A biopsy is not always necessary to diagnose celiac disease

Evaluation of Celiac Disease by Minimally Invasive Biomarkers in a Spanish Pediatric Population

Background: The diagnosis of celiac disease (CD) has been substantially improved with the availability of highly sensitive CD-specific IgA-TG2, Ig-GDP, and IgA-EMA. The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) published (2012) and updated (2020) diagnostic criteria for CD in order to simplify CD diagnosis and to avoid biopsies in selected patients. Methods: A prospective study including 5641 pediatric patients (0–16 years old) from January 2012 to January 2019 was performed. CD diagnosis was made according to the ESPGHAN algorithm. The objective of this study was to evaluate the utility of biomarkers and the relationship between TGA-IgA and EMA titers. Results: CD diagnoses were confirmed in 113 patients, 110 were IgA-TG2-positive and 3 (2.7%) had IgA deficiency. The diagnosis was made by serologic tests in 95 (84.1%) patients. Only 18 (15.9%) patients underwent intestinal biopsy. We obtained 100% concordance between IgA-EMA and positive results for IgA-TG2 ≥ 10 ULN with IgA-EMA antibody titer ≥ 1:80. Conclusions: This study provides evidence of a positive correlation between IgA-TG2 antibody serum levels and IgA-EMA. The diagnosis could be guaranteed with strict application of IgA-TG2 values ≥ 10 ULN (confirmed by subsequent testing) plus the serological response to the gluten-free diet (GFD).

Morphological evaluation of bulb and distal duodenal biopsies in pediatric celiac disease with clinical and serological correlation

Background and Aims

An early correct diagnosis of celiac disease (CD) is fundamental to reversal of symptoms and prevention of complications in pediatric patients. Our aim was to evaluate the role of duodenal bulb biopsy by studying the degree of mucosal damage in the duodenal bulb (D1) and second part of the duodenum (D2) and correlating the findings with serum IgA anti-tTG levels.

Settings and Design

Pediatric patients (age <18 years) with clinical suspicion of CD and positive IgA anti-tTG titers were consecutively enrolled over a period of one year. Demographic variables, anthropometry, clinical history, laboratory values and endoscopic findings were studied. Endoscopic biopsies obtained from D1 and D2 were evaluated and assigned histopathologic grades that were correlated with serology.

Statistical Analysis Used

Descriptive statistics were employed.

Results

A total of 37 clinically suspected cases of pediatric CD were studied. The mean age was 6.7 years and the M:F ratio was 1:1.3. Thirty-two (32) children had varying degrees of growth impairment. Eight (8) children had only extra-intestinal symptoms. Thirty (30) children were anemic, hypoalbuminemia was seen in five (5) children while transaminitis was seen in two (2) children. IgA anti-tTG >300 U/ml was associated with Marsh-Oberhuber Grade 3 morphology at atleast one site.

Conclusions

Low positive serology values should be confirmed by histopathology. Biopsies should be taken even in the absence of endoscopic abnormality. Additional D1 biopsies placed in a separate container can increase the diagnostic yield.

Automated Analyzers Are Suited for Diagnosing Celiac Disease Without a Biopsy

OBJECTIVES

The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) 2012 guidelines, enabled for the first time, a nonbiopsy approach in the diagnosis of celiac disease (CD). We aimed to prospectively assess 4 tissue-transglutaminase (tTg) IgA assays of 4 random-access analyzers and examine their accuracy in diagnosing CD without a biopsy.

METHODS

We enrolled 186 consecutive children referred to upper endoscopy and intestinal biopsy. One group included 109 patients with positive tTg that was referred for suspected CD. Another group included 77 patients with negative tTg referred because of other indications. All participants had a blood sample taken at the time of endoscopy. Samples were tested with 4 tTg IgA assays on automated analyzers and 1 Elisa kit. All intestinal biopsies were evaluated by a local pathologist, a central pathologist, and a CD expert blinded to each other. CD was diagnosed when full agreement was reached. Analytical performance of the assays included precision with controls and samples, lot to lot variation, and carryover.

RESULTS

In our cohort, all tested tTg IgA-automated assays showed sensitivities above 98% and specificities above 99%. ROC analysis demonstrated AUC (area under the curve) >0.99 for all 4 analyzers. The positive-predictive values (PPV) were all >0.99 and negative-predictive values (NPV) were >0.97. The Elisa kit had sensitivity of 95%, specificity of 96%, AUC of 0.96, PPV of 0.98 and NPV of 0.93.

CONCLUSION

CD can be accurately diagnosed without biopsy based on tTg IgA levels at least 10 times the ULN using the 4 high-volume random-access analyzers used in our study.

European Society Paediatric Gastroenterology, Hepatology and Nutrition Guidelines for Diagnosing Coeliac Disease 2020

OBJECTIVES

The ESPGHAN 2012 coeliac disease (CD) diagnostic guidelines aimed to guide physicians in accurately diagnosing CD and permit omission of duodenal biopsies in selected cases. Here, an updated and expanded evidence-based guideline is presented.

METHODS

Literature databases and other sources of information were searched for studies that could inform on 10 formulated questions on symptoms, serology, HLA genetics, and histopathology. Eligible articles were assessed using QUADAS2. GRADE provided a basis for statements and recommendations.

RESULTS

Various symptoms are suggested for case finding, with limited contribution to diagnostic accuracy. If CD is suspected, measurement of total serum IgA and IgA-antibodies against transglutaminase 2 (TGA-IgA) is superior to other combinations. We recommend against deamidated gliadin peptide antibodies (DGP-IgG/IgA) for initial testing. Only if total IgA is low/undetectable, an IgG-based test is indicated. Patients with positive results should be referred to a paediatric gastroenterologist/specialist. If TGA-IgA is ≥10 times the upper limit of normal (10× ULN) and the family agrees, the no-biopsy diagnosis may be applied, provided endomysial antibodies (EMA-IgA) will test positive in a second blood sample. HLA DQ2-/DQ8 determination and symptoms are not obligatory criteria. In children with positive TGA-IgA <10× ULN at least 4 biopsies from the distal duodenum and at least 1 from the bulb should be taken. Discordant results between TGA-IgA and histopathology may require re-evaluation of biopsies. Patients with no/mild histological changes (Marsh 0/I) but confirmed autoimmunity (TGA-IgA/EMA-IgA+) should be followed closely.

CONCLUSIONS

CD diagnosis can be accurately established with or without duodenal biopsies if given recommendations are followed.

HLA-DQ2/DQ8 frequency in adult patients with celiac disease, their first-degree relatives, and normal population in Turkey

BACKGROUND/AIMS

Celiac disease is an autoimmune, familial disease that results in susceptibility to gluten in cereal and cereal products in genetically susceptible individuals. The aim of the present study was to investigate the presence of HLA-DQ2/DQ8 in patients with celiac disease, their first-degree relatives, and healthy community.

MATERIALS AND METHODS

HLA-DQ2/DQ8 analysis was performed in adult patients with celiac disease >18 years old (94 patients), their first-degree relatives (89 people), and healthy group (102 individuals). Anemia, osteoporosis, and diarrhea were interrogated in the celiac patient group and also anti-tissue transglutaminase, anti-endomysium, and anti-gliadin antibodies were recorded.

