Coeliac disease in Iraqi type 1 diabetic patients

Background and study aimsHigh prevalence rates of coeliac disease (CD) in patients with type 1 diabetes mellitus (T1DM) have been reported. The aim of this study was to evaluate the frequency of silent CD in a sample of Iraqi patients with T1DM.Patients and methodsThis is a cross-sectional study done in Baghdad Teaching Hospital, Baghdad Medical City, Baghdad, Iraq, on 62 patients with T1DM. For all patients, immunoglobulin A (IgA) anti-tissue transglutaminase antibodies (IgA tTG), IgG anti-tissue transglutaminase antibodies (IgG tTG), IgA endomysial antibody (IgA EMA), IgA antigliadin antibodies (IgA AGA) and IgG antigliadin antibodies (IgG AGA) tests were done, with duodenoscopy, and at least four biopsies were taken from the second part of the duodenum.ResultsA total of 27 patients (43.5%) had normal small-intestinal histopathology (Marsh 0), one of them had a positive result for all serological markers used in the study, and another patient was positive for IgA tTG only. Ten patients (16.1%) had Marsh grade I, one of them was positive for IgA tTG, IgG tTG and IgA EMA, another patient was IgA deficient and had positive IgG tTG only and another patient with Marsh I had positive IgA tTG and IgG tTG only. Two patients (3.2%) had Marsh IIIA; three patients (4.8%) had Marsh IIIB histopathology, two of them were positive for all tests and one had positive IgA tTG and IgA EMA only. Two patients (3.2%) had Marsh IIIC histopathological features; they were positive for all serological tests, hence, the frequency of CD was 11.2%.ConclusionThe frequency of silent CD in Iraqi patients with T1DM is not rare, reaching up to 11.2%. Both EMA and tTG antibodies are useful as screening tests.     

Antibodies against human tissue transglutaminase and endomysium in diagnosing and monitoring coeliac disease

BACKGROUND: Coeliac disease (CD) patients often present a variety of uncharacteristic symptoms and therefore sensitive and specific screening tests are needed as an aid in making an accurate diagnosis. A recently developed ELISA, using human recombinant tissue transglutaminase (tTG) as antigen, was evaluated for its significance in the diagnosis of CD. The patient's compliance to a gluten-free diet and the serological reaction during gluten challenge were also monitored. The results were compared with IgA-endomysium antibody (EMA) results. METHODS: Sera previously collected from 365 patients (0.4-76 years) with jejunal biopsy on a gluten-containing diet and from 41 patients on a gluten-free diet or challenge were tested for IgA anti-human tTG antibodies (IgA tTG ab) with Celikey (Pharmacia Diagnostics). The study population comprised 208 CD patients and 157 controls. The diagnostic performance and cut-off for the assay were estimated with ROC analysis. EMA was analysed by indirect immunofluorescence microscopy on cryostat sections of monkey oesophagus. RESULTS: 200/208 patients with CD had positive IgA tTG ab (median >100 U/ml), while only 1/157 of the control patients were positive (median 1.67 U/ml). The area under the ROC curve was 98.3% and the sensitivity and specificity of the test were 96% and 99% for the study population. Only 4/365 patients (1%) presented discordant IgA tTG ab and EMA results, 2 of them had only IgA tTG ab and 2 only EMA. The IgA tTG ab levels and the EMA titres were closely correlated to the duration of gluten-free diet and gluten challenge, respectively. CONCLUSION: IgA tTG ab can be used as an accurate observer-independent alternative to EMA in diagnosing or monitoring CD.     

