevalence value increases dramatically to 13.8% when IgG1-EMA are also used in the screening. We conclude that IgG1-EMA should also be sought whenever an IDDM1 patient undergoes screening for CD.

Abdominal CT findings may suggest coeliac disease

BACKGROUND

Coeliac disease is the most common gastrointestinal immunological disorder in the western countries. Many adult patients present non-specific symptoms and signs of malabsorption such as chronic diarrhoea, anaemia, weight loss and abdominal distention. In non-specific and doubtful conditions, computed tomography is often the first medical examination performed. In a clinical practice, a critical review of computed tomography signs is therefore mandatory.

AIMS

To evaluate the abdominal computed tomography findings, which are useful to suggest the presence of coeliac disease in adult patients.

PATIENTS AND METHODS

The computed tomography studies of 28 coeliac patients were reviewed, looking for any intestinal and extraintestinal abnormality. The computed tomography findings evaluated were: abnormalities of intestinal fold pattern, bowel dilatation, fluid and air excess, duodenal abnormalities, intestinal intussusception, bowel wall thickening, lymphadenopathy, ascites, intestinal stenosis, mesenteric vascular changes. The abdominal computed tomography of a group of 30 normal subjects was also analysed.

RESULTS

Intestinal fold pattern abnormalities were seen in 23/28 patients. Intestinal dilatation was seen in 21/28. Fluid excess in 18/28 and lymphadenopathy was seen in 12/28 patients; engorgement of mesenteric vessels in 7/28. Bowel wall thickening was observed in 6/28 patients and transient intussusception was observed in 6/28 patients. Increased air content within the bowel in 4/28 and ascites in 2/28 patients. Bowel dilatation together with fluid excess was observed in 18/28 patients. None of the above mentioned abnormalities abnormalities were seen in normal subjects.

CONCLUSIONS

Data of the present study show that several abdominal computed tomography findings may be seen in coeliac adult patients; these findings should be taken into consideration with a high in level of suspicion by radiologists, to avoid diagnostic delay and unnecessary diagnostic and therapeutic procedures.

Celiac disease-associated transglutaminase autoantibody target domains at diagnosis are age and sex dependent

The contribution of age and/or sex to the transglutaminase (tTG) autoantibody response in celiac disease (CD) is not known. To gain insights into transglutaminase humoral autoimmunity at CD diagnosis, our aim was to characterize the autoimmune response against three tTG constructs [(full-length tTG(a.a.1-687), tTG(a.a.227-687), and tTG(a.a.473-687)] and to investigate into its relationship with CD patients' age and sex. One hundred seventy-five newly diagnosed CD patients (115 females and 60 males), subdivided into different groups according to age and sex, were studied using a serum 35S-radioimmunoassay. We found that among full-length tTG autoantibody-positive CD subjects (175/175), 50.9% (89/175) and 83.4% (146/175) had autoantibodies against tTG(227-687) and tTG(473-687) domains, respectively. Female patients of less than 4 years expressed tTG(227-687)Abs in significantly higher percentage and mean autoantibody titers vs. all other groups investigated, and tTG(473-687)Abs in significantly higher titers with respect to adult female patients. Our data identify a subset of CD patients showing a strong humoral tTG immunoreactivity at diagnosis, thus suggesting that age and sex influence the anti-tTG autoantibody response.

123I-Interleukin-2: biochemical characterization and in vivo use for imaging autoimmune diseases

We describe in detail the labelling of interleukin-2 with I ( I-IL2), its biochemical characterization, the binding assay and its use for the detection of tissues infiltrated with mononuclear cells. Human recombinant IL2 was labelled using an enzymatic method and its biochemical characterization was performed using high performance liquid chromatography (HPLC) analysis of cyanogen bromide-cleaved protein. biological and binding assays were performed on CTLL-2 cell line and on activated peripheral blood lymphocytes. studies were performed 1 h after administration of 2-3 mCi of I-IL2 in 10 newly diagnosed type 1 diabetes patients, five pre-diabetic patients, 10 Hashimoto's thyroiditis patients, 10 coeliac disease patients and 10 normal volunteers. I-IL2 scintigraphy allowed the detection and quantification of activated mononuclear cells in several affected tissues. In detail, I-IL2 accumulation was detected in the thyroid of all patients affected by Hashimoto's thyroiditis, in the bowel of all coeliac disease patients and in the pancreas of all pre-type 1 diabetic patients. By contrast, in newly diagnosed type 1 diabetics, I-IL2 scan was positive in five of the 10 studied patients. I-IL2 scintigraphy may be useful for studying autoimmune phenomena and in diagnostic protocols to evaluate the presence of other tissue involvement in patients with an organ-specific autoimmune disease.