RESULTS

There was a significant relationship between HLA-DQ2/DQ8 presence in all groups, and the distribution of HLA-DQ2/DQ8 in all groups was different (p=0.000). No statistically significant correlation was found between the HLA tissue groups and diarrhea (p=0.087), osteoporosis (p=0.215), anemia (p=1.000), tissue transglutaminase antibodies (p=0.295), anti-gliadin antibodies (p=0.104), and anti-endomysium antibodies (p=0.243) in the celiac patient group.

CONCLUSION

HLA-DQ2/DQ8 can be used to diagnose celiac disease particularly when the tests are useless and to screen first-degree relatives.

Influence of HLA on clinical and analytical features of pediatric celiac disease

Background

Celiac disease (CD) is triggered by gluten and related prolamines in genetically susceptible individuals. We aimed to investigate the influence of HLA-DQ genotypes in clinical, serological and histological features related to CD.

Methods

A retrospective observational study was performed including 463 Spanish patients with biopsy-proven CD. Clinical, serological, histological and HLA-DQ genetic data were collected from each participant. The presence of a family history of CD was also considered. Bivariate (chi-square tests or the Fisher’s exact test) and multivariate (logistic regression after adjusting for age and sex) analyses were performed to assess the association between clinical and laboratory parameters with HLA-DQ.

Results

A predominance of females (62%), classical clinical presentation (86%) and positive anti-transglutaminase 2/endomysium antibodies (99%) was observed in our sample, with a mean age at onset of 2.6 ± 0.1 years. Five percent of our patients were first-degree relatives of subjects with CD, with HLA-DQ genetics showing increased homozygosity of HLA-DQ2.5 (p = 0.03) and HLA-DQ8 (p = 0.09). In the non-CD family history group, an association between delayed disease onset and HLA-DQ8 carriage was observed (p < 0.001), besides an influence of HLA-DQB1*02 gene dosage on clinical presentation and severity of histological damage (after adjusting for age and sex, p = 0.05 and p = 0.02, respectively) and a trend towards presence of specific antibodies (p = 0.09). These associations could not be evaluated properly in the group of patients with affected first-degree relatives due to the small sample size.

Conclusions

HLA-DQ genotypic frequencies differ slightly between CD patients depending on their family history of CD. In patients lacking CD first-degree relatives, carriage of HLA-DQ2.5 with double dose of HLA-DQB1*02 seems to be associated with classical clinical presentation and more severe histological damage.

Can High Titres of Anti Tissue Transglutaminase Antibodies Reduce the Need for Intestinal Biopsy for Diagnosis of Celiac Disease?

Traditionally small intestinal biopsy has been considered a gold standard for the diagnosis of celiac disease (CD). But now data has shown that serological markers like anti-tissue-transglutaminase antibodies (tTGA) can be used to make the diagnosis with great sensitivity and specificity. The objective of the present study was to evaluate whether patients with high probability of CD and high titre of tTGA, have a high probability of intestinal damage and may not require biopsy for final diagnosis. All the cases with tTGA levels ≥15 IU/ml and who subsequently underwent biopsy from July 2010 to June 2013 were selected. Histopathological findings graded as per Marsh classification were correlated with serum tTGA levels. Grade 3 lesions were considered diagnostic for the disease. Out of total 731 patients 470 had serum tTGA levels >100 IU/ml and 261 patients had <100 IU/ml. Highest levels of tTGA (219.3 IU/ml) were seen in grade 3c which was >12 times the normal cutoff value. Mean serum tTGA in higher histological grade i.e. 3 (3a, 3b, 3c) was 186.7 IU/ml (>12 times the normal cut off value) as compared to grade 1 which was 108.9 IU/ml (>7 times the normal cut off value). Using a tTGA cutoff value of 70 IU/ml, sensitivity was found to be 83.9% while specificity was 56.10% with an overall accuracy of 77.7%. This study confirms that a small intestinal biopsy is not always necessary for the diagnosis of CD in symptomatic patients with high tTGA levels (>70 IU/ml).

Serum intestinal fatty acid-binding protein in the noninvasive diagnosis of celiac disease

Current diagnostic guidelines for celiac disease (CD) in pediatric patients require a duodenal biopsy if the IgA anti-tissue transglutaminase (tTG) is below 10x the upper limit of normal (ULN). Additional markers may enable a noninvasive diagnosis in this group. Serum intestinal-fatty acid-binding protein (I-FABP), a marker for intestinal epithelial damage, could be useful in this respect. A total of 95 children with a clinical suspicion of CD and tTG 1-10x ULN were investigated. All had a duodenal biopsy and analysis of serum I-FABP. A control group of 161 children with familial short stature and normal tTG was included. I-FABP levels in the 71 patients with tTG 1-10x ULN and biopsy-proven CD (median 725 pg/mL) were not significantly different (p = 0.13) from the levels in the 24 patients with a tTG 1-10x ULN but a normal biopsy (median 497 pg/mL). However, when combining tTG and I-FABP levels, 11/24 patients could have been diagnosed noninvasively if tTG is ≥ 50 U/mL and I-FABP ≥880 pg/mL or in 12/19 patients if tTG is ≥ 60 U/mL and I-FABP ≥ 620 pg/mL. Therefore, addition of I-FABP to the diagnostic procedure of CD may provide a noninvasive diagnosis in patients with a tTG ≥ 50 U/mL.

Accuracy in Diagnosis of Celiac Disease Without Biopsies in Clinical Practice

BACKGROUND & AIMS

The guidelines of the European Society of Pediatric Gastroenterology, Hepatology, and Nutrition allow for diagnosis of celiac disease without biopsies in children with symptoms and levels of immunoglobulin A against tissue-transglutaminase (TGA-IgA) 10-fold or more the upper limit of normal (ULN), confirmed by detection of endomysium antibodies (EMA) and positivity for HLA-DQ2/DQ8. We performed a large, international prospective study to validate this approach.

METHODS

We collected data from consecutive pediatric patients (18 years or younger) on a gluten-containing diet who tested positive for TGA-IgA from November 2011 through May 2014, seen at 33 pediatric gastroenterology units in 21 countries. Local centers recorded symptoms; measurements of total IgA, TGA, and EMA; and histopathology findings from duodenal biopsies. Children were considered to have malabsorption if they had chronic diarrhea, weight loss (or insufficient gain), growth failure, or anemia. We directly compared central findings from 16 antibody tests (8 for TGA-IgA, 1 for TGA-IgG, 6 for IgG against deamidated gliadin peptides, and 1 for EMA, from 5 different manufacturers), 2 HLA-DQ2/DQ8 tests from 2 manufacturers, and histopathology findings from the reference pathologist. Final diagnoses were based on local and central results. If all local and central results were concordant for celiac disease, cases were classified as proven celiac disease. Patients with only a low level of TGA-IgA (threefold or less the ULN) but no other results indicating celiac disease were classified as no celiac disease. Central histo-morphometry analyses were performed on all other biopsies and cases were carefully reviewed in a blinded manner. Inconclusive cases were regarded as not having celiac disease for calculation of diagnostic accuracy. The primary aim was to determine whether the nonbiopsy approach identifies children with celiac disease with a positive predictive value (PPV) above 99% in clinical practice. Secondary aims included comparing performance of different serological tests and to determine whether the suggested criteria can be simplified.