The frequency of the celiac disease among children with familial Mediterranean fever

We aimed to assess the frequency of celiac disease (CD) in patients with Familial Mediterranean Fever (FMF). This prospective study was carried out from October 2015 to March 2016 and included 303 patients with FMF. We used 98 sex- and age-matched healthy subjects as a control group. Levels of total IgA and tissue transglutaminase (tTG) IgA antibody were measured in all groups. Those with increased level of tTG IgA were tested for anti-endomysium IgA antibodies (EMA). Patients with positive EMA underwent gastro-duodenoscopy and intestinal biopsy for a definite diagnosis of CD. Only 9 of 303 patients (2.9%) were positive for tTG IgA. Patients positive for tTG IgA were then tested for EMA and only one of them (0.3%) had a positive result. This patient underwent gastro-duodenoscopy. The pathological report was compatible with Marsh 0 classification score for the diagnosis of CD. Two subjects from the control group were positive for tTG IgA but none of them had positive EMA antibodies. We did not find CD in the large cohort of childhood FMF patients. The prevalence of CD did not show association with presence of childhood FMF in this study and CD would not be a considerable complication of childhood FMF.     

Antibodies Against Human Tissue Transglutaminase and Endomysium in Diagnosing and Monitoring Coeliac Disease

Background: Coeliac disease (CD) patients often present a variety of uncharacteristic symptoms and therefore sensitive and specific screening tests are needed as an aid in making an accurate diagnosis. A recently developed ELISA, using human recombinant tissue transglutaminase (tTG) as antigen, was evaluated for its significance in the diagnosis of CD. The patient's compliance to a gluten-free diet and the serological reaction during gluten challenge were also monitored. The results were compared with IgA-endomysium antibody (EMA) results. Methods: Sera previously collected from 365 patients (0.4-76 years) with jejunal biopsy on a gluten-containing diet and from 41 patients on a gluten-free diet or challenge were tested for IgA anti-human tTG antibodies (IgA tTG ab) with Celikey ® (Pharmacia Diagnostics). The study population comprised 208 CD patients and 157 controls. The diagnostic performance and cut-off for the assay were estimated with ROC analysis. EMA was analysed by indirect immunofluorescence microscopy on cryostat sections of monkey oesophagus. Results: 200/208 patients with CD had positive IgA tTG ab (median >100 U/ml), while only 1/157 of the control patients were positive (median 1.67 U/ml). The area under the ROC curve was 98.3% and the sensitivity and specificity of the test were 96% and 99% for the study population. Only 4/365 patients (1%) presented discordant IgA tTG ab and EMA results, 2 of them had only IgA tTG ab and 2 only EMA. The IgA tTG ab levels and the EMA titres were closely correlated to the duration of gluten-free diet and gluten challenge, respectively. Conclusion: IgA tTG ab can be used as an accurate observer-independent alternative to EMA in diagnosing or monitoring CD.     

Screening for celiac disease in Down＇s syndrome patients revealed cases of subtotal villous atrophy without typical for celiac disease HLA-DQ and tissue transglutaminase antibodies

AIM: To investigate the prevalence of celiac disease (CD) as well as CD marker antibodies and susceptibility HLA-DQ haplotypes in 134 karyotyped Down's syndrome (DS) patients. METHODS: Immunoglobulin A (IgA) and G (IgG) type anti-gliadin antibodies (AGA), IgA type anti-tissue transglutaminase (tTG) antibodies (anti-tTG) with antigen of guinea pig and human source were determined by enzyme-linked immunosorbent assay and endomysium antibodies (EMA) by indirect immunofluoresence test. HLA-DQA1*0501/DQB1*0201 (DQ2) was revealed by polymerase chain reaction. Celiac disease was diagnosed by revised ESPGHAN criteria. RESULTS: 41% of DS patients had AGA, 6.0% IgA anti-tTG with guinea pig antigen, and 3.0 % IgA EMA (all positive for anti-tTG with human tTG). Subtotal villous atrophy was found in 5 out of 9 DS patients who had agreed to small bowel biopsy. One of them had DQA1*0501/DQB1*0201 and anti-tTG and EMA i.e. typical for CD markers (this case also fulfilled the ESPGHAN diagnostic criteria), but other four lacked these markers. Three non-biopsied DS patients had also most probably CD because DQA1*0501/DQB1*0201 and IgA anti-tTG (EMA) were detected. Thus, the prevalence of CD among our DS patients population is 3.0 % (95 % of confidence interval [CI]: 0.1-5.9 %). CONCLUSION: We confirm the increased frequency of CD among DS patients. In addition, we have revealed a subgroup of patients with subtotal villous atrophy but without characteristic for CD immunological and genetic markers. Whether these cases represent CD (with atypical immunopathogenesis) or some other immune enteropathy, requires further investigations.     

