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

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

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.     

Anti-tissue transglutaminase antibodies in patients with abnormal liver tests: is it always coeliac disease?

BACKGROUND: Coeliac disease (CD) is found in 5-10% of patients with chronically abnormal liver tests and no obvious cause of liver disease. In this population the efficacy of screening for CD by anti-tissue transglutaminase (anti-tTG) may be impaired by the high rate of positive anti-tTG found in chronic liver disease. AIMS: To evaluate the prevalence of coeliac disease and the role of anti-tTG in patients with non-viral, non-autoimmune chronic and no obvious cause of liver damage. METHODS: Out of 2,512 consecutive patients with abnormal liver tests, 168 (118 men, 50 women; mean age 40.7 +/- 12.6 years) were defined, on the basis of clinical data and liver biopsy, as NAFLD or cryptogenic chronic hepatitis. All were tested by recombinant IgA and IgG anti-tissue transglutaminase. Patients with a positive serology underwent endoscopy with duodenal biopsies. RESULTS: NAFLD was diagnosed in 121 patients, in 6 associated with cirrhosis, while 47 patients were considered as cryptogenic hepatitis in the absence of steatosis. Anti-tTG were positive in 20/168 patients (3 IgA alone; 11 IgG alone; 6 both IgA and IgG). Coeliac disease was found at endoscopy and confirmed by histopathology only in the 6 patients (3.6%) with both IgA and IgG anti-tTG positivity. Four of the patients with CD had NAFLD (3.3%), in 2 of them associated with cirrhosis; while 2 of those with cryptogenic hepatitis (4.2%) had CD. CONCLUSIONS: The prevalence of CD in patients with chronically abnormal liver tests of unexplained etiology is 4%, with no relation with the degree of liver steatosis. Screening should be done by testing for IgA and IgG antibodies and then evaluating by endoscopy and biopsy only patients positive for both.     

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.     

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.     

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.     

IgA and IgG tissue transglutaminase antibodies in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) and coeliac disease (CD) are diseases of an autoimmune origin that share the human leukocyte HLA-B8 and HLA-DR3 histocompatibility antigens, yet the co-association of CD with SLE is mainly based on case reports. Thus, the real prevalence of CD in SLE is unclear. The aim of this study was to determine the prevalence of antitissue transglutaminase (anti-tTG) in SLE and the relation between SLE and CD. In this case-control study, 100 patients with SLE, and 120 healthy subjects were studied. Sera from all participants were analysed for the presence of IgA and IgG anti-tTG antibodies using a human recombinant tissue transglutaminase (tTG) immuno-enzymatic assay. Anti-tTG positive patients and controls were further tested for antiendomysial (EMA) antibodies by an indirect immunofluorescence and HLA typing (DQalpha1*0501-DQbeta1*0201 allele determination). Subjects who had EMA or the mentioned allele, underwent duodenal biopsy to confirm a possible diagnosis of CD. Anti-tTG antibodies (IgA or IgG isotypes) were found in three of the 100 SLE patients (overall prevalence of 3%): one had the IgA and two the IgG isotypes. Only 1 of 120 healthy subjects (0.8%) had a low positive reaction for IgA anti-tTG. Only the IgA anti-tTG positive SLE patient was diagnosed as having CD based on a positive IgA-EMA and small bowel biopsy findings. The two IgG anti-tTG positive SLE patients and the IgA anti-tTG positive healthy subject were classified as false positives (EMA negative and HLA DQalpha1*0501-DQbeta1*0201 allele negative). In conclusion, anti-tTG antibodies were found at a low rate in SLE patients and mostly did not indicate the presence of CD. Thus, serological screening for CD is not recommended in SLE, unless a clinical suspicion of CD is present.     