[Anti-tissue transglutaminase antibodies in inflammatory and degenerative arthropathies]

Recent studies identified tissue transglutaminase (tTG) as the antigen eliciting antiendomysial antibodies (EMA) in celiac disease (CD). Anti-tTG antibodies have therefore been proposed as a serological test for CD. Nevertheless, IgA anti-tTG but not EMA have also been found in inflammatory bowel disease patients, suggesting that these antibodies are linked to a tissue lesion rather than to an auto-immune component of CD. To confirm this hypothesis, we evaluated the presence of IgA anti-tTG in patients with inflammatory and degenerative diseases, in whom tissue lesions presented far away from the intestinal mucosa. The study was carried out on the serum and synovial fluid (SF) of 68 patients with rheumatoid arthritis (RA=33), psoriatic arthritis (PsA=26) and osteoarthritis (OA=9). In RA, PsA and OA sera, IgA anti-tTG were positive in 33%, 42% and 11% of patients, respectively. Serum anti-tTG levels were significantly higher in RA (p<0.0001), PsA (p<0.0001) and OA (p<0.02) with respect to healthy controls. SF anti-tTG levels were significantly higher in PsA (p<0.018) than in OA. A good correlation between serum and synovial fluid anti-tTG levels was found in all arthropathies This study suggests that tTG is not the only antigen of EMA and, furthermore, that IgA anti-tTG antibodies represent a general lesion-associated event. Moreover, the significant correlation between serum and synovial fluid anti-tTG levels allow us to hypothesise that these antibodies could be synthesized in the site of arthritic lesions.

Antibodies to bovine beta-casein in diabetes and other autoimmune diseases

Cow's milk is thought to be an environmental trigger for autoimmune response in Type 1 diabetes. In the present study, our aim was to investigate the antibody response to bovine beta-casein in different immune- and non-immune-mediated diseases and to establish whether such an antibody response is specific to Type 1 diabetes. We measured antibodies to bovine beta-casein using an enzyme-linked immunosorbent assay in a total of 519 sera from subjects as follows: 71 patients with Type 1 diabetes, 33 patients with coeliac disease, 100 patients with latent autoimmune diabetes in adults (LADA), 50 patients with autoimmune thyroid disease (ATD), 50 patients with Type 2 diabetes, 24 patients with multiple sclerosis (MS), and 3 different groups of controls (n = 191). Significantly increased levels of antibodies to beta-casein were found in patients with Type 1 diabetes, coeliac disease and in LADA compared to age-matched controls (p = 0.01, p = 0.02 and p = 0.01, respectively). No differences were observed in beta-casein antibody titres between patients with other disease conditions (MS, and ATD) and age-matched controls. The highest antibody response to beta-casein in Type 1 diabetic patients and in patients with coeliac disease could reflect the gut mucosal immune disorders common to Type 1 diabetes and coeliac disease. Furthermore, the elevated beta-casein antibody levels found in LADA patients suggest that the antibody response to this protein may be relevant in autoimmune diabetes.

Immunologic evidence of no harmful effect of oats in celiac disease

BACKGROUND

It was recently shown that antiendomysial antibodies (EMAs), which are highly sensitive and specific for celiac disease, are produced by intestinal mucosa. Furthermore, EMAs were detected previously in supernatant fluid from cultured duodenal mucosa specimens collected from untreated celiac disease patients and in culture media of biopsy specimens collected from treated celiac disease patients after an in vitro challenge with gliadin. Moreover, it was recently shown in vivo that oats are not toxic to celiac disease patients, suggesting the safety of oats in a gluten free-diet.

OBJECTIVE

The objective was to better define the controversial role of oats in celiac disease to determine whether oats can be safely included in a gluten-free diet.

DESIGN

We used an in vitro model to test whether oats induce EMA production in supernatant fluid from cultured duodenal mucosa specimens collected from 13 treated celiac disease patients. The biopsy specimens were cultured with and without peptic-tryptic digest (PT) of gliadin and avenin (from oats) and in medium alone. Samples from 5 of the 13 patients were cultured with the C fraction of PT-avenin. Indirect immunofluorescence was used to detect EMAs.

RESULTS

EMAs were detected in specimens from all 13 patients after the challenge with gliadin but not after culture in medium alone. By contrast, no EMAs were detected in any of the specimens cultured with PT-avenin and its C fraction.