Is there an association between familial Mediterranean fever and celiac disease?

Familial Mediterranean fever (FMF) and celiac disease (CD) shares some clinical features such as abdominal pain, diarrhea, arthralgia, and arthritis. Furthermore, both diseases are related to several inflammatory disorders. Based on these analogies, we have investigated whether there is any relationship between CD and FMF. The study had two groups. Group I: 50 children with FMF were questioned and examined for the evidence of CD, serum immunoglobulin A (IgA) levels, antigliadin antibodies (AGA) IgA, AGA IgG, and anti-endomysial antibodies (EMA) IgA were tested, and intestinal biopsy was performed when necessary. Group II: 17 children with CD were evaluated for the presence of clinical and laboratory features of FMF and mutation analysis for MEFV gene was performed to all of them. Six predominant mutations (p.M694V, p.M680I, p.M694I, p.V726A, p.K695R, p.E148Q) in the MEFV gene were studied. The results were as follows-group I: three patients had diarrhea, six had abdominal pain, one had positive AGA IgA, six had AGA IgG, and one had EMA IgA. Intestinal biopsy was performed in one patient who was normal, so none of the patients with FMF were diagnosed as CD and group II: none of the patients with CD had complaints consistent with FMF. Four of the 17 patients (23.5%) were found to carry MEFV mutations. Three of them had heterozygous p.E148Q mutation and one of them had heterozygous p.M680I mutation. None of the FMF patients had CD. MEFV mutation frequency in patients with CD was similar to the normal population in Turkey. Our study did not reveal any association between CD and FMF.     

Anti-endomysial Antibody Negative Celiac Disease

Anti-endomysium antibodies (AEM) fail to identify all untreated celiac disease (CD) patients. This study aims to determine if additional serology, in particular, IgA anti-tissue transglutaminase (tTG) antibodies, increases detection. Fifty-three biopsy-proven untreated CD patients (39 women, 14 men; median age 51 years) and 65 control patients with normal duodenal histology (46 women, 19 men; age range 17–90 years, median 45 years) were prospectively studied. Serum total IgA, IgA anti-tTG, IgA AEM, IgA anti-gliadin (AGA) and IgG AGA antibodies were measured. Thirteen (25%) CD patients were AEM negative. None were IgA deficient. Three AEM-negative CD patients had a raised IgA anti-tTG and IgA AGA. IgG AGA was raised in 10 AEM-negative CD patients, but also in 14/65 (22%) of controls. In conclusion, AEM-negative CD is common and detection is only modestly enhanced by testing for IgA anti-tTG antibodies. Duodenal biopsy is still recommended for the accurate diagnosis of CD.     

Anti-transglutaminase IgA ELISA: clinical potential and drawbacks in celiac disease diagnosis