Effectiveness of the sorbitol H2 breath test in detecting histological damage among relatives of coeliacs

BACKGROUND: Small intestinal lesions have a wide severity in coeliac disease (CD), and early diagnosis is important in preventing neoplastic and non-neoplastic disorders related to CD. The aim of this study was to compare the effectiveness of the sorbitol H2 breath test (H2-BT) and serological tests (antigliadin (AGA), antiendomysium (EMA) and anti-tissue transglutaminase (anti-tTG)) as screening tests in the detection and estimation of CD prevalence in 1st-degree relatives. METHODS: Screening was performed in 111 1st-degree relatives of 37 coeliac families. Sorbitol H2-BT, AGA, EMA and anti-tTG antibodies were used to select the candidates for small-bowel biopsy. Relatives with abnormal serological tests and/or with sorbitol H2-BT positivity underwent a small-bowel biopsy. Small-bowel biopsy was also performed in relatives negative in all tests but with clinical complaints or suspected of having CD, and intestinal lesions were expressed according to the Marsh classification. RESULTS: CD was diagnosed in 49/111 screened relatives (44.14%): 5 showed Marsh IIIc, 8 Marsh IIIb, 16 Marsh IIIa, 13 Marsh II and 7 Marsh I lesions. Nineteen relatives showed the classical form of the disease, while the subclinical and silent forms were recorded in 20 and 10, respectively. AGA, EMA and anti-tTG showed strong positivity only in severe intestinal damage (Marsh IIIb-c lesions) (but overall positivity was 36.73%, 38.78% and 44.89% for AGA, EMA and anti-tTG, respectively), while sorbitol H2-BT showed strong positivity also in patients with slight histological damage (Marsh I-IIIa) (overall positivity was 83.67%). CONCLUSIONS: A significant proportion of coeliacs may be missed if relatives are screened by serology only, while the efficacy of sorbitol H2-BT in screening relatives is confirmed. This study confirms that neither a breath test nor serology can replace intestinal biopsy, which remains the gold standard for the diagnosis of CD.     

Effectiveness of the Sorbitol H 2 Breath Test in Detecting Histological Damage Among Relatives of Coeliacs

Background: Small intestinal lesions have a wide severity in coeliac disease (CD), and early diagnosis is important in preventing neoplastic and non-neoplastic disorders related to CD. The aim of this study was to compare the effectiveness of the sorbitol H 2 breath test (H2-BT) and serological tests (antigliadin (AGA), antiendomysium (EMA) and anti-tissue transglutaminase (anti-tTG)) as screening tests in the detection and estimation of CD prevalence in 1st-degree relatives. Methods: Screening was performed in 111 1st-degree relatives of 37 coeliac families. Sorbitol H2-BT, AGA, EMA and anti-tTG antibodies were used to select the candidates for small-bowel biopsy. Relatives with abnormal serological tests and/or with sorbitol H2-BT positivity underwent a small-bowel biopsy. Small-bowel biopsy was also performed in relatives negative in all tests but with clinical complaints or suspected of having CD, and intestinal lesions were expressed according to the Marsh classification. Results: CD was diagnosed in 49/111 screened relatives (44.14%): 5 showed Marsh IIIc, 8 Marsh IIIb, 16 Marsh IIIa, 13 Marsh II and 7 Marsh I lesions. Nineteen relatives showed the classical form of the disease, while the subclinical and silent forms were recorded in 20 and 10, respectively. AGA, EMA and anti-tTG showed strong positivity only in severe intestinal damage (Marsh IIIb-c lesions) (but overall positivity was 36.73%, 38.78% and 44.89% for AGA, EMA and anti-tTG, respectively), while sorbitol H2-BT showed strong positivity also in patients with slight histological damage (Marsh I-IIIa) (overall positivity was 83.67%). Conclusions: A significant proportion of coeliacs may be missed if relatives are screened by serology only, while the efficacy of sorbitol H2-BT in screening relatives is confirmed. This study confirms that neither a breath test nor serology can replace intestinal biopsy, which remains the gold standard for the diagnosis of CD.     