CONCLUSIONS

Because the in vitro challenge with PT-avenin and its C fraction did not induce EMA production in treated celiac disease patients, it appears that oats have no harmful effect on celiac disease. Therefore, oats can be safely included in a gluten-free diet.

Radioimmunoassay to detect antitransglutaminase autoantibodies is the most sensitive and specific screening method for celiac disease

OBJECTIVE

The aim of this study was to establish the most sensitive and specific screening method for celiac disease. We tested three methods based on different principles, which all detect autoantibodies against the same antigen (tissue transglutaminase).

METHODS

Sixty-two celiac children at the first biopsy (group 1), 78 celiac children on a gluten-free diet (group 2), 14 celiac children on a gluten-challenge (group 3), and 56 controls with a normal duodenal mucosa (group 4) were studied. The methods used were: 1) radioimmunoprecipitation assay using recombinant tissue transglutaminase (RIA); 2) commercial enzyme immunoassay using guinea pig tissue transglutaminase (ELISA); and 3) indirect immunofluorescence method for detection of antiendomysium antibodies (IF-EMA).

RESULTS

RIA antitransglutaminase autoantibodies were detected in 100% of group 1, 43.6% of group 2, 100% of group 3, and none of the control subjects. ELISA antitransglutaminase autoantibodies were detected in 90.3% of group 1, 9% of group 2, 78.6% of group 3, and in none of the control subjects. IF-EMA were detected in 95.2% of group 1, 11.5% of group 2, 92.3% of group 3, and 1.8% of the controls.

CONCLUSIONS

Our results demonstrate a very high sensitivity and specificity of the RIA method to detect antitransglutaminase autoantibodies in comparison to ELISA and IF-EMA assays. We can explain this finding with the use of human recombinant antigen and the increased capacity of the RIA method to detect low titers of autoantibodies. If our data are confirmed by studies on larger series, tissue transglutaminase RIA could be proposed as the best screening method for celiac patients.

Identification of a new coeliac disease subgroup: antiendomysial and anti-transglutaminase antibodies of IgG class in the absence of selective IgA deficiency

OBJECTIVE

The aim of the present study was to increase the sensitivity of the antiendomysial antibody (EMA) test by evaluating also EMAs of IgG1 isotype.

DESIGN AND SUBJECTS

Over the last 2 years, serum EMAs IgA and IgG1 were determined in 1399 patients, referred to our gastrointestinal unit due to clinical suspicion of malabsorption. Serum anti-tissue transglutaminase (tTG) antibodies IgA and IgG, as well as total IgA levels, were also investigated. Furthermore, EMAs IgA and IgG1 were evaluated in biopsy culture supernatants. Biopsy specimens were also admitted to histological and immunohistochemical evaluation. Twenty-six patients with gastroenterological disease other than coeliac disease (CD) were used as a disease control group. Ninety-nine blood donors were used as a healthy control group.

RESULTS

Diagnosis of CD was based on histological findings in the 110/1399 patients showing EMA IgA positivity, and in a further 56/1399 patients presenting both EMA IgA and IgG1 positivity in sera as well as in culture supernatants. Of the remaining 1233 EMA IgA-negative patients, 60 showed only EMA IgG1 positivity both in sera and in culture supernatants. It is noteworthy that anti-tissue transglutaminase antibodies IgG (anti-tTG) were positive in all 60 EMA IgG1-positive patients as well. By contrast, a selective IgA deficiency was found in only 11 out of the 60 EMA IgG1-positive patients. Villous height/crypt depth ratio was < 3:1 in 38 of the 60 EMA IgG1-positive patients (63.3%), whilst overexpression of ICAM-1 and CD25 was observed in all these patients.

CONCLUSIONS

In this study, we observed a group of CD patients who were EMA IgG1-positive even in the absence of EMA IgA positivity and IgA deficiency. The diagnosis was based on the finding of the gluten-dependent clinical and histological features typical of CD. Data emerging from the present investigation thus suggest that the prevalence of CD should be reassessed and that the determination of EMA IgG1 could offer a new tool in the diagnostic armamentarium of CD.

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.

IgG(1) antiendomysium and IgG antitissue transglutaminase (anti-tTG) antibodies in coeliac patients with selective IgA deficiency. Working Groups on Celiac Disease of SIGEP and Club del Tenue

BACKGROUND

In selective IgA deficiency (IgAD), there is no reliable screening test for coeliac disease (CD).