BACKGROUND: Since the identification of tissue transglutaminase (tTG) as the antigen for the anti-endomysial antibodies (EMA), several antigen-specific immunoassays have been reported for celiac disease (CD) screening. A first objective was to evaluate the suitability for CD screening of three different IgA tTG ELISAs, two of them based on guinea pig liver tTG (gp-tTG) (an in-house ELISA with a partially purified extract and a commercial ELISA with purified gp-tTG antigen) and a third recombinant human tTG (rh-tTG) ELISA. The results are compared with EMA and with the final clinical diagnosis. A second objective was to analyze antibody reactivities in those patients with anti-tTG and EMA discrepancies. METHODS: ELISA and EMA tests were used to measure IgA anti-tTG levels in sera from 259 patients (107 had CD and 72 had Type I diabetes mellitus). RESULTS: The purified gp-tTG ELISA was highly sensitive (97.7%) and specific (98.8%) in the detection of CD, almost equaling EMA. Rh-tTG ELISA did not improved the sensitivity of EMA, but its specificity was slightly superior. Immunoblot analysis with partially purified gp-tTG extract, the antigen most frequently used for anti-tTG detection, showed that the majority of false positives were due to IgA reactivities to contaminant proteins present in the liver antigenic extract. This low specificity was particularly problematic in diabetics. CONCLUSION: Purified tTG ELISAs, either with purified guinea pig liver or recombinant human antigens, can be used as quantitative and observer-independent alternatives to the traditional and time-consuming EMA in the screening of CD.     

Anti-transglutaminase IgA ELISA: Clinical Potential and Drawbacks in Celiac Disease Diagnosis

Background: Since the identification of tissue transglutaminase (tTG) as the antigen for the antiendomysial antibodies (EMA), several antigen-specific immunoassays have been reported for celiac disease (CD) screening. A first objective was to evaluate the suitability for CD screening of three different IgA tTG ELISAs, two of them based on guinea pig liver tTG (gp-tTG) (an in-house ELISA with a partially purified extract and a commercial ELISA with purified gp-tTG antigen) and a third recombinant human tTG (rh-tTG) ELISA. The results are compared with EMA and with the final clinical diagnosis. A second objective was to analyze antibody reactivities in those patients with anti-tTG and EMA discrepancies. Methods: ELISA and EMA tests were used to measure IgA anti-tTG levels in sera from 259 patients (107 had CD and 72 had Type I diabetes mellitus). Results: The purified gp-tTG ELISA was highly sensitive (97.7%) and specific (98.8%) in the detection of CD, almost equaling EMA. Rh-tTG ELISA did not improved the sensitivity of EMA, but its specificity was slightly superior. Immunoblot analysis with partially purified gp-tTG extract, the antigen most frequently used for anti-tTG detection, showed that the majority of false positives were due to IgA reactivities to contaminant proteins present in the liver antigenic extract. This low specificity was particularly problematic in diabetics. Conclusion: Purified tTG ELISAs, either with purified guinea pig liver or recombinant human antigens, can be used as quantitative and observer-independent alternatives to the traditional and time-consuming EMA in the screening of CD.     

Thyroid and celiac diseases autoantibodies in patients with adult chronic idiopathic thrombocytopenic purpura

The association of chronic idiopathic thrombocytopenic purpura (cITP) and thyroid autoimmune diseases (TAD) is a known but an uncommon condition. Celiac disease (CD), which is characterized by malabsorption and villous atrophy that occur as a consequence of the ingestion of wheat gluten may also be related to other autoimmune disorders. In this study, we investigated the prevalence of thyroid anti-microsomal (TAMA) and anti-thyroglobulin (TATA) auto antibodies, anti-gliadin (AGA) IgG, IgA, anti-endomisium (EMA) IgG and IgA antibodies in 74 patients with cITP and in 162 healthy controls. TATA positivity was found in 29, and TAMA positivity in 19 out of 74 patients; and in 16 and 18 out of 162 controls respectively (p < 0.0001 and p = 0.005, respectively). TAD was diagnosed in 29 of cITP patients. AGA IgG positivity was found in 17, and IgA was present in five out of 74 patients; and AGA IgG was found in 19, and IgA was detected in 4 out of 162 controls (p = 0.032 and p = 0.143, respectively). EMA IgG positivity was found in six out of 74 patients and in nine out of 162 control subjects (p = 0.566). EMA IgA positivity was found in two out of 74 patients and in one out of 162 controls (p = 0.232). We showed that the prevalence of TAD and related autoantibodies are higher in patients with cITP. We suggest that, patients with cITP should be followed up for development of TAD. In addition, all CD related auto antibodies were found to be more frequent in patients with cITP, but only the AGA IgG reached to the clinical significance. None of the CD related auto antibody positive patients developed clinically manifested CD. Large-scale designed studies are needed to clarify the long-term impact and importance of these CD related auto antibodies in patients with cITP.     