RESULTS

Of 803 children recruited for the study, 96 were excluded due to incomplete data, low level of IgA, or poor-quality biopsies. In the remaining 707 children (65.1% girls; median age, 6.2 years), 645 were diagnosed with celiac disease, 46 were found not to have celiac disease, and 16 had inconclusive results. Findings from local laboratories of TGA-IgA 10-fold or more the ULN, a positive result from the test for EMA, and any symptom identified children with celiac disease (n = 399) with a PPV of 99.75 (95% confidence interval [CI], 98.61-99.99); the PPV was 100.00 (95% CI, 98.68-100.00) when only malabsorption symptoms were used instead of any symptom (n = 278). Inclusion of HLA analyses did not increase accuracy. Findings from central laboratories differed greatly for patients with lower levels of antibodies, but when levels of TGA-IgA were 10-fold or more the ULN, PPVs ranged from 99.63 (95% CI, 98.67-99.96) to 100.00 (95% CI, 99.23-100.00).

CONCLUSIONS

Children can be accurately diagnosed with celiac disease without biopsy analysis. Diagnosis based on level of TGA-IgA 10-fold or more the ULN, a positive result from the EMA tests in a second blood sample, and the presence of at least 1 symptom could avoid risks and costs of endoscopy for more than half the children with celiac disease worldwide. HLA analysis is not required for accurate diagnosis. Clinical Trial Registration no: DRKS00003555.

Application of the Biopsy-Sparing ESPGHAN Guidelines for Celiac Disease Diagnosis in Adults: A Real-Life Study

BACKGROUND

Current adult celiac disease diagnosis requires histological confirmation. However, pediatric guidelines have proposed biopsy-sparing algorithms.

AIMS

To explore the applicability of the ESPGHAN criteria and assess the accuracy of serology in predicting disease in adults.

METHODS

We evaluated 234 consecutive adults showing elevated anti-tTG titers, EMA-positivity, and genetic susceptibility. Patients underwent upper endoscopy with duodenal biopsy. We determined optimal anti-tTG cutoff levels using ROC curves.

RESULTS

Mean anti-tTG levels were 71.1 ± 66.5 U/ml; mean normalized levels were 14.8 ± 14.1 × ULN (mean ± SD). Partial/total villous atrophy was present in 36%/55% of cases, respectively. Anti-tTG levels correlated with histology (r _s = 0.397, p < 0.001). AUC was similar before and after normalization (0.803 vs 0.807). Applying the ESPGHAN criterion (≥10 × ULN), we calculated a 97.66% PPV. ROC curve analysis showed an optimal cutoff of ≥16 × ULN, with a PPV of 98.86%. Eleven different assays were used for anti-tTG titer determination: Two were prevalent, labeled A (n = 141) and B (n = 59). They performed differently regarding disease prediction (AUC = 0.689 vs 0.925, p < 0.01), showing distinct optimal cutoff values (14.3 × ULN vs 3.7 × ULN), even after standardization (-0.14 vs -1.2).

CONCLUSION

In adult symptomatic patients showing EMA-positivity and genetic susceptibility, anti-tTG titers correlated with histology. ESPGHAN criteria performed similarly to previous studies. However, a calculated 16 × ULN cutoff showed an improved PPV. Among prevalent assays, PPV peaked differently both after normalization and standardization, indicating intrinsic differences in performance, thus preventing uniform prediction of disease in a real-life setting. Assay-specific optimal cutoffs seem possible, but would complicate diagnostic criteria. However, biopsy-sparing strategies in adults could prove useful in challenging patients.

Omitting duodenal biopsy in children with suspected celiac disease and extra-intestinal symptoms

BACKGROUND

The aim of our study is to evaluate if in children with highly positive serology and HLA-DQ2/DQ8 (triple test, TT) and only extra-intestinal symptoms, it is possible to omit performing an intestinal biopsy for celiac disease (CD) diagnosis, as suggested by the new European Society for Pediatric Gastroenterology, Hepatology and Nutrition ESPGHAN guidelines.

METHODS

In this retrospective study a total of 105 patients, suspected of having CD because of extra-intestinal symptoms and showing serum tissue transglutaminase antibody (anti-tTG) and anti-endomysial antibody (EMA) measurements and HLA genotyping, were considered for the final analysis (33 boys and 72 girls; age range 1.5-17.6 years).

RESULTS

Histological findings confirmed diagnosis of CD in 97 (92.4%) patients. Forty-one patients (39%) showed anti-tTG >10 times normal values, positive EMA and positive HLA-DQ2/DQ8 (positive TT). All of them had a diagnosis of CD, therefore there were no false positive cases. Sixty-four patients were negative for the TT. In eight cases, CD was ruled out and these were considered true negative cases. In the remaining 56 negative TT patients, intestinal biopsy confirmed CD diagnosis and they were considered false negatives. Based on these results, specificity for the TT was 100% and sensitivity was 42.3%.

CONCLUSIONS

On the basis of the present study, diagnosis of CD can be reliably performed without a duodenal biopsy in children with only extra-intestinal symptoms.

Correlation of Tissue Transglutaminase with Modified Marsh Grading in Celiac Disease: A Prospective Cohort Study

OBJECTIVE

To find out correlation between serum anti-tissue transglutaminase immunoglobulin-A (tTGA) levels and Marsh grading on duodenal histopathology in Celiac disease (CD).

METHODS

In a prospective cohort study, a total of 52 symptomatic patients between age group of 2-18 y were enroled. All enroled patients were subjected to upper GI endoscopy by an experienced endoscopist. Two biopsies each from the bulb (D1) and second part (D2) of the duodenum were taken and Marsh grading was performed by a single experienced pathologist. Serum tTGA levels were also performed to find out correlation between serum tTGA levels and Marsh grading.

RESULTS

The mean age of the patients was 8.21 ± 3.45 y (Range: 2-16 y). Anemia was the most common non-gastrointestinal (GI) sign and was present in 73% of the cases. However the authors could not find out any significant association between Marsh grading and hemoglobin levels (r = 0.32, p > 0.05). Serum tTGA levels were found to be positively correlated with Marsh grading (Spearmen correlation coefficient ρ = 0.74, p 0.000). Significant differences were found in tTGA levels between different Marsh gradings (ANOVA test) (p 0.000). Receiver-operator curve (ROC) analysis cut-off value of serum tTGA for predicting villous atrophy was 178.8 (nine times of cut-off value) with sensitivity of 100% and specificity of 85.7%.

CONCLUSIONS

Serum tTGA levels can be used to predict villous atrophy and biopsy may be avoided in strongly suspected cases with more than 9 times of cut-offs.