AIM

To evaluate the usefulness of IgG(1) antiendomysium and IgG antitissue transglutaminase tests for CD diagnosis in IgAD.

METHODS

IgA and IgG antigliadin antibodies (IgA- and IgG-AGA), IgA and IgG(1) antiendomysium antibodies (IgA- and IgG(1)-EMA), and IgA and IgG antitissue transglutaminase (IgA- and IgG-anti-tTG) were assayed in: (a) 20 untreated IgAD/CD patients; (b) 34 IgAD/CD patients on a strict gluten free diet (GFD); (c) 10 IgAD/CD patients not on a strict GFD; (d) 11 untreated CD patients without IgAD; (e) 10 healthy IgAD patients; and (f) 25 healthy controls.

RESULTS

In all untreated IgAD/CD patients, IgG(1)-EMA, IgG-anti-tTG, and IgG-AGA were positive whereas IgA antibodies against these antigens were negative. IgAD/CD patients on a strict GFD did not produce IgG-AGA or IgG(1)-EMA but four of 34 produced IgG anti-tTG. IgAD/CD subjects not on a strict GFD produced IgG-AGA whereas 5/10 and 4/10 were IgG(1)- EMA and IgG-anti-tTG negative, respectively. Untreated CD patients without IgAD were AGA (IgA and IgG), EMA (IgA and IgG(1)), and anti-tTG (IgA and IgG) positive. Healthy controls were AGA and EMA negative whereas two of 10 apparently healthy IgAD subjects and one of 25 healthy negative control were IgG-anti-tTG positive.

CONCLUSIONS

Both IgG(1)-EMA and IgG-anti-tTG tests appear to be useful for identification of IgAD/CD patients whereas they are less satisfactory for monitoring dietary compliance in these subjects. In addition, our findings seem to suggest that IgG-EMA autoantibodies produced by coeliac patients are mainly of the IgG(1) subtype.

Computed tomography of the small bowel in adult celiac disease: the jejunoileal fold pattern reversal

The aim of this retrospective study was to establish whether the distinctive intestinal fold pattern of celiac disease (CD), known by barium studies as jejunoileal fold pattern reversal (JFPR) may be recognized at CT. The number of intestinal folds per 2.5 cm, seen at CT, were counted in the jejunum and in the ileum of 22 adult patients with CD and compared with the folds of 30 consecutive subjects in whom an intestinal disease had been excluded. The results were submitted to statistical analysis by Student's t-test. In the control group the number of folds per 2.5 cm were 4.88 (SD +/- 0.78) in the jejunum and 2.84 ( +/- 0.62) in the ileum; in the CD group the number of folds were 2.42 ( +/- 1.61) in the jejunum and 5.11 ( +/- 1.24) in the ileum. There was a statistically significant difference in the number of jejunal and ileal folds between the CD patients and the control group (in both cases p < 0.001). The JFPR was seen in 15 patients with CD (68.2 %) but in none of the controls. Our study shows that JFPR is not a normal finding and can be demonstrated by CT in the majority of patients with CD.

Imaging active lymphocytic infiltration in coeliac disease with iodine-123-interleukin-2 and the response to diet

Coeliac disease is diagnosed by the presence of specific antibodies and a jejunal biopsy showing mucosal atrophy and mononuclear cell infiltration. Mucosal cell-mediated immune response is considered the central event in the pathogenesis of coeliac disease, and untreated coeliac patients show specific features of T-cell activation in the small intestine. Here we describe the use of iodine-123-interleukin-2 scintigraphy in coeliac patients as a non-invasive tool for detection of lymphocytic infiltration in the small bowel and its use for therapy follow-up, and we demonstrate the specificity of binding of labelled-IL2 to activated lymphocytes by ex-vivo autoradiography of jejunal biopsies. 123I-IL2 was administered i.v. [74 MBq (2 mCi)], and gamma camera images were acquired after 1 h. Ten patients were studied with 123I-IL2 scintigraphy at diagnosis and seven were also investigated after 12-19 months of gluten-free diet. Results were expressed as target-to-background radioactivity ratios in six different bowel regions before and after the diet. At the time of diagnosis all patients showed a significantly higher bowel uptake of 123I-IL2 than normal subjects (P < 0.003 in all regions). A significant correlation was found between jejunal radioactivity and the number of IL2R + ve lymphocytes per millimetre of jejunal mucosa as detected by immunostaining of jejunal biopsy (r2 = 0.66; P = 0.008). Autoradiography of jejunal biopsies confirmed that labelled-IL2 only binds to activated T-lymphocytes infiltrating the gut mucosa. After 1 year of the diet, bowel uptake of 123I-IL2 significantly decreased in five out of six regions (P < 0.03), although two patients still had a positive IL2 scintigraphy in one region. We conclude that 123I-IL2 scintigraphy is a sensitive non-invasive technique for assessing in vivo the presence of activated mononuclear cells in the bowel of patients affected by coeliac disease. Unlike jejunal biopsy, this method provides information from the whole intestine and gives a non-invasive measure of the effectiveness of the gluten-free diet.

