[Anti-tissue transglutaminase antibodies not related to gluten intake]

Abstract

Introduction: Anti-tissue transglutaminase antibodies (tTG) have high specificity for coeliac disease (CD). However, positive anti-tTG antibodies have been described in non-coeliac patients. Aim To assess positive anti-tTG antibodies not related to gluten intake.

Patients and methods: Retrospective review and follow up conducted on patients with suspected CD (increase anti-tTG levels and gastrointestinal symptoms) but with atypical serology results, positive anti-tTG with gluten free diet and a decrease in anti-tTG levels despite gluten intake.

Results: A total of 9 cases were reviewed in which 5 cases had Marsh 3 involvement in the initial biopsy, and were diagnosed with CD (Group A). They began a gluten free diet and also a cow's milk protein (CMP) free diet because of their nutritional status. When CMP was re-introduced, anti-tTG increased, and returned to normal after the CMP was withdrawn again. The other 4 patients had a normal initial biopsy (Group B). Gluten was not removed from their diet, but they started a CMP free diet because a non IgE mediated CMP allergy was suspected. Symptoms disappeared, and anti-tTG was normal after CMP free diet with gluten intake. All the patients had susceptibility haplotype HLA DQ2/DQ8.

Conclusions: CMP ingestion after an exclusion diet can induce an increase in anti-tTG in some coeliac subjects. CMP can produce this immune response if there were no gluten transgressions. This response has also been observed in non-IgE mediated CMP allergy patients with the susceptibility haplotype HLA DQ2/DQ8.

Keywords: Anti-transglutaminase antibodies; Anticuerpos antitransglutaminasa; Bovine casein; Caseína bovina; Coeliac disease; Coẃs milk protein; Enfermedad celíaca; Gluten; Proteínas de leche de vaca.