Recent advances in pediatric celiac disease

The incidence of celiac disease (CD) has increased over the last half-century, resulting in rising interest in identifying risk factors for CD. The necessity of duodenal biopsies in the diagnosis of CD has recently been challenged. Areas covered: This review covers the recent literature regarding the role of infant feeding practices, including breastfeeding and timing of gluten introduction, and the microbiota in the development of CD. Additionally, the application of the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for a non-biopsy approach to the diagnosis of CD is reviewed. Expert commentary: Recent investigations have not revealed any significant effect of breastfeeding or timing of gluten introduction on the risk of CD in at-risk populations. There are alterations in the microbiota of CD patients. However, the role of the microbiome and whether its manipulation has a clinical effect are unknown. Preliminary data suggests a non-biopsy approach to diagnosis of pediatric CD can be applied to several populations, although additional studies are needed. Prospective investigations are underway to examine the interplay of infant feeding practices and the microbiome and to identify particular CD-specific biomarkers that may aid in the diagnosis and ultimately prevention of CD.

Coeliac disease: further evidence that biopsy is not always necessary for diagnosis

OBJECTIVES

Growing evidence supports the view that the diagnosis of coeliac disease (CD) can be made by serological tests alone, although this approach is still not widely accepted. We previously showed in retrospective and prospective studies that in adults an IgA-tissue transglutaminase antibody cut-off can be defined above which the positive predictive value for CD is 100%. Following a change in the analytical method for measuring the antibody, our objectives were to re-examine this finding in a larger series of adults to ascertain whether a diagnosis of CD can be reliably made in a proportion of patients without the need for small bowel biopsy and to re-evaluate the diagnostic guidelines used in our centre.

PATIENTS AND METHODS

A retrospective analysis was done in an unselected series of 270 adult patients who had small bowel biopsies and serum IgA-tissue transglutaminase antibody levels measured from 2009 to 2014.

RESULTS

At an IgA-tissue transglutaminase antibody cut-off greater than 45 U/ml (>8×upper limit of normal+2SDs) the positive predictive value for CD in this cohort was 100%; 40% of cases were above this cut-off.

CONCLUSION

We have verified that a diagnosis of CD can be reliably made in a high proportion of adults based on serology alone using the IgA-tissue transglutaminase antibody method specified. These results add to the body of evidence that small bowel biopsy should no longer be considered mandatory for the diagnosis of CD. On the basis of these results the diagnostic guidelines in our centre have been modified.

Is the Diagnosis of Celiac Disease Possible Without Intestinal Biopsy?

BACKGROUND

Coeliac disease is defined as a state of immune-mediated hyper-responsiveness to dietary gluten from wheat, barley, or rye in genetically predisposed individuals that results in tissue damage. The diagnosis is made by microscopic examination of a small intestinal biopsy, although serological testing for antibodies against tissue transglutaminase and deamidated gliadin peptide can be of great advantage. It has been suggested that duodenal biopsy can be avoided in patients with high levels of the tissue transglutaminase antibody, since a relationship has been found to be present between tissue transglutaminase antibody titres and coeliac disease.

AIMS

To study the correlation between tissue transglutaminase titre and small intestinal biopsy findings in patients with coeliac disease.

STUDY DESIGN

Diagnostic accuracy study.

METHODS

Ninety-five cases of patients diagnosed with coeliac disease and with positive serum tissue transglutaminase titres were retrieved from the Jordan University Hospital archives between December 2014 and December 2015. All the cases were classified according to the Marsh classification.

RESULTS

Ninety-five cases with a positive titre for the antibody were included in this study, 73 (76.8%) of them were females and 22 cases (23.2%) were males. The age of the patients ranged between 4 and 75 years with a mean age ± standard deviation of 32.3±14.7. The sensitivity was the highest in Marsh IIIC and lowest in Marsh IIIA (95% versus 68% respectively). The specificity was moderate (76%) for all subtypes of Marsh III.

CONCLUSION

This study showed a positive correlation between the tissue transglutaminase titre and the degree of duodenal damage (Marsh IIIC) in patients with coeliac disease. In the presence of high tissue transglutaminase levels, duodenal biopsy might not be always necessary for diagnosis, particularly in symptomatic patients.

Celiac disease: a clinical review

Celiac disease (CD) is an immune-mediated inflammatory enteropathy triggered by gluten exposure in genetically susceptible individuals. It has a high prevalence approaching 1% of the US population. A high index of suspicion is warranted to diagnose CD as frequently patients present with extraintestinal or atypical manifestations. CD is diagnosed by a combination of serum serologies and duodenal biopsies. The majority of patients will respond to a lifelong gluten-free diet which is the cornerstone of therapy. Complications such as refractory CD, ulcerative jejunoileitis, enteropathy associated T-cell lymphoma and small bowel adenocarcinoma occur in a minority of patients.

Prediction of esophageal and gastric histology by macroscopic diagnosis during upper endoscopy in pediatric celiac disease

AIM

To determine the sensitivity of macroscopic appearance for predicting histological diagnosis at sites other than duodenum in pediatric celiac disease (CD).

METHODS

Endoscopic and histologic findings in pediatric patients undergoing upper endoscopy for first-time diagnosis of CD at Stollery Children’s Hospital from 2010-2012 were retrospectively reviewed.

RESULTS

Clinical charts from 140 patients were reviewed. Esophageal and gastric biopsies were taken in 54.3% and 77.9% of patients, respectively. Endoscopic appearance was normal in the esophagus and stomach in 75% and 86.2%. Endoscopic esophageal diagnoses were eosinophilic esophagitis (EE) (11.8%), esophagitis (7.9%), glycogenic acanthosis (1.3%) and non-specific abnormalities (3.9%). Endoscopic gastric diagnoses were gastritis (8.3%), pancreatic rest (0.9%), and non-specific abnormalities (4.6%). Histology was normal in 76.3% of esophageal and 87.2% of gastric specimens. Abnormal esophageal histology was EE (10.5%), esophagitis (10.5%), glycogenic acanthosis (1.3%) and non-specific (1.3%). Gastritis was reported in 12.8% of specimens. Sensitivity and specificity of normal endoscopy for predicting normal esophageal histology was 86.2% and 61.1%, and for normal gastric histology was 87.4% and 21.4%.

CONCLUSION

In the absence of macroscopic abnormalities, routine esophageal and gastric biopsy during endoscopy for pediatric CD does not identify major pathologies. These findings have cost and time saving implications for clinical practice.

Identification of a serum transglutaminase threshold value for the noninvasive diagnosis of symptomatic adult celiac disease patients: a retrospective study

BACKGROUND

A celiac disease (CD) diagnosis is based on duodenal histology, with the exception of children showing anti-tissue transglutaminase (anti-tTG) serum levels exceeding ten times the cut-off. Our aim was to reproduce this simplified approach in adults, identifying an anti-tTG threshold value useful to diagnose CD without endoscopic procedures.

METHODS

A total of 671 adult CD patients were subjected to blood sampling to determine anti-tTG serum levels, as well as to endoscopy with biopsy to perform duodenal histology. The anti-tTG serum levels/cut-off ratio was compared with the degree of duodenal lesions.

RESULTS

Anti-tTG serum levels/cut-off ratio determined in patients with type IIIc was significantly higher than that measured in patients with type IIIb (p < 0.001), IIIa (p < 0.001), II (p < 0.05) and 0 (p < 0.001) of Marsh-Oberhuber histological classification. A significant correlation (r = 0.297, p < 0.0001) was found between the anti-tTG serum levels/cut-off ratio and the degree of duodenal lesions. The anti-tTG serum levels/cut-off ratio was classified as an accurate parameter (AUC = 0.715, p < 0.0001), with the best diagnostic performance obtained considering the threshold value >3.6 (sensitivity = 76.8 %, PPV = 97.2 %).