31-43 amino acid sequence of the alpha-gliadin induces anti-endomysial antibody production during in vitro challenge

BACKGROUND

Wheat gliadin is the culprit antigen of coeliac disease (CD). Two short sequences of NH2-terminal portion of gliadin seem to be responsible for CD. Antiendomysial antibodies (EMA), highly sensitive and specific for CD, are detectable in the culture media from treated CD patients, after in vitro challenge with peptic-tryptic (PT) digest of gliadin. In this study we detected EMA production after in vitro challenge with 31-43 peptide. We used 56-68 peptide, lacking toxic sequences, as a negative control.

METHODS

Duodenal samples from 11 treated CD patients and 9 control patients were cultured with 31-43 and 56-68 peptides and PT gliadin. Indirect immunofluorescence analysis was used for EMA detection.

RESULTS

EMA were detected in culture media of 10 of 11 specimens challenged with PT-gliadin and in the media of all specimens challenged with 31-43 peptide. No EMA were detectable in any treated patients cultured with 56-68 peptide or with medium alone. No EMA were observed in cultures of control specimens.

DISCUSSION

The ability of the 31-43 sequence of the alpha-gliadin to induce EMA production suggests its involvement in the pathogenesis of CD. Furthermore, it may be a more useful antigenic substance than PT gliadin for both in vitro and in vivo studies of CD.

Quantitative analysis of stool losses in adult celiac disease: use of near-infrared analysis reconsidered

BACKGROUND

An attempt has been made to establish whether near-infrared stool analysis is more suitable for quantifying malabsorption than the traditional stool fat analysis. A group of celiac disease (CD) patients was used as index population.

METHODS

Stool fat, nitrogen, and water were measured with near-infrared analysis of 1- and 3-day stool collections in 96 celiac disease patients on a free diet (in 39 also on gluten-free diet) and in 96 matched controls and 14 patients with latent CD.

RESULTS

The fecal output of fat, nitrogen, and water was significantly increased in free-diet CD, whereas their percentage content was only slightly modified compared with controls. None of the variables under consideration differed significantly between the 24-h and 72-h stool specimens.

CONCLUSION

Our data show that the high value of fecal fat, nitrogen, and water, in celiac disease, are mainly due to the fecal weight, whereas the percentage composition of stool does not offer additional diagnostic information. Furthermore, 3-day stool collection is not necessary to confirm or rule out malabsorption in most patients. Near infrared analysis of 24-h specimens is time- and cost-effective and may increase the use of stool analysis and be usefully employed to monitor the clinical follow-up of patients with chronic diarrhea.

Evaluation with Doppler sonography of mesenteric blood flow in celiac disease

OBJECTIVE

The aim of this study was to investigate with Doppler sonography the variations of resistance in the superior mesenteric artery, both at fasting and in the postprandial state, in patients with celiac disease.

SUBJECTS AND METHODS

Twenty-five patients with celiac disease (20 women, five men; mean age, 30 +/- 7 years) and 10 healthy volunteers (seven women, three men; mean age, 28 +/- 6 years) were examined with Doppler sonography. Nineteen patients were untreated (no dietary restrictions) and six patients were treated with a gluten-free diet at the time of the examination. Imaging was performed at both fasting and 15 min after an 1890-kJ meal. We introduced a parameter called "resistive difference," defined as the mathematic difference between the resistive index measured at fasting (highest value) and that measured at 15 min after the meal (lowest value) as a way to express the postprandial resistive change in the superior mesenteric artery.

RESULTS

Untreated patients with flat mucosa showed a resistive difference of 0.03 +/- 0.05, followed by untreated patients with mucosal subatrophy (0.05 +/- 0.04), treated patients (0.09 +/- 0.02), and healthy volunteers (0.12 +/- 0.04). A statistically significant difference was noticed between the resistive difference of healthy volunteers and both those of the untreated patients with subatrophy (p = .016) and of the patients with complete atrophy (p = .011), as well as between the resistive difference of the treated patients and both those of the untreated patients with subatrophy (p = .021) and of the patients with complete atrophy (p = .020).

