Wahiba Sakly

Anti-Saccharomyces cerevisiae Antibodies are Frequent in Type 1 Diabetes

Anti-Saccharomyces cerevisiae antibodies (ASCA) have been described in many autoimmune diseases in which there is an increased intestinal permeability. Also in type 1 diabetes (T1D), there is an increased intestinal permeability. Since no data are available about ASCA in T1D, we evaluated, retrospectively, the frequency of ASCA in this disease. ASCA, IgG, and IgA, were determined by ELISA in sera of 224 T1D patients in which coeliac disease has been excluded and 157 healthy control group. The frequency of ASCA (IgG or IgA) was significantly higher in T1D patients than in the control group (24.5% vs. 2.5%, p < 10−7). The same observation was found in children and in adult patients when we compare them to healthy children and blood donors group respectively. Compared to children, adult patients with T1D showed significantly higher frequencies of ASCA of any isotype (38% vs. 13.7%, p < 10−4), both ASCA IgG and IgA (12% vs. 1.6%, p = 0.002), ASCA IgG (35% vs. 9.8%, p < 10−5) and ASCA IgA (15% vs. 5.6%, p = 0.001). The frequency of ASCA was statistically higher in females of all T1D than in males (30.8% vs.17.7%, p = 0.03), in girls than in boys (22% vs.6.2%, p = 0.017), and significantly higher in men than in boys (35.7% vs. 6.2%, p < 10−4). The frequency of ASCA IgG was significantly higher than that of ASCA IgA in all T1D patients (21% vs. 9.8%, p < 0.002), in all females (26.5% vs. 10.2%, p < 0.002), in women (37.9% vs. 12%, p < 0.001). The frequency of ASCA was significantly higher in all long-term T1D than in an inaugural T1D (29% vs. 14.5%, p = 0.019). The same observation was found in adults (45.8% vs. 17.8%, p = 0.01). In long-term T1D patients, ASCA were significantly more frequent in adults than children (45.8% vs. 14.5%, p < 10−4). The frequency of ASCA IgG was significantly higher in long-term T1D than in an inaugural T1D (25.2% vs. 11.6%, p = 0.03). Patients with T1D had a high frequency of ASCA.

IgA anti-transglutaminase antibodies as a tool for screening atypical forms of coeliac disease in a French at-risk paediatric population.

Objective The diagnosis of coeliac disease (CD) is often delayed because many children are free from the major symptoms characteristic of this enteropathy. The aim of the present study was to determine the efficacy of antibodies directed against tissue transglutaminase (tTG Abs) for early detection of CD in a population with few symptoms of the disease, as well as in children with an autoimmune disorder. Methods This was a prospective study in a paediatric population including 638 patients with clinical symptoms frequently associated with CD, autoimmune diseases such as type 1 diabetes mellitus (DM1), autoimmune thyroiditis or hepatitis, and Turners syndrome. Anti-endomysium, tTG Abs and antigliadin antibodies were analysed in these patients using an indirect immunofluorescence technique and enzyme-linked immunosorbent assay techniques. Intestinal biopsies were performed for some patients with positive or negative antibodies. Results tTG Abs were detected in 2.6% of children with symptoms associated with CD, such as digestive signs and growth failure, and in 5.4% of children with DM1. No other autoimmune disease was positive for tTG Abs. Biopsies performed in the patients with positive tTG Abs showed mucosal atrophy confirming the diagnosis of CD in all cases. Conclusion Children displaying minimal symptoms frequently associated with CD and children with DM1 should be systematically screened for tTG Abs.

Localization of tissue transglutaminase and N (epsilon)-(gamma) -glutamyl lysine in duodenal cucosa during the development of mucosal atrophy in coeliac disease

Expression and transamidation activity of tissue transglutaminase (tTG) may be involved in the morphological modifications leading to the mucosal atrophy observed in coeliac disease (CD). We aimed to investigate the localization of tTG within the duodenal mucosa during the development of villous atrophy. The localization and level of expression of Nɛ-(γ-glutamyl) lysine isopeptides which could reflect the transamidation activity of tTG were also analyzed. tTG and Nɛ-(γ-glutamyl) lysine were localized using an immunohistochemical technique on duodenal biopsies obtained from 75 patients with CD and 51 subjects with normal mucosa (control group). The number of cases displaying tTG-expressing cells in the basement membrane and lamina propria was significantly higher in CD patients than in the control group. Moreover, the intensity of tTG staining in these areas was higher in CD. In contrast, the number of biopsies with tTG-expressing enterocytes was significantly lower in CD than in the control group. There was no difference in Nɛ-(γ-glutamyl) lysine between the two populations. Tissue transglutaminase was differently expressed in the various areas of the mucosa according to the stage of atrophy, whereas the localization and the intensity of the labelling of Nɛ-(γ-glutamyl) lysine isopeptides did not show any modification. The preferential localization in the basement membrane and lamina propria may reflect the involvement of tTG in the development of mucosal atrophy in CD.

Performance of anti-deamidated gliadin peptides antibodies in celiac disease diagnosis.