CONCLUSIONS

The anti-tTG serum levels/cut-off ratio correlates with the degree of duodenal lesions and, if used with the threshold value >3.6, could avoid endoscopy with biopsy in about 75 % of seropositive adults waiting for CD diagnosis. However, since this procedure could also imply CD diagnosis in almost 3 % of seropositive patients with normal villous architecture, a consensus opinion is needed to suggest its use in the diagnosis of adult CD.

Contemporary celiac disease diagnosis: is a biopsy avoidable?

PURPOSE OF REVIEW

The duodenal biopsy is the gold standard for the diagnosis of celiac disease. However, given improvements in the performance of serological testing, the possibility of accurately diagnosing celiac disease without the need of a biopsy has attracted interest. The European Society for Paediatric Gastroenterology, Hepatology and Nutrition has revised its recommendations to include a diagnostic algorithm that includes sequential serological testing and human leukocyte antigen genotyping for symptomatic children which would enable a diagnosis of celiac disease to be made in the absence of a confirmatory intestinal biopsy.

RECENT FINDINGS

Recent studies have evaluated the ESPGHAN guidelines and have mostly corroborated that celiac disease can be accurately diagnosed in specific pediatric patient populations without the need of a biopsy. However, two cautionary points have been raised that warrant further consideration - the success of this approach is highly dependent targeting a population with a high pretest probability of celiac disease, as well, the performance of serology assays must be established and the appropriate use of cutoffs is essential.

SUMMARY

The duodenal biopsy will remain the gold standard for diagnosing celiac disease in a majority of patients. However, as serology assays evolve and as a greater understanding of the genetic risk factors of celiac disease is achieved, more patients may be accurately diagnosed without the need for a biopsy.

A Canadian Study toward Changing Local Practice in the Diagnosis of Pediatric Celiac Disease

Background. The European Society for Pediatric Gastroenterology, Hepatology and Nutrition endorses serological diagnosis (SD) for pediatric celiac disease (CD). The objective of this study was to pilot SD and to prospectively evaluate gastrointestinal permeability and mucosal inflammation at diagnosis and after one year on the gluten-free diet (GFD). We hypothesized that SD would be associated with similar short term outcomes as ED. Method. Children, 3-17 years of age, referred for possible CD were eligible for SD given aTTG level ≥200 U/mL, confirmed by repeat aTTG and HLA haplotypes. Gastrointestinal permeability, assessed using sugar probes, and inflammation, assessed using fecal calprotectin (FC), at baseline and after one year on a GFD were compared to patients who had ED. Results. Enrolled SD (n = 40) and ED (n = 48) patients had similar demographics. ED and SD groups were not different in baseline lactulose: mannitol ratio (L : M) (0.049 versus 0.034; p = 0.07), fractional excretion of sucrose (%FES; 0.086 versus 0.092; p = 0.44), or fecal calprotectin (FC; 89.6 versus 51.4; p = 0.05). At follow-up, urine permeability improved and was similar between groups, L : M (0.022 versus 0.025; p = 0.55) and %FES (0.040 versus 0.047; p = 0.87) (p > 0.05). FC improved but remained higher in the SD group (37.1 versus 15.9; p = 0.04). Conclusion. Patients on the GFD showed improved intestinal permeability and mucosal inflammation regardless of diagnostic strategy. This prospective study supports that children diagnosed by SD have resolving mucosal disease early after commencing a GFD.

Overview of biomarkers for diagnosis and monitoring of celiac disease

Among the adverse reactions caused by wheat, celiac disease (CD) is the longest studied and best-known pathology. The more recently defined non-celiac gluten sensitivity (NCGS) presents with symptoms which are often indistinguishable from CD. Diagnosis of CD is based on serologic, molecular, and bioptic testing. The IgA anti-transglutaminase (tTG) test is considered highly important, as it shows high sensitivity and specificity and its levels correlate to the degree of intestinal damage. Small bowel biopsy can be avoided in symptomatic patients with IgA anti-tTG levels above 10× the manufacturer's cut-off. Recently, tests of anti-deamidated peptides of gliadin (DGP) have replaced classic anti-native gliadin (AGA) tests. DGP assays have a considerably higher diagnostic accuracy than AGA assays, especially in the IgG class, and can replace anti-tTG tests in patients with selective IgA deficiency. The combination of IgG anti-DGP plus IgA anti-tTG assays show greater sensitivity than a single test, with very high specificity. EMA tests have great diagnostic accuracy but are not recommended by all the latest guidelines because they are observer dependent. Biopsy must still be considered the gold standard for CD diagnosis. HLA-DQ genotyping can be used to screen asymptomatic children and in cases of histology/serology disagreement. About half of NCGS patients are DQ2 positive and have IgG AGA. To diagnose NCGS, first CD and wheat allergy must be excluded; then the wheat dependence of symptoms must be verified by a gluten-free diet and subsequent gluten challenge.

The presence of anti-endomysial antibodies and the level of anti-tissue transglutaminases can be used to diagnose adult coeliac disease without duodenal biopsy

BACKGROUND

The new ESPGHAN guidelines for diagnosis of paediatric coeliac disease suggest to avoid biopsy in genetically pre-disposed and symptomatic individuals with positive anti-endomysial antibodies (EMA) and anti-tissue transglutaminases (a-tTG). However, duodenal biopsy remains the gold standard in adult coeliac disease.

AIMS

To establish the cut-off values of a-tTG, which would: predict the presence of duodenal histology (Marsh ≥2) diagnostic for coeliac disease; and predict the presence of villous atrophy (Marsh 3) in adults.

METHODS

We performed an observational prospective study including all consecutive adult patients with suspected coeliac disease. All subjects were tested for EMA and a-tTG. Coeliac disease diagnosis was made in presence of Marsh ≥2, a-tTG >7 U/mL and positive EMA. A ROC curve was constructed to establish the best specificity cut-off of a-tTG levels, which would predict the presence of Marsh ≥2 and Marsh 3 at histology.

RESULTS

The study included 310 patients with positive antibodies. Histology showed Marsh 1 in 8.7%, Marsh 2 in 3.5%, Marsh 3 in 87.7%. The best cut-off value of a-tTG for predicting Marsh ≥2 was 45 U/mL (sensitivity 70%; specificity 100%; PPV 100%; NPV 24.1%); the best cut-off for predicting villous atrophy was 62.4 U/mL (sensitivity 69%, specificity 100%; PPV 100%; NPV 31%).

CONCLUSIONS

The diagnosis of coeliac disease can be reached without histology in adult patients with positive EMA and a-tTG levels >45 U/mL. An a-tTG level >62.4 was diagnostic for villous atrophy. These results could contribute to improving the diagnosis of coeliac disease by allowing for a significant reduction in diagnosis-related costs.