CONCLUSION

We believe that Doppler measurement of resistive difference in the superior mesenteric artery can be an effective way to express severity of celiac disease and to document its regression after diet therapy.

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.

Angiotensin-converting enzyme activity in stools of healthy subjects and patients with celiac disease

Angiotensin-converting enzyme (ACE) is a dipeptidylcarboxypeptidase that occurs in three types of cells: endothelial, epithelial, and neuroepithelial. ACE activity is present in plasma, urine, and vascular endothelium. High levels of ACE are found in the brush border of human small bowel. The aim of this study was to evaluate ACE activity in human stools and to find a correlation with the intestinal loss of epithelial cells. Fifteen healthy subjects (HS) (8 males, 7 females; age range 6-56 years), 20 patients with celiac disease (CD) (11 males, 9 females; age range 15-53 years), and 18 patients with CD in remission after a gluten-free diet (CD-GFD) (8 males, 10 females; age range 14-54 years) were enrolled in the study. The fecal ACE activity was measured in all groups. Fecal samples were kept at -20 degrees C for a subsequent test. In HS, fecal ACE activity was 21.03 +/- 16.17 nmol/min/100 g (mean +/- SD). In patients with CD with subtotal mucosa atrophy, ACE activity was significantly higher (113 +/- 88.94) than in HS and CD on GFD (36.65 +/- 23.9). We have demonstrated ACE activity in human stools. ACE activity in stools seems to derive from the microvilli of the intestinal mucosa, thus suggesting the potential usefulness of ACE determination as an index of enterocyte damage.

Production of antiendomysial antibodies after in-vitro gliadin challenge of small intestine biopsy samples from patients with coeliac disease

BACKGROUND

Diagnosis of many immune-mediated diseases is helped by detection of antibodies directed against the pathogenetic (self or foreign) antigen. In coeliac disease (CD), we have a situation in which antiendomysial antibodies (EMA), which are not specific for the pathogenetic antigen, reach a specificity and sensitivity of detection of CD approaching 100%, whereas detection of antibodies against gliadin (AGA), the pathogenetic antigen, is far less specific and sensitive in diagnosis. No direct evidence of a relation between gluten/gliadin challenge and EMA production exists. We tried to establish whether the small intestine of CD patients is the site of EMA production and whether gliadin challenge could induce their release.

METHODS

Small intestine biopsy samples from treated (23) and untreated (16) CD patients and controls (18) were cultured in vitro for 24-48 h in the presence of gliadin, another alimentary antigen, or medium. EMA and AGA were detected in the supernatants of these organ culture biopsy samples by ELISA and immunofluorescence technique, respectively.

FINDINGS

No EMA were found in the culture supernatants of biopsy samples of 18 controls, whereas they were detected in the culture supernatants of all 16 untreated CD patients irrespective of gliadin challenge. Conversely, EMA were not detected in supernatants of biopsy samples cultured in medium only from 23 treated CD patients, but were detected in 17 of the 23 biopsy samples challenged with gliadin.

INTERPRETATION

Our results suggest that a more complex pathogenetic mechanism than normally accepted is involved in CD. Furthermore, our findings raise the possibility that EMA, or the antigen recognised by them, are involved directly in the pathogenesis of CD.

Gluten-sensitive disease with mild enteropathy

BACKGROUND & AIMS

Celiac disease is a permanent gluten intolerance strongly associated with HLA class II antigens and possibly showing milder changes of mucosal architecture. Ten patients with symptoms suggesting celiac disease and serum antiendomysium antibodies with normal mucosal architecture were studied.

METHODS

Immunohistochemical detection of mucosal immune activation and HLA typings were performed.

RESULTS

Mucosal immune activation, with normal mucosal architecture and normal gamma/delta+ intraepithelial lymphocytes counts, was found on a gluten-containing diet. In 3 of 6 patients, multiple biopsy specimens showed one sample with severe villous atrophy. Clinical and immunomorphologic features were strictly gluten dependent. The mucosal immune activation was elicited in vitro by gliadin. Only 4 patients had the typical HLA typing of celiac disease.

CONCLUSIONS

Gluten-sensitive celiac-like symptoms may occur in patients with serum antiendomysium antibodies, apparently normal intestinal mucosa, and HLA typing not commonly associated with celiac disease. These patients should undergo multiple biopsies, and signs of immunologic activation should be sought accurately; in the presence of mucosal immune activation, a trial with a gluten-free diet should be encouraged to detect gluten dependency. In vitro immunologic response of small intestinal mucosa to gliadin may support the diagnosis of gluten-sensitive enteropathy.