Screening of the adult population in Iran for coeliac disease: comparison of the tissue-transglutaminase antibody and anti-endomysial antibody tests

BACKGROUND AND AIMS: Population-based studies for the prevalence of coeliac disease (CD) in west-Asian countries are scarce. We aimed to determine the prevalence of gluten-sensitive enteropathy (GSE) in the general population of northern and southern Iran, and evaluate the sensitivity and specificity of the anti-endomysial antibody (EMA) immunofluorescent test and the enzyme-linked immunosorbent assay-based test for determination of the IgA anti-tissue transglutaminase antibody (tTG-Ab) using the human recombinant transglutaminase antigen for the detection of CD in screening the asymptomatic adult population. MATERIAL AND METHODS: Using a stratified random sampling method we enrolled a total of 2799 individuals (1438 from Sari and 1361 from Kerman). The mean age was 33.7 years (range 18-66), with 1398 men. IgA anti-tissue transglutaminase (tTG) and IgA anti-EMA were determined in the serum of all subjects. Those participants with a positive serology for any of the two tests underwent small intestinal biopsy, and were classified according to revised Marsh criteria histologically. A diagnosis of GSE was based on positive serology and a compatible histopathological finding. The maximum likelihood latent class model was used to estimate the sensitivity and specificity of the two tests. RESULTS: Twenty-nine cases showed positive IgA tTG-Ab (15 men and 14 women, mean age 35.4 years, range 18-59), whereas only five were simultaneously positive for EMA. Except for two subjects with normal small bowel histology (Marsh 0), all other subjects were found to have biopsy findings compatible with GSE: 18 Marsh I, five Marsh II, three Marsh IIIa and one Marsh IIIc lesions. he prevalence of GSE was 0.96% or 1:104. The sensitivity and specificity of the human-recombinant IgA tTG-Ab assay were 100 and 99%, respectively, whereas the results for IgA EMA were 19 and 100%, respectively. The IgA EMA was positive in cases with advanced mucosal lesions of the small bowel. The mean serum value of IgA tTG-Ab was higher in patients with severe enteropathy compared with those showing slight mucosal changes (P<0.05). CONCLUSION: The minimum prevalence of gluten sensitivity among the general population of northern and southern Iran is 1:104. The best screening test for the detection of GSE in the general population is IgA tTG-Ab.     

Elevation of IgG antibodies against tissue transglutaminase as a diagnostic tool for coeliac disease in selective IgA deficiency

BACKGROUND: IgA serum autoantibodies against tissue transglutaminase (tTG) have an established diagnostic value in coeliac disease, and high efficacy tests are widely available for their detection. However, serological evaluation of IgA deficient subjects is still difficult. AIMS: To evaluate the diagnostic potential of IgG class anti-tTG autoantibodies measured quantitatively using an enzyme linked immunosorbent assay (ELISA) compared with immunofluorescent detection of coeliac autoantibodies. PATIENTS: We tested serum samples from 325 IgA deficient subjects, including 78 patients with coeliac disease, 73 disease controls, and 174 blood donors. METHODS: IgG antibodies against human recombinant tTG were measured with an ELISA. IgG antiendomysium antibodies (EMA) were assayed by indirect immunofluorescence on human jejunum and appendix sections. RESULTS: The IgG anti-tTG ELISA had a sensitivity of 98.7% and a specificity of 98.6%, and the correlation with IgG EMA titres was high (r(s)=0.91). One coeliac patient, initially negative in all autoantibody tests, displayed both IgG anti-tTG antibodies and IgG EMA during later gluten exposure. IgG anti-tTG antibodies and EMA titres showed significant decreases (p<0.001) in treated patients. The frequency of IgG anti-tTG autoantibody positivity was 9.8% among IgA deficient blood donors and 11 of the 12 positive subjects with known HLA-DQ haplotypes carried DQ2 or DQ8 alleles. CONCLUSIONS: IgG anti-tTG and IgG EMA autoantibody tests are highly efficient in detecting coeliac disease in IgA deficient patients. The high prevalence of coeliac antibodies among symptom free IgA deficient blood donors who also carry coeliac-type HLA-DQ genes indicates that all IgA deficient persons should be evaluated for coeliac disease.     