Serological screening for coeliac disease in patients with juvenile idiopathic arthritis

Background and study aimsJuvenile idiopathic arthritis (JIA) is characterized by autoimmune aetiology. A gene locus 4q27 related to rheumatoid arthritis, psoriatic arthritis, and coeliac disease is associated with susceptibility to JIA. There are reports indicating several patients with JIA had been diagnosed with CD. We aimed to assess the frequency of coeliac disease (CD) in patients with juvenile idiopathic arthritis (JIA).Patients and methodsThis prospective study was carried out from October 2015 to August 2016 and included 96 patients with JIA. All patients were evaluated in terms of clinical and laboratory findings of CD. Levels of total IgA and tissue transglutaminase antibody (tTG) IgA were measured in all patients. Those with increased level of tTG IgA were further tested for anti-endomysium IgA antibodies (EMA). Gastroduodenoscopy were planned for a definite diagnosis of CD in patients with positive EMA.ResultsOf the 96 patients in our study, 34 (35.4%) had oligoarticular form of JIA, 29 (30.2%) had polyarticular form, 12 (12.5%) had ERA form, 11 (11.5%) had systemic form, and 10 (10.4%) had psoriatic form. Sixteen of our patients (16.6%) were not using any drugs during the study. Neither EMA IgA antibodies were analysed nor gastro-duodenoscopy was performed because no patients were positive for tTG IgA. There was no difference in terms of tTG levels between the patients using NSAIDs or other drugs.ConclusionWe did not find CD in children with JIA. Long term studies with more JIA patients are needed to provide more precise interpretation.     

Population screening for coeliac disease in a low prevalence area in Italy

OBJECTIVE: A screening program was proposed for the village of Carcare (population 5700), located in a region of Italy with an apparently low prevalence of coeliac disease (CD): only 1 patient diagnosed out of 2557 inhabitants. The study group comprised 1002 individuals (568 F, 434 M, age range 13-90 years) recruited from blood donors, secondary school pupils and people referred to the local outpatient facilities for routine blood chemistry. MATERIAL AND METHODS: Total IgA, IgA anti-tissue transglutaminase (tTG) (ELISA, recombinant human antigen) and IgA antiendomysium (EMA) (IFI, umbilical cord substrate) antibodies were measured in the serum of all participants. All patients with IgA deficiency were investigated for IgG tTG antibodies, and in the case of disagreement between tTG and EMA, they were typed for HLA DQ2-DQ8 haplotypes. RESULTS: Thirteen subjects were positive and 988 negative for autoantibodies (3/988 had IgA deficiency). One serum sample was positive for tTG antibodies but negative for EMA. Ten out of 13 positive subjects consented to undergo duodenal biopsy, which invariably produced evidence of CD despite the absence of clinical signs/symptoms. A post-diagnostic clinical investigation provided evidence showing mild iron deficiency (4 subjects) and osteoporosis (2 subjects). After counselling, all subjects accepted a gluten-free diet. CONCLUSIONS: The prevalence of CD in the study group was 1:100 (1.0%; 95% CI: 0.5-1.8%): this indicates that CD is largely underdiagnosed in Carcare. Our results suggest that the low prevalence of CD observed in some regions is likely to be due to underdiagnosis.     

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.     

Accuracy of testing for antibodies to synthetic gliadin-related peptides in celiac disease.