Frequency and clinical pattern of celiac disease among siblings of celiac children

To investigate the prevalence and clinical and genetic patterns of celiac disease (CD) among siblings of CD patients, 103 siblings and one twin of 80 celiac children were evaluated by means of their clinical history, physical examination, blood indices of nutritional status, and antigliadin antibodies (AGA). Antiendomysium antibody (AEA) levels were determined in 70 patients and 85 subjects were human leucocyte antigen (HLA) typed. On the basis of clinical or laboratory data or both, 21 siblings (20.2%) were submitted to intestinal biopsy, whereas intestinal biopsy in six siblings with positive serologic screening (AGA IgA or AEA or both) was not performed because of parental refusal. In a high percentage of cases (18%), all on a gluten-containing diet, the intestinal mucosa was atrophic, and CD was subsequently diagnosed. Because we could not submit all the siblings to intestinal biopsy, this figure could underestimate the real prevalence of the disease in our series; consequently, it was not possible to calculate accurately the sensitivity and specificity of AGA and AEA. Nevertheless, AEA (positive in all the nine siblings with mucosal atrophy), followed by AGA IgA, proved to be the best screening for CD. Eighteen of 19 CD siblings showed HLA-predisposing antigens. Among the 19 CD siblings, one showed a typical form with gastrointestinal symptoms, two had short stature, one suffered from recurrent vomiting, and in 15, the disease was clinically silent. On the contrary, among siblings who were first diagnosed (index cases), the majority (73.7%) had a typical form of CD, and no clinically silent cases were observed. We did not find any difference between index cases and CD siblings in food habits and distribution of HLA antigens. In 15 of 18 cases, the sibling diagnosed subsequently was the older one. Finally, the typical form of CD was significantly more frequent among the younger brother than the older. In conclusion, the high prevalence of the silent form of CD in our cases indicates that siblings of CD subjects should always be screened for CD. The combination of AGA IgA and AEA represent a good screening method to use in selecting children for the intestinal biopsy.

Definition of the initial immunologic modifications upon in vitro gliadin challenge in the small intestine of celiac patients

BACKGROUND & AIMS

Mucosal cell-mediated immune response is considered the central event in the pathogenesis of celiac disease. In cultured intestinal explants from celiacs in remission, we have characterized the early stages of gliadin-induced immune activation.

METHODS

Intestinal biopsy specimens (15 treated celiacs and 13 controls) were cultured with gliadin or maize prolamine digests for 24 hours as well as for 1, 2, 4, 6, 8, and 12 hours in some subjects. The expression of immunologic markers was detected by immunocytochemistry.

RESULTS

Gliadin challenge may initiate two parallel pathways, one of which leads to T-cell activation and another that precedes it. Epithelial cells overexpress DR molecules after 1 hour, and in a second stage T lymphocytes become fully activated. Moreover, T lymphocytes migrate in the upper mucosal layers. T lymphocytes that migrate in the higher lamina propria compartments are mainly CD4+ and show markers of activation; migrating intraepithelial lymphocytes are CD8+ and do not express these markers.

CONCLUSIONS

In vitro gliadin challenge is a suitable model to reproduce various immunologic features of celiac lesions; these may be caused by different pathways. The comprehension of these phenomena is essential to clarify the distinctive pathogenic mechanisms leading to disease and may help in defining novel therapeutic approaches.

In vitro activities of A-gliadin-related synthetic peptides: damaging effect on the atrophic coeliac mucosa and activation of mucosal immune response in the treated coeliac mucosa

BACKGROUND

Gliadin amino acid sequence(s) responsible for toxicity in susceptible individuals have not been fully elucidated. Previous in vitro studies have suggested the presence of active sequences in the NH(2)-terminal part of the A-gliadin molecule. In this paper the in vitro activity of A-gliadin synthetic peptides 31-55, 31-43, and 44-55 has been investigated.

METHODS

Organ culture of jejunal mucosa from untreated and treated coeliac patients was used. In the first system enterocyte height was used as a measure of peptide toxicity; in the second system evidence of activated mucosal cell-mediated immune response was sought.

RESULTS

Peptides 31-55 and 31-43 were active on untreated coeliac mucosa at a concentration of 0.5 mg/ml and peptide 44-55 only at a concentration of 3 mg/ml. In in vitro-cultured treated coeliac mucosa peptides 31-55 and 31-43 at 1 mg/ml and peptide 44-55 at 3 mg/ml were able to induce enhanced epithelial expression of HLA-DR and 4F2 molecules and the appearance of CD25 positive cells.