In patients with dermatitis herpetiformis distribution of transglutaminase in cutaneous tissue does not differ from controls

BACKGROUND: Dermatitis herpetiformis may be regarded as the cutaneous counterpart of coeliac disease. These conditions are related to the ingestion of gluten and both are characterised by circulating antibodies against tissue transglutaminase. AIMS: To study the distribution of tissue transglutaminase in the skin of dermatitis herpetiformis patients and controls, and to investigate whether the dermal IgA deposits, diagnostic for dermatitis herpetiformis, are related to tissue transglutaminase expression in the skin. METHODS: A series of 11 patients with dermatitis herpetiformis had a 4 mm punch biopsy taken from the uninvolved perilesional skin. A group of 16 controls, undergoing surgical removal of benign nevi, gave perilesional skin. Biopsies were covered with OCT and frozen at -80 degrees C. After washing, skin biopsy sections were incubated with an IgG anti-tissue transglutaminase mouse monoclonal antibody. After washing, sections were incubated with anti-mouse IgG. RESULTS: The anti-tissue transglutaminase monoclonal antibody specifically recognised the basal epidermal cells. This staining was no different between patients and controls. CONCLUSION: Our results suggest that tissue transglutaminase can be recognised in the basal epidermal layer both of patients with dermatitis herpetiformis and controls. Since this distribution does not correspond to the distribution of dermal IgA deposits, it is concluded that dermatitis herpetiformis dermal IgA deposits are not due to antibodies directed against cutaneous tissue transglutaminase.     

The prevalence of unrecognized adult celiac disease in Central Anatolia

BACKGROUND: The aim of this study is to assess the prevalence of unrecognized adult celiac disease in Central Anatolia of Turkey and establish if prevalence figures are similar to other reports in the international literature. METHODS: Subjects were randomly selected from patients at the time of blood sampling because of a routine examination or suspicion of some disorder other than celiac diseases and were screened with anti-tissue transglutaminase IgA and serum IgA measurements. Duodenal biopsies were taken from the patients who were found positive for anti-tissue transglutaminase IgA and had low IgA levels. RESULTS: A total of 906 subjects between 20 and 59 years of age were included. Small bowel biopsies were performed for 55 of the 906 participants. Fifty-two of 55 participants taken biopsies had anti-tissue transglutaminase IgA levels greater than 15 IU/mL and 3 of them had low IgA levels. Celiac disease was diagnosed as 9 of 906 (0.99%). The majority of the patients with celiac disease had nonspecific gastrointestinal symptoms. There was no correlation between the titers of anti-tissue transglutaminase IgA and the severity of histopathologic findings. CONCLUSIONS: In this study, we found that unrecognized adult celiac disease in Central Anatolia affects approximately 1% of the population, and the major constellation of symptoms are nonspecific gastrointestinal related. Serologic data are not adequate for a definite diagnosis, but the anti-tissue transglutaminase IgA test has high diagnostic value and may be used as screening tool. Confirmation with intestinal biopsy is required for a definite diagnosis.     

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.     

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.     

Tissue transglutaminase antibodies in patients with end-stage heart failure

OBJECTIVE: For celiac disease (CD), screening a trend has recently emerged to measure tissue transglutaminase antibodies (tTGA) by immunoassays instead of the more laborious endomysial antibodies (EmA), as they recognize the same target, tissue transglutaminase (tTG). However, a high rate of false-positive results has been reported in some patient series with diseases known to be associated with CD. Moreover, tTG is a ubiquitous, multifunctional enzyme, overexpressed in experimental models of heart failure. Therefore, we assessed the specificity of tTGA assays in a large series of EmA-negative patients with end-stage heart failure. METHODS: We studied 288 patients with end-stage heart failure and 60 blood donors. No subject had clinical evidence of CD or IgA deficiency, and all were EmA negative. Serum IgA and IgG tTGA were measured by means of commercial kits using as substrate, either guinea pig or recombinant human tTG. Blocking studies and Western blots were also performed using recombinant human tTG. RESULTS: All blood donor sera were IgA tTGA negative. IgA tTGA positivity was observed in 47.6% and 49.1% of patients with heart failure using, respectively, guinea pig tTG and recombinant human tTG as substrates. Preincubation of positive sera with recombinant human tTG resulted in 81% blocking of IgA tTGA in immunoassay. Western blot analysis confirmed the presence of antibodies against recombinant human tTG. IgA tTGA-positive sera were also IgG tTGA positive. CONCLUSIONS: IgA and IgG tTGA occur in a large number of EmA-negative patients with end-stage heart failure, and their presence is unlikely to be caused by concomitant CD.     