BACKGROUND & AIMS: Our aim was to explore the diagnostic value of a newly developed synthetic peptide antibody assay addressing specific synthetic gliadin-derived deamidated peptides (AGA II) for the diagnosis of celiac disease (CD). METHODS: We assayed serum samples obtained prospectively at diagnosis from a population of 92 consecutive adult patients with CD and 113 non-CD controls. Patients were reevaluated after 6 months (n = 56) and 1 year (n = 20) of treatment. All patients and controls underwent intestinal biopsy and a set of CD-related serology tests. A newly developed enzyme-linked immunosorbent assay (ELISA) for detecting IgA and IgG antibodies against synthetic deamidated gliadin epitopes was used. RESULTS: At diagnosis, sensitivity and specificity were 94.6% and 99.1% for AGA II IgA and 92.4% and 100% for AGA II IgG. Absolute values and the proportion of positive samples for both antibodies were significantly reduced at 6 months (P < .0000) and 1 year (P < .001) after initiation of a gluten-free diet. Compared with conventional AGA, the peptide antibodies had greater sensitivity, specificity, positive and negative predictive values, accuracy, and likelihood ratios. Compared with antitissue transglutaminase antibodies, AGA II had similar sensitivity but greater specificity and predictive values, better likelihood ratios, and an excellent agreement (kappa statistic = .92). CONCLUSIONS: This study assessed the value of an ELISA assay in detecting antibodies to gliadin-related peptides. This assay appears to be a reliable tool for diagnosing CD and suggests promising accuracy that may be very useful in clinical practice.     

Should stored serum of patients previously tested for celiac disease serology be retested for transglutaminase antibodies?

INTRODUCTION: Tissue transglutaminase (tTG) antibodies are currently recognized as a highly sensitive indicator of celiac disease (CD). Although a high concordance rate between tTG antibodies and anti-endomysial antibodies (EMA) has been reported up to a third of known CD patients are positive for only one of these antibodies. AIM: To determine whether in laboratories in which serum samples previously examined for CD serology markers had not been discarded, these samples should be tested for tTG antibodies. METHODS: Fifty-eight stored (frozen at -70) serum samples of patients previously found to be EMA-negative but positive for one or more of the non-EMA markers: antigliadin antibodies (AGA)-IgA, AGA-IgG, antireticulin antibodies, were tested for anti-tTG antibodies (IMMCO Diagnostics). In patients found to be tTG positive, medical charts were reviewed and patients or their physicians contacted. RESULTS: Twelve of fifty-eight (20.7%) samples were found to be anti-tTG positive. These included: group A: 3/3 samples previously positive for AGA-IgA, AGA-IgG, and antireticulin antibodies. Group B: 3/16 samples positive for AGA-IgA and AGA-IgG. Group C: 3/4 samples positive for AGA-IgA and group D: 3/35 samples positive for AGA-IgG. Of the 12 positive patients, 1 was a 2-year-old boy, 5 were lost to follow up, and 7 underwent an intestinal biopsy. In 3 of these 7 patients, the biopsy was compatible with CD; 2 of these 3 patients were from group A and 1 from group B. CONCLUSIONS: In laboratories where stored serum samples are available, EMA-negative samples previously found to be positive for at least 2 other CD markers should be retested for tTG antibodies.     

Antibody levels in adult patients with coeliac disease during gluten-free diet: a rapid initial decrease of clinical importance

OBJECTIVE: Analysis of antibodies against tissue transglutaminase (tTG) has been shown valuable in the diagnosis of coeliac disease (CD) but how quickly serum titres decrease after introduction of a gluten-free diet (GFD) is not known in adults. CD is a well-recognized disorder amongst the general population and many persons try a GFD for fairly vague symptoms before they seek medical advice. Therefore, it is important to determine the time that the serologic tests remain predictive of the disease after the introduction of a GFD. METHODS: Sera were taken from 22 consecutively biopsy-proven adult patients with CD in connection with the diagnostic biopsy. The patients were followed for 1 year and sera were taken after 1, 3, 6 and 12 months after start of a GFD. Sera were stored at -20 degrees C and analysed for IgA antibodies against gliadin, endomysium and two different commercial tTG assays based on recombinant human tTG (tTGrh) and guinea-pig liver (tTGgp). RESULTS: Twenty patients could be followed during GFD and all antibody titres fell sharply within 1 month after introduction of a GFD and continued to decline during the survey interval. Thirty days after beginning the diet only 58, 84, 74 and 53% of all patients had positive antibody levels of tTGrh, tTGgp, EmA and AGA respectively. CONCLUSIONS: As the antibodies used to confirm the diagnosis of CD fall rapidly and continue to decline following the introduction of a GFD, it is important that health care providers carefully inquire about the possibility of self-prescribed diets before patients sought medical attention.     

