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Background: The introduction of an ELISA for antibodies to tissue transglutaminase has opened an new era in the diagnosis of coeliac disease by offering a simple, reliable and observer non-dependent method for the identification of coeliac patients. Despite its high sensitivity and specificity, false negative results can be achieved if a total serum IgA deficiency occurs. IgA deficient sera need to be tested to assess the level of total serum IgA to exclude possible false negative results.Aim: The aim of this study was to evaluate whether it is possible to define a cut-off value for an anti tissue transglutaminase ELISA which could indicate total IgA deficiency. In such patients further IgA isotype testing would only be necessary.Methods: 75 sera from patients with total IgA serum deficiency (<0.05 g/L), 21 patients with low IgA levels (<0.16 g/L) were tested by means of an ELISA method for the detection of anti-tissue transglutaminase antibodies (Eu-tTG®IgA, Eurospital, Italy). Five patients (including 2 subjects affected by coeliac disease) with normal IgA values (>0.2 g/L) were used as controls.Results: Total IgA deficient sera: 75/75 sera gave anti TGA values <0.2 AU/ml Low serum IgA values: 19/21 sera gave TGA values below 1 AU/ml All the normal serum IgA sera gave values above 1 AU/ml. The CD patients had values of 14.1 and 14.6 AU/ml respectively.Conclusion: These results are preliminary data and need to be confirmed by means of additional data. However, total serum IgA deficient sera did not show Eu-tTG® IgA values above 1 AU/ml.The use of a cut-off value at 1 AU/ml might be useful in deciding whether to perform total IgA serum determinations in those patients whose serum TGA values are lower than 1 AU/ml. [Copyright &y& Elsevier]

Introduction: We present the development and validation of an ELISA test based on human recombinant tissue transglutaminase (h-tTG) for the detection of IgG anti-transglutaminase (IgG anti-h-tTG).Objective: To demonstrate that Eu-tTG® IgG umana kit is of help in diagnosing coeliac patients with IgA deficiency.Subjects: 154 sera were from healthy anti-endomysium (AEA, Antiendomysium Eurospital) and IgA anti-transglutaminase (IgA anti-h-tTG, Eu-tTG IgA umana®, Eurospital) negative subjects, 105 were from celiac patients all AEA and IgA anti-h-tTG positive and 11 sera were from IgA deficient celiac patients negative for both AEA and IgA anti-h-tTG.Results: 3 out of 154 healthy subjects were above the cut-off values for IgG anti-h-tTG (specificity of 98%). 50 out of 105 celiac patients were negative for IgG anti-h-tTG (sensitivity of 52%). All 11 IgA deficient celiac patients were positive for IgG anti-h-tTG (sensitivity of 100%).Conclusions: These results show that Eu-tTG®IgG umana kit has good specificity for screening purposes. The sensitivity is very low with celiac patients that are able to produce anti-transglutaminase IgA but is very high (>99%) with those patients that are unable to produce IgA antibodies. The combined use of Eu-tTG®IgG umana and the Eu-tTG®IgA umana seems to provide the most powerful diagnostic tool for the screening of celiac disease to date. [Copyright &y& Elsevier]

Background: Between November 2000 and February 2001 a study has been performed by eight Italian hospital centers with the aim of verifying the usefulness of Calprest® (detection of fecal calprotectin) as a marker of bowel inflammation. Preliminary data are reported.Objective: To define the use of fecal calprotectin as a marker of intestinal inflammation, to assess whether it might help in differentiating between IBS and IBD, and its role in IBD.Subjects: Healthy population (51), active Crohn (16), non active or under remission Crohn (11), active ulcerative Colitis (8), non active or under remission ulcerative Colitis (13), pathological Controls of various nature (79).Results: The calculated cut-of value was 65 μgr/gr.42/51 healthy subjects were negative. 16/16 patients with active CD were all positive. 8/8 patients with RCU were also positive.Conclusion: Calprest® might become an important tool in the in-vitro diagnosis of patients referred to the gastroenterology departments. The results achieved in this study demonstrate that a negative test result is an index of absence of inflammatory bowel disease.High Calprest® values (fecal calprotectin) are present, as highlighted by this study, in patients with inflammatory bowel disease. [Copyright &y& Elsevier]