The prevalence of celiac disease in patients fulfilling Rome III criteria for irritable bowel syndrome

Background and aimsCeliac disease shares several symptoms which constitute some of the ROME criteria used for the diagnosis of irritable bowel syndrome (IBS), and as such many patients with underlying Celiac disease may be mistakenly diagnosed as having IBS. The aim of the present study was to determine the prevalence of Celiac disease in patients with IBS fulfilling ROME III criteria.Materials and methodsPatients who fulfilled ROME III criteria for irritable bowel syndrome were screened for Celiac disease using the Biocard^TM Celiac Disease Stick test, and patients who tested positive had their serum samples analyzed for antigliadin IgA and IgG, and anti-tissue transglutaminase IgA antibodies. Patients with detectable antibody levels underwent endoscopic duodenal biopsy to confirm a diagnosis of Celiac disease.ResultsTwo of 100 patients who were diagnosed as having irritable bowel syndrome as per the Roma III criteria were found to have elevated levels of serum antigliadin IgA and IgG, and anti-tissue transglutaminase IgA antibodies, with histological evidence of Celiac disease on examination of duodenal biopsy. Both patients were started on a gluten-free diet, showing significant improvement in their symptoms on follow-up.ConclusionsCeliac disease is a common finding among patients labeled as IBS. Celiac disease must be considered in differential diagnosis of IBS especially in the therapy refractory group.     

Anti-transglutaminase antibodies and coeliac disease

Background: Anti-endomysial antibodies have high specificity for coeliac disease but measurements are limited by the requirement for monkey oesophagus, a substrate that is expensive, and of limited availability and ethical acceptance. Tissue transglutaminase has recently been identified as the endomysial autoantigen in coeliac disease.
Aims: To examine the validity of serum tissue transglutaminase antibody levels in patients with coeliac disease and to assess their sensitivity and specificity against standard serological tests.
Methods: Serum IgA anti-tissue transglutaminase antibody titres (measured by ELISA), IgA anti-gliadin antibody litres (measured by a commercial ELISA) and anti-endomysial antibody titres (measured by indirect immunofluorescence) were determined in 46 untreated and 14 treated patients biopsy-proven coeliac disease and 145 disease and healthy controls.
Results: All patients with untreated coeliac disease were positive for anti-endomysial and anti-tissue transglutaminase antibodies (sensitivity 100%). Seventy-one per cent of treated coeliac patients were anti-tissue transglutaminase antibody negative. Five of 145 disease and healthy controls had low titres of anti-tissue transglutaminase antibody (specificity 97%); no controls were anti-endomysial antibody positive.
Conclusions: Our results demonstrated the sensitivity and specificity of IgA anti-tissue transglutaminase antibodies to correlate highly with anti-endomysial antibodies in the diagnosis of coeliac disease. The ELISA for IgA anti-tissue transglutaminase antibodies is quantitative and easy to perform and is a valid alternative to indirect immunofluorescence for anti-endomysial antibodies in screening for suspected coeliac disease.     

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.     

Celiac disease in a group of children and adolescents with type 1 diabetes mellitus

To know the prevalence of celiac disease (CD) in a group of children and adolescents with type I diabetes mellitus. A cross sectional study was conducted at the Instituto Materno Infantil de Pernambuco (IMIP) in March 2000. The sample consisted of 19 children and adolescents with type I diabetes mellitus that had the human anti-tissue transglutaminase antibodies assessed using kits from the Eurospital Laboratory. In case of positive results it was realized small intestine biopsy to confirm the diagnosis. For the calculation of the prevalence of CD it was considered the number of patients with serum positive histological alterations of the mucous membrane of the small intestine compatible with CD. Four patients presented serum positivity for human anti-tissue transglutaminase antibodies with a serum prevalence of 21% (4/19). Out of these four subjects, three who accomplished small intestine biopsy presented histological alterations compatible with CD. The prevalence of CD in this group was 15.8% (3/19). The prevalence of CD in this study group was high, suggesting that those with type I diabetes mellitus should be led as a group of high risk to develop this disease.