OBJECTIVES To assess the usefulness of anti-deamidated gliadin peptides antibodies (a-DGP), in the diagnostic of celiac disease (CD). PATIENTS AND METHODS One hundred and three untreated CD patients (67 children and 36 adults) and 36 celiac patients under gluten-free diet were studied. Two hundred and seventy-four subjects served as controls (114 healthy blood donors, 80 healthy children and 80 patients with primary biliary cirrhosis). a-DGP (IgG and IgA) and anti-tissue transglutaminase antibodies (AtTG) were detected by enzyme-linked immunosorbent assay (Elisa). Anti-endomysium antibodies (AEA) were detected by indirect immunofluorescence on human umbilical cord. RESULTS The sensitivitiy of IgG and IgA a-DGP were 94% and 97% respectively, compared to 96% for AEA and AtTG. The specificity of a-DGP was 93.6% for IgG and 92% for IgA. The specificity of AEA and AtTG were 100%. The frequency of IgG and IgA a-DGP was significantly higher in patients with CD than in control group (94% vs. 4.4%, P<10(-7); 97% vs. 8%, P<10(-7)). The frequency of IgG a-DGP was the same in children and adult (94%). The frequency of IgA a-DGP were similar in children and adults (95.5% vs. 100%). CONCLUSION Our study shows that a-DGP increases neither the sensitivity nor the specificity of AEA and AtTG.

High Frequency of Antiphospholipid Antibodies in Primary Biliary Cirrhosis

To evaluate, retrospectively, the frequency of autoantibodies of antiphospholipid syndrome (APLS) in Tunisian patients with primary biliary cirrhosis (PBC).

Anti-Saccharomyces cerevisiae Antibodies Are Elevated in Graves' Disease But Not in Hashimoto's Thyroiditis

Background. Anti-Saccharomyces cerevisiae antibodies (ASCA) had been known to be specific for Crohn’s disease, but they had also been found in many other autoimmune diseases. Aim. The aim of this study was to evaluate the prevalence of ASCA in patients with autoimmune thyroid disease (AITD). Patients and Methods. One hundred and ninety-seven patients with AITD and 160 healthy controls were included in the study. One hundred and nineteen patients had Graves’ disease (GD) and 78 patients had Hashimoto’s thyroiditis (HT). ASCA IgG and IgA were determined by ELISA. Results. ASCA IgG were significantly more frequent in patients with GD than in control group (11.8% vs. 3.1%, p = 0.002). In HT, the frequency of ASCA IgG was similar to that of the control group (3.8% and 3.1% respectively). The frequency of ASCA IgA was similar in GD (0.8%), HT (2.6%), and the control group (3.1%). In all GD patients, the frequency of ASCA IgG was significantly higher than that of ASCA IgA (11.8% vs. 0.8%, p = 0.001). These results were also true even in male and female groups (10.4% vs. 1.3%, p = 0.01 and 14.3% vs. 0%, p = 0.01, respectively). ASCA IgG levels were significantly higher in GD patients (6.7 ± 11.1 vs. 2.2 ± 2.8, p = 3 × 10−6) and in HT patients (4.2 ± 4.7 vs. 2.2 ± 2.8, p = 0.0002) than those in the control group. ASCA IgA levels were comparable among patients with GD, HT, and the control group. In GD patients, the mean titer of ASCA IgG was significantly higher than that of ASCA IgA (6.7 ± 11.1 vs. 3.6 ± 4.2, p = 0.005). Conclusion. Patients with GD had a higher frequency of ASCA IgG than controls.

Thyroid-Related Autoantibodies in Tunisian Patients with Type 1 Diabetes

Aim. To evaluate, retrospectively, the frequency of antithyroid antibodies (ATA) in patients with type 1 diabetes (T1D). Materials and methods. Antithyroperoxidase antibodies (TPO-Ab), antithyroglobulin antibodies (TG-Ab), and antithyroid-stimulating hormone receptor antibodies (TSHR-Ab) were determined by enzyme-linked immunosorbent assay. Sera of 312 patients (166 children and 146 adults) with T1D were analyzed. Sera of 276 healthy subjects (87 children and 189 blood donors) served as controls. Results. Out of 312 patients with T1D, 44 (14%) had ATA (TPO-Ab or TG-Ab or TSHR-Ab). The frequency of ATA in patients with T1D was significantly higher than in the control group (14% vs. 2.8%; p < 10−5). ATA were significantly more frequent in adult patients with T1D than in the blood donor group (20% vs. 1.6%; p < 10−8). The frequency of ATA in adult patients was significantly higher than in pediatric patients (20% vs. 9%; p = 0.006). The frequency of TPO-Ab and TG-Ab was significantly higher in patients with T1D than in the control group (13.5% vs. 2%; p < 10−8 and 7% vs. 2.2%, p = 0.008), respectively. Out of 312 patients with T1D, only one had TSHR-Ab. The simultaneous presence of three autoantibodies was found in one patient with T1D. Conclusion. ATA were frequent in patients with T1D. Serological screening of autoimmune thyroid disease is suggested in patients with T1D.