IgA and IgG antitransglutaminase 2 antibodies in the diagnosis of celiac disease

Screening for celiac disease (CD) dramatically improved when techniques able to measure blood autoantibodies against tissue transglutaminase 2 (TTG) were developed. Although typically increased in CD, these antibodies are not pathognomonic since they are also detected in several other autoimmune processes. IgA deficiency among celiac patients is more frequent than in general population (up to 25% vs 1-3%). This led to develop kits able to measure IgG-TTG, which until today represent a helpful diagnostic tool during diagnosis of CD in IgA deficient individuals. Today, commercial kits measuring IgG- TTG (and other) antibodies are widely available, are frequently used and create confusion in diagnosing CD in IgA-sufficient individuals. This is attributed to the fact that sensitivity and specificity of IgG-TTG is lower when applied to IgA-sufficient persons, and also because IgG-TTG is detected in several autoimmune disorders, with variable frequency and isotypes depending on the condition. Evidence analyzed indicate that to date available data: i) is insufficient to understand the difference of classes and subclasses detected in CD and other autoimmune conditions; ii) does not support the use of IgG-TTG for diagnosing CD in IgA-sufficient individuals and therefore iii) IgG should not be used in the routine diagnostic process of CD

Living with Gluten and Other Food Intolerances: Self-Reported Diagnoses and Management

People suffering from a food intolerance (FI) tend to initiate restrictive diets such as a gluten-free diet (GFD), to alleviate their symptoms. To learn about how people live with these problems in daily life (independent of their medical diagnoses), 1203 participants answered a previously validated questionnaire and were divided into: G1 (those self-reporting symptoms after gluten consumption) and G2 (those informing no discomfort after gluten consumption). Self-reported clinical characteristics, diagnoses and diets followed were registered. Twenty nine percent referred some FI (8.5% in G1). In G1, self-reported diagnoses were more frequent (p< 0.0001), including a high proportion of eating and mood disorders. Diagnoses were reported to be given by a physician, but GFD was indicated by professional and nonprofessional persons. In G2, despite declaring no symptoms after gluten consumption, 11.1% followed a GFD. The most frequent answer in both groups was that GFD was followed "to care for my health", suggesting that some celiac patients do not acknowledge it as treatment. Conclusion: close to one third of the population report suffering from some FI. Those perceiving themselves as gluten intolerant report more diseases (p< 0.0001). A GFD is followed by similar to 11% of those declaring no symptoms after gluten ingestion. This diet is perceived as a healthy eating option.Consejo Nacional de Ciencia y Tecnología (CONACyT