Coeliac autoimmunity in type I diabetes mellitus

BACKGROUND AND STUDY AIMS

Coeliac autoimmunity (CA) has a known association with type 1 diabetes mellitus (T1DM) for which screening is routinely recommended but less frequently followed. The impact of CA in T1DM has been variably reported. The aims of this study are as follows: (1) to study the prevalence of CA in patients with T1DM and (2) to study the impact of CA not only on nutritional parameters but also on glycaemic control, endocrine axes and bone health.

PATIENTS AND METHODS

Eighty-six consecutive patients with T1DM were screened for CA using immunoglobulin A (IgA) tissue transglutaminase as a marker (TTG; IgG anti-gliadin in IgA-deficient case). CA positive (CA+) cases were compared with age-matched and sex-matched CA negative (CA-) T1DM cases for anthropometry, glycaemic control (assessed by glycated haemoglobin (HbA1c) and hypoglycaemic/hyperglycaemic episodes), endocrine (thyroid function, cortisol, growth hormone (GH) axis, gonadal axes), haematological (haemoglobin, iron profile and vitamin B12 status) and calcium metabolism parameters and bone densitometry (by dual-energy X-ray absorptiometry (DXA)). Consenting patients with CA also underwent upper gastrointestinal (GI) endoscopy with duodenal biopsy.

RESULTS

Out of 86 patients, 11 (12.75%) screened positive for CA (seven patients underwent duodenal biopsies which were suggestive of Marsh grade III(2), II(3) and I(2) disease). The CA+ T1DM patients were comparable with CA- T1DM in terms of anthropometry. CA+ patients had higher HbA1c (10.7±1.8 vs. 8.4±1.0 (93±19 vs. 68±11 mmol/mol); p<0.01), more hypoglycaemic episodes (five vs. two; p<0.05), higher prevalence of iron and vitamin B12 deficiency, lower insulin-like growth factor-1 (IGF-1) levels and lower bone mineral density (BMD) z-score at total body (-1.91±1.05 vs. -0.63±0.73; p<0.05) and lumbar spine (-1.69±0.92 vs. -0.36±0.93; p<0.05). The incidence of fractures in the past 3years was also more in CA+ patients than in CA- patients (four vs. one; p<0.05).

CONCLUSION

CA has an important autoimmune association with T1DM. The concomitant presence of CA adversely affects stature, bone health, glycaemic control and iron and B12 levels in T1DM. IgA sufficiency should be ensured before using an IgA-based screening test for CA.

Characteristics of patients who avoid wheat and/or gluten in the absence of Celiac disease

BACKGROUND

Gastrointestinal symptoms that respond to the removal of wheat and/or gluten are becoming more common. Patients who avoid wheat and/or gluten (PWAWG) are a heterogeneous group and predominantly self-diagnosed prior to presenting for clinical evaluation.

SPECIFIC AIM

We characterized PWAWGs seen at a tertiary care referral center and compared them to patients with celiac disease (CD) and subjects in the National Health and Nutrition examination survey (NHANES).

METHODS

This was a cross-sectional study evaluating patients seen by four gastroenterologists at a CD referral center. Baseline characteristics, laboratory values, and medical comorbidities were compared to CD patients who presented at the same center and subjects enrolled in NHANES.

RESULTS

Eighty-four PWAWGs were identified and compared to 585 CD patients and 2,686 NHANES patients. Thirty-two alternative diagnoses were made in 25 (30%) PWAWGs, including small intestinal bacterial overgrowth and fructose/lactose intolerance. When compared to patients with CD, PWAWGs had similar body mass index (BMI, 23.1 vs. 23.5, p = 0.54) and mean hemoglobin value (13.4 vs. 13.3, p = 0.6). When compared to male and female patients in NHANES, BMI, folate, and mean hemoglobin values were lower in PWAWGs. Both male and female PWAWGs had a lower prevalence of hypertension.

CONCLUSION

While there are similarities between CD and PWAWGs that could possibly be due to shared HLA haplotypes or an effect of the gluten-free diet, alternative diagnoses are common in these patients. PWAWGs have a similar cardiovascular profile as CD patients in terms of lower BMI and lower prevalence of hypertension.

Mass population screening for celiac disease in children: the experience in Republic of San Marino from 1993 to 2009

Background

Prevalence of celiac disease in developed countries is assessed about 1:100–1:150. The real prevalence is unknown because mass screenings are expensive and difficult to organize. Moreover celiac disease can affect people at every age and studies on asymptomatic subjects at different ages are not comparable. In this study we wanted to know the real prevalence of celiac disease in children in the Republic of San Marino. We also analysed concordance of different tests used and costs of mass screening.

Methods

The study started in 1993. From 1993 to 1997 children aged 6, 10 and 14 were screened. Since 1997 only children aged 6 were monitored, in order to have a homogeneous population. In fact, every child born since 1980 was taken into account. Children were recruited by classroom lists of students for general paediatric examination. Until 2005 the screening test was based on dosage of antibodies anti-gliadin (AGA) IgA and IgG on venous blood. Since 2006 these tests were replaced by anti-transglutaminase IgA antibodies (ATTG). Anti-endomysial antibodies (EMA) were performed if result of any between either AGA or ATTG tests was positive or borderline; if EMA was positive, then an endoscopy with histological examination was performed to confirm the final diagnosis.

Results

Attendance to paediatric examination was 96%, submission to blood test was 87%. 42 on 5092 (0,8%; 1:125) children resulted affected by celiac disease. Histology always confirmed diagnosis by serology except for two cases. AGA test (until 2005) yielded 28 on 4304 (0,7% 1:143); ATTG test (since 2006) revealed 14 positive cases on 788 (1,8%; 1:55) leading to a larger percentage of diagnosis. EMA antibodies always confirmed positivity of ATTG.

Conclusions

Prevalence of celiac disease in children of Republic of San Marino is comparable to other North-European Countries. Sensitivity of ATTG proved much higher than that of anti-gliadin antibodies. Concordance between ATTG and EMA was 100%. Concordance between serology and histology was approximately 100%. Cost of screening was yearly about 5000 euros (250 children screened every year).

Correlation between antibodies and histology in celiac disease: incidence of celiac disease is higher than expected in the pediatric population

The present study aims to report on the correlation between the degree of negativity of anti-endomysial antibodies and anti-tissue transglutaminase antibodies in the IgA and IgG classes with regard to histological grade, in 44 newly diagnosed children with celiac disease (CD). Samples with negative antibodies, but a positive histology from a 5-year program searching for CD in the pediatric population were collected. A total of 4247 biopsy samples were used in this study. We documented that certain pediatric patients are seronegative, while the disease is active and the incidence of CD is higher than expected in the pediatric population. This is an important finding, which demonstrates the lack of association between autoantibodies and lesions, and justifies the use of biopsies for an accurate CD diagnosis and the importance of revising the diagnostic criteria in a clinical, endoscopic and serological context. We recommend a more active search for incidences of the disease in the pediatric population. Serological markers are not the main method for the diagnosis of CD as they are considered to only have a supporting role clinically. Biopsies of the small intestine are always necessary for the diagnosis of CD in these patients.

Red cell distribution width can predict intestinal atrophy in selected patients with celiac disease

BACKGROUND

Red cell distribution width (RDW) has been shown as a distinctive marker of mortality and morbidity in a wide spectrum of conditions related to systemic inflammation or deficiency of antioxidant nutrients.