Population screening for coeliac disease in a low prevalence area in Italy

Objective. A screening program was proposed for the village of Carcare (population 5700), located in a region of Italy with an apparently low prevalence of coeliac disease (CD): only 1 patient diagnosed out of 2557 inhabitants. The study group comprised 1002 individuals (568?F, 434?M, age range 13–90 years) recruited from blood donors, secondary school pupils and people referred to the local outpatient facilities for routine blood chemistry. Material and methods. Total IgA, IgA anti-tissue transglutaminase (tTG) (ELISA, recombinant human antigen) and IgA antiendomysium (EMA) (IFI, umbilical cord substrate) antibodies were measured in the serum of all participants. All patients with IgA deficiency were investigated for IgG tTG antibodies, and in the case of disagreement between tTG and EMA, they were typed for HLA DQ2-DQ8 haplotypes. Results. Thirteen subjects were positive and 988 negative for autoantibodies (3/988 had IgA deficiency). One serum sample was positive for tTG antibodies but negative for EMA. Ten out of 13 positive subjects consented to undergo duodenal biopsy, which invariably produced evidence of CD despite the absence of clinical signs/symptoms. A post-diagnostic clinical investigation provided evidence showing mild iron deficiency (4 subjects) and osteoporosis (2 subjects). After counselling, all subjects accepted a gluten-free diet. Conclusions. The prevalence of CD in the study group was 1:100 (1.0%; 95% CI: 0.5–1.8%): this indicates that CD is largely underdiagnosed in Carcare. Our results suggest that the low prevalence of CD observed in some regions is likely to be due to underdiagnosis.     

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.     

An algorithm for family screening for coeliac disease

INTRODUCTION Coeliac disease (CD) is a disorder in which geneticallypredisposed individuals develop a small intestinal enteropathy on exposure to dietary gluten. The small bowel abnormalities are reversed on withdrawal of gluten from the diet. Recent popu…     

Screening of Tissue Transglutaminase Antibody in Healthy Blood Donors for Celiac Disease Screening in the Turkish Population

Celiac disease (CD) is a disease having the characteristic pathology of the mucosa of the small intestine. The prevalence of CD in the Turkish population has not been investigated previously. The present study was designed to determine the prevalence of CD in healthy blood donors. Serum samples of 2000 healthy blood donors presenting to Hacettepe University Faculty of Medicine Hospital Blood Bank were tested for tissue transglutaminase (tTG) IgA and IgG antibodies with enzyme-linked immunosorbent assay (ELISA; Euroimmune, Germany). The histopathological findings for the cases with positive serology were evaluated. The distribution of sex was 95.7% male, and 4.3% female. The mean age was 33 +/- 9. Among 2000 donors, 23 (1.15%) were positive for tTG IgA antibody and 3 (0.15%) were positive for tTG IgG antibody. None of the samples was positive for both antibodies. Serum total IgA was measured in two cases with only tTG IgG positivity and was found to be low in one case. Twelve subjects positive for tTG agreed to endoscopy and biopsy. Histopathological examination revealed changes classified as Marsh III-II in one, Marsh II in two, Marsh I in seven, and Marsh 0 in two donors. This was the first study conducted to determine the prevalence of tTG positivity in the Turkish population. The tTG antibody positivity prevalence in healthy blood donors was as high as 1.3%. This study shows that the prevalence of CD in the Turkish population is relatively high in comparison to that in the Western world.