Correlation Between IgA Tissue Transglutaminase Antibody Ratio and Histological Finding in Celiac Disease
ABSTRACT Positivity of both immunoglobulin A anti-tissue transglutaminase (TTG) and anti-endomysium antibodies (EMA) has a positive predictive value of nearly 100% for celiac disease (CD). The objective of the present study was to evaluate whether patients of any age, with high pretest probability of CD and high titre of anti-TTG and EMA positivity, have a high probability of intestinal damage and may not require the biopsy for final diagnosis.
A retrospective analysis of 412 consecutively referred patients, age range 10 months to 72 years, who underwent small-bowel biopsy for suspicion of CD and positivity to both anti-TTG and EMA, was performed at 4 Italian centers. Biopsies were evaluated independently by 2 pathologists using Marsh modified classification; in cases of dissimilar results, a third pathologist examined the biopsy. The final histological finding diagnosis was expressed as the prevalent or highest score assigned by the pathologist board.
Three hundred ninety-six patients (96.1%) had histological findings consistent with CD (grade 2 and 3a, 3b, or 3c of modified Marsh classification). An anti-TTG ratio ≥ 7 was able to identify with the 3 assays used (Celikey, anti-TTG immunoglobulin A, EuTTG) all of the patients with significant mucosal damage (Marsh ≥ 2) independent of age and sex; specificity and positive predictive value were 100%. An anti-TTG ratio >20 was more specific (99.8%) for identification of patients with villous atrophy (Marsh 3 a, b, or c).
Patients with positivity of anti-TTG ≥ 7-fold cutoff, confirmed by positivity to EMA, have a high-degree probability of duodenal damage. In selected conditions, a duodenal biopsy may be avoided and a confirmed greatly positive anti-TTG result could be the basis to prescribe a gluten-free diet.
SourceAvailable from: Ying-Yong Zhao[Show abstract] [Hide abstract]
ABSTRACT: 1. Overview of Biomarkers for Diagnosis and Monitoring of Celiac Disease 2. Cystatin C: A Kidney Function Biomarker 3. Procalcitonin: Potential Role in Diagnosis and Management 4. Manganese Superoxide Dismutase and Oxidative Stress Modulation 5. Selenium and Selenium-Dependent Antioxidants in Chronic Kidney Disease 6. Lipidomics:New Insight Into Kidney DiseaseAdvances in clinical chemistry 02/2015; 68. · 4.30 Impact Factor
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ABSTRACT: 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. AimsTo 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 >7U/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. ResultsThe 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 45U/mL (sensitivity 70%; specificity 100%; PPV 100%; NPV 24.1%); the best cut-off for predicting villous atrophy was 62.4U/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 >45U/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.Alimentary Pharmacology & Therapeutics 09/2014; 40(10). DOI:10.1111/apt.12970 · 4.55 Impact Factor
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ABSTRACT: The serological diagnosis of celiac disease (CD) often relies on the presence of anti-tissue transglutaminase (tTG) IgA autoantibodies. Patients suffering from selective IgA deficiency (IgAD) are often not aware of their IgA deficiency and are tested as CD negative, delaying considerably the diagnosis. The detection of IgG against deamidated gliadin peptides (DGP) has high specificity and better sensitivity than IgG anti-tTG. A multi-analytic lateral-flow immunochromatographic assay (CD-LFIA) based on the detection of IgA and IgG anti-DGP and total IgA was shown to have a good diagnostic accuracy for CD. The aim of this study was to evaluate the clinical accuracy of its use in children suffering from IgAD.BMC Gastroenterology 11/2014; 14(1):186. DOI:10.1186/1471-230X-14-186 · 2.11 Impact Factor