OBJECTIVE

We aimed to investigate the predictive value of RDW in detection of intestinal atrophy in celiac disease (CD).

METHODS

Iron indices and RDW were studied in 49 patients with CD to evaluate the utilization of RDW as a predictive marker for presence of intestinal atrophy.

RESULTS

Sixty-nine percent of patients had iron deficiency at initial presentation and 89% had abnormal RDW defined as >14. Receiver operating characteristics curves of RDW has been found to be a predictive of intestinal atrophy at levels higher than 17.25 (68% sensitivity and 85% specificity). In patients with transglutaminase antibody IgA titers >200 U/l, RDW level >17.75 showed 76% sensitivity and 100% specificity for intestinal atrophy.

CONCLUSIONS

We suggest that RDW can be used as a surrogate marker of atrophy in patients with iron deficiency and suspected CD. In addition, the sensitivity, specificity, negative and positive predictive values of RDW increases when used in combination with high levels of transglutaminase IgA antibody.

Diagnosis of celiac disease in adults based on serology test results, without small-bowel biopsy

BACKGROUND & AIMS

Celiac disease is underdiagnosed, with nonspecific symptoms and high morbidity. New diagnostic factors are needed. We aimed to estimate the frequency at which adult patients with positive results from serology tests are referred for small-bowel biopsies and to identify factors that improve the diagnosis of celiac disease.

METHODS

We performed a retrospective analysis of data from 2477 subjects who received serology tests for celiac disease between 2005 and 2007. We analyzed results for total levels of IgA, IgA against human tissue transglutaminase (hTTG), IgA and IgG against gliadin, as well as dilution titers of IgA against endomysial antibodies (EMA). Biopsy samples were analyzed by pathologists experienced in detecting mucosal changes associated with celiac disease and graded according to the Marsh system.

RESULTS

Of the 2477 patients, 610 (25%) had abnormal results from serology tests, and 39% of these patients (240 of 610) underwent small-bowel biopsy analyses. Of these patients, 50 (21%) had biopsy findings consistent with celiac disease (Marsh 3 lesions) and were placed on gluten-free diets. Titers of IgA hTTG greater than 118 U identified patients with celiac disease with a 2% false-positive rate. Titers of 21 to 118 U, in combination with an EMA dilution titer of 1:160 or greater, had a positive predictive value of 83% for celiac disease. IgA hTTG levels less than 20 U, in combination with an EMA dilution titer less than 1:10, had a negative predictive value of 92% for celiac disease.

CONCLUSIONS

Serum levels of IgA hTTG greater than 118 U, or 21 to 118 U in combination with an EMA dilution titer of 1:160 or greater, can be used to identify adult symptomatic patients with celiac disease, in the absence of a small-bowel biopsy.

Intestinal biopsy is not always required to diagnose celiac disease: a retrospective analysis of combined antibody tests

Background

The objective of this study was to compare celiac disease (CD)– specific antibody tests to determine if they could replace jejunal biopsy in patients with a high pretest probability of CD.

Methods

This retrospective study included sera from 149 CD patients and 119 controls, all with intestinal biopsy. All samples were analyzed for IgA and IgG antibodies against native gliadin (ngli) and deamidated gliadin peptides (dpgli), as well as for IgA antibodies against tissue transglutaminase and endomysium.

Results

Tests for dpgli were superior to ngli for IgG antibody determination: 68% vs. 92% specificity and 79% vs. 85% sensitivity for ngli and dpgli, respectively. Positive (76% vs. 93%) and negative (72% vs. 83%) predictive values were also higher for dpgli than for ngli. Regarding IgA gliadin antibody determination, sensitivity improved from 61% to 78% with dpgli, while specificity and positive predictive value remained at 97% (P < 0.00001). A combination of four tests (IgA anti-dpgli, IgG anti-dpgli, IgA anti- tissue transglutaminase, and IgA anti-endomysium) yielded positive and negative predictive values of 99% and 100%, respectively and a likelihood ratio positive of 86 with a likelihood ratio negative of 0.00. Omitting the endomysium antibody determination still yielded positive and negative predictive values of 99% and 98%, respectively and a likelihood ratio positive of 87 with a likelihood ratio negative of 0.01.

Conclusion

Antibody tests for dpgli yielded superior results compared with ngli. A combination of three or four antibody tests including IgA anti-tissue transglutaminase and/or IgA anti- endomysium permitted diagnosis or exclusion of CD without intestinal biopsy in a high proportion of patients (78%). Jejunal biopsy would be necessary in patients with discordant antibody results (22%). With this two-step procedure, only patients with no CD-specific antibodies would be missed.

Prevalence and natural history of potential celiac disease in at-family-risk infants prospectively investigated from birth

OBJECTIVE

To evaluate the frequency and the natural history of potential (serology positive/Marsh 0-1 histology) celiac disease (CD) in children with a family risk of CD and factors associated with potential instead of overt (serology positive/Marsh 2-3 histology) CD expression.

STUDY DESIGN

Two-year follow-up study of 96 children (57 females; mean age: 29 ± 12 months) prospectively investigated from birth with: (1) a CD-affected first-degree relative; (2) positivity of serum IgA anti-tissue transglutaminase (tTG) or IgG antigliadin and IgA deficiency; and (3) the results of small intestinal biopsy. Children with potential CD were advised to remain on a gluten containing diet, repeat the celiac antibodies every 6 months, and to have an intestinal biopsy performed in case of persistently high anti-tTG level. Factors discriminating between potential and overt CD were analyzed by decision tree analysis based on the C4.5 algorithm.

RESULTS

Twenty-four children had potential and 72 overt CD. The stronger predictors of potential CD were lack of symptoms, anti-tTG level lower than 11-fold the upper normal limit, age lower than 24 months, and breastfeeding longer than 8 months. Eighteen out of 21 (86%) patients with potential CD continuing a gluten-containing diet became antibody negative, 1/21 (5%) developed overt CD, and 2/21 (9%) had fluctuating antibodies levels after 2 years.

CONCLUSIONS

The prevalence of potential CD and the percentage of short-term loss of CD-related-antibodies are high in infants at-family-risk for CD. In symptomless children with a positive celiac serology, the decision of performing an intestinal biopsy should be preceded by a period of repeated serological testing.

Tissue transglutaminase levels above 100 U/mL and celiac disease: A prospective study

AIM: To investigate whether a tissue-transglutaminase antibody (tTGA) level ≥ 100 U/mL is sufficient for the diagnosis of celiac disease (CD).

METHODS: Children suspected of having CD were prospectively included in our study between March 2009 and September 2011. All patients with immune globulin A deficiency and all patients on a gluten-free diet were excluded from the study. Anti-endomysium antibodies (EMA) were detected by means of immunofluorescence using sections of distal monkey esophagus (EUROIMMUN, Luebeck, Germany). Serum anti-tTGA were measured by means of enzyme-linked immunosorbent assay using human recombinant tissue transglutaminase (ELiA Celikey IgA kit Phadia AB, Uppsala, Sweden). The histological slides were graded by a single experienced pathologist using the Marsh classification as modified by Oberhuber. Marsh II and III lesions were considered to be diagnostic for the disease. The positive predictive values (PPVs), negative predictive values (NPVs), sensitivity and specificity of EMA and tTGA along with their 95% CI (for the cut off values > 10 and ≥ 100 U/mL) were calculated using histology as the gold standard for CD.