CONCLUSIONS

Our results suggest that 31-43 and 44-55 A-gliadin peptides are both active, even if to different extents. In vitro systems remain essential tools to screen material to be subsequently tested in vivo.

Use of a threshold serum level of anti-gliadin antibodies improves diagnostic efficiency of the test in adult coeliac disease but is unreliable as a screening test

Measurement of anti-gliadin antibodies is considered a highly sensitive test for coeliac disease in children. Specificity, however, appears to vary due to the presence of anti-gliadin antibodies in other diseases. Sensitivity and specificity of anti-gliadin antibody measurement for coeliac disease in adults has, thus, been assessed using the ratio of the densitometric unit test/the mean +3SD of densitometric unit values of a pool of sera of healthy biopsy-proven controls. Anti-gliadin antibodies-A and G were measured separately with an enzyme-linked immunosorbent assay in 64 coeliacs (20 males; 44 females; age range 14-71 years) with diagnosis confirmed at jejunal biopsy; and in 60 controls (25 males; 35 females; age range 16-69 years) with normal jejunal biopsy. Detection of anti-gliadin antibodies-A and G had a sensitivity of 58% and 61%, respectively, and a specificity of 85% and 94%. For the procedure a Receiver Operating Characteristic analysis was used. Considering anti-gliadin antibodies-A and G values of at least 0.9 densitometric unit, sensitivity was 50% and 60%, respectively, whereas specificity was 100% for both. These findings confirm the low sensitivity of these measurements in adult coeliacs and thus the unreliability for screening. The high specificity, when using a threshold value of 0.9 densitometric unit, may be useful in the evaluation of adults with suspected coeliac disease.

Quantitative determination of faecal fat, nitrogen and water by means of a spectrophotometric technique: near infrared reflectance analysis (NIRA). Assessment of its accuracy and reproducibility compared with chemical methods

Measurement in faeces of the principal nutrients, fat (F), water (W) and nitrogen (N) is useful to assess digestive and absorptive functions and thus to monitor patients' progress and response to therapy in malabsorption/maldigestion syndromes. Presently available techniques are not ideal in clinical practice for serial analysis as they are time-consuming and require unpleasant and prolonged handling of the stools. The present study aimed to evaluate the accuracy and precision of near infrared reflectance analysis (NIRA) in routine measurement of fat, nitrogen and water faecal contents compared with Van de Kamer (VDK), Kjeldahl (KJ) and gravimetric-by-lyophilization (LY) methods, respectively. Fat, nitrogen and water (n = 34), were measured in the 1-day faecal collections of 15 healthy subjects and 19 patients (10, coeliac disease; 6, chronic pancreatitis; 3, small-bowel Crohn's disease). A highly significant linear correlation was found between VDK, KJ, LY methods and NIRA analysis. Very low values of intra-assay coefficient of variation indicated a remarkable analytical precision of NIRA. A recovery test at different concentrations in the useful range was performed for all three nutrients, to assess the accuracy of NIRA. Quantitative recoveries were between 95 and 105%. Data from the present study show that NIRA analysis is reproducible, accurate and rapid (less than 1 min). These characteristics make NIRA serial analysis useful in clinical practice to monitor progress and response to therapy in patients with malabsorption/maldigestion syndromes.

[Radiological study of the duodenum in celiac disease in adults]

Celiac disease (CD) is the most common form of malabsorption in childhood when it presents with diarrhea and growth failure, a jejunal biopsy is considered the first diagnostic investigation by some authors. In adulthood, clinical symptoms of CD may mimic several different disease, such as peptic ulcer and IBS, and the first diagnostic investigation is an upper GI series. Radiological features of duodenum and small bowel were evaluated in twenty patients with adult onset celiac disease. Sign of duodenitis such as thickened folds, mucosal nodules, dilatation of duodenum and erosions were observed in 19 out of our 20 patients (95%); particularly, thickened folds in 17 (85%), nodularity in 16 (80%), duodenal dilatation in 12 (60%) and erosions in 4 (20%). In celiac disease the lesions are more severe in the upper part of small bowel, and duodenitis may be the unique sign of CD. Duodenitis may be part of a disease involving the entire small bowel; so, a duodenitis observed in the upper gastrointestinal tract requires the study of the entire small bowel--which seems to be very important in the case of celiac disease.