RESULTS: A total of 183 children were included in the study. A total of 70 (38.3%) were male, while 113 (61.7%) were female. The age range was between 1.0 and 17.6 years, and the mean age was 6.2 years. One hundred twenty (65.6%) patients had a small intestinal biopsy diagnostic for the disease; 3 patients had a Marsh II lesion, and 117 patients had a Marsh III lesion. Of the patients without CD, only 4 patients had a Marsh I lesion. Of the 183 patients, 136 patients were positive for EMA, of whom 20 did not have CD, yielding a PPV for EMA of 85% (95% CI: 78%-90%) and a corresponding specificity of 68% (95% CI: 55%-79%). The NPV and specificity for EMA were 91% (95% CI: 79%-97%) and 97% (95% CI: 91%-99%), respectively. Increased levels of tTGA were found in 130 patients, although only 116 patients truly had histological evidence of the disease. The PPV for tTGA was 89% (95% CI: 82%-94%), and the corresponding specificity was 78% (95% CI: 65%-87%). The NPV and sensitivity were 92% (95% CI: 81%-98%) and 97% (95% CI: 91%-99%), respectively. A tTGA level ≥ 100 U/mL was found in 87 (47.5%) patients, all of whom were also positive for EMA. In all these 87 patients, epithelial lesions confirming CD were found, giving a PPV of 100% (95%CI: 95%-100%). The corresponding specificity for this cut-off value was also 100% (95% CI: 93%-100%). Within this group, a total of 83 patients had symptoms, at least gastrointestinal and/or growth retardation. Three patients were asymptomatic but were screened because they belonged to a group at risk for CD (diabetes mellitus type 1 or positive family history). The fourth patient who lacked CD-symptoms was detected by coincidence during an endoscopy performed for gastro-intestinal bleeding.

CONCLUSION: This study confirms based on prospective data that a small intestinal biopsy is not necessary for the diagnosis of CD in symptomatic patients with tTGA ≥ 100 U/mL.

IgA antibodies against deamidated gliadin peptides in patients with chronic liver diseases

BACKGROUND/AIMS

IgA antibodies against tissue-transglutaminase (anti-tTG-IgA) and IgA and IgG antibodies against deamidated gliadin peptides (anti-DGP-IgA and anti-DGP-IgG) are considered specific for celiac disease (CD) whereas, patients with chronic liver disorders have an increased risk of latent CD development. We investigated the prevalence and clinical significance of anti-DGP-IgA, anti-DGP-IgG and anti-tTG-IgA in a large cohort of patients with chronic liver diseases.

METHODS

668 patients without gastrointestinal symptoms (426 viral hepatitis, 94 autoimmune liver diseases, 61 alcoholic disease, 46 non-alcoholic fatty liver disease, 41 with other liver disorders) were investigated by ELISAs (INOVA Diagnostics). Patients positive for at least one autoantibody invited for a small-intestinal biopsy and HLA-DQ typing.

RESULTS

Anti-DGP-IgA were detected in 8.5%, anti-DGP-IgG in only one (0.15%, P<0.001) and anti-tTG-IgA in 5.8% of patients (P=0.05). Fifty-two were anti-DGP-IgA(+)/anti-tTG-IgA(-), 34 anti-DGP-IgA(-)/anti-tTG-IgA(+), and 5 anti-DGP-IgA(+)/anti-tTG-IgA(+). Anti-DGP-IgA positivity was associated with older age (P<0.05), cirrhosis (P<0.05) and increased IgA (P<0.05) whereas, anti-tTG-IgA only with cirrhosis (P<0.05). Histology and HLA-typing compatible with CD was revealed in 4/14 anti-DGP-IgA(+)/anti-tTG-IgA(-), 0/13 anti-DGP-IgA(-)/anti-tTG-IgA(+) and 2/2 anti-DGP-IgA(+)/anti-tTG-IgA(+). All 6 patients diagnosed with CD were anti-DGP-IgA(+) and only 2 anti-tTG-IgA(+).

CONCLUSIONS

Although a significant number of patients had detectable CD-related autoantibodies, anti-DGP-IgA test seems better than anti-tTG-IgA for unmasking occult forms of CD in patients with chronic liver disorders. The known good performance for CD diagnosis of anti-DGP-IgG test was not confirmed in this specific group of patients.

High tissue-transglutaminase antibody level predicts small intestinal villous atrophy in adult patients at high risk of celiac disease

BACKGROUND

Duodenal biopsy may be unnecessary to confirm celiac disease in patients with high tissue-transglutaminase antibody level.

AIMS

To define a cut-off value of tissue-transglutaminase antibody with high positive likelihood ratio for duodenal atrophy in patients with suspected celiac disease.

METHODS

We retrospectively identified 945 patients with suspected celiac disease and classified according to the method used for tissue-transglutaminase antibody assay: Group A (n=393, Eu-tTG® Eurospital), Group B (n=263; Eu-tTG® Eurospital) and Group C (n=289; Celikey® Phadia). Duodenal histology was graded according to Marsh. Sensitivity, specificity, and positive likelihood ratio were used to evaluate cut-off points of tissue-transglutaminase antibody as predictor of villous atrophy.

RESULTS

100% specificity and ∞ positive likelihood ratio for duodenal atrophy was observed at a cut-off value of tissue-transglutaminase antibody 5 times higher than the upper limit of normal. CD diagnosis was confirmed by concordance with antiendomysial antibodies, and by reduction of t-TG titre in all patients and improvement of duodenal histology in 80% during gluten-free diet.

CONCLUSIONS

Tissue-transglutaminase antibody level 5-folds the upper limit of normal is 100% specific for duodenal atrophy and using this cut-off biopsy could by avoided in 1/3 of patients. Diagnostic criteria of celiac disease in adults need revision.

Advances in coeliac disease

PURPOSE OF REVIEW

This article critically summarizes the recent scientific and clinical advances in coeliac disease.

RECENT FINDINGS

Epidemiological studies have shown that coeliac disease is as common in parts of Asia, Africa and Eastern Europe as in the western world. Genome-wide association studies continue to identify genetic susceptibilities that are both unique to coeliac disease and overlap with other autoimmune diseases. Human leukocyte antigen genotyping offers additional sensitivity in detecting coeliac disease in individuals who have self-prescribed gluten-free diets (GFD) or have atypical presentations. Immunological advances have highlighted the potential proinflammatory pitfalls of vitamin A supplementation in active coeliac disease and have enabled identification of oat and barley subsets that may be safely incorporated into coeliac diets. Large population-based studies have expanded our knowledge of the long-term risks of coeliac disease, in addition to excluding infertility as a cause for concern once a GFD has been established.

SUMMARY

The long-term implications of active coeliac disease emphasize the need for early detection and strict adherence to GFD, which remains the cornerstone of management. Technological advances in food modulation and immuno-therapies offer promise, but remain in the translational phases of clinical trials at present.