From the Guidelines
A tissue transglutaminase (tTG) level of 52 in a six-year-old child is elevated and strongly suggests celiac disease, necessitating referral to a pediatric gastroenterologist for further evaluation, including possible intestinal biopsy to confirm the diagnosis, as recommended by recent guidelines 1. The normal range for tTG antibodies is typically below 20 U/mL, with levels above 20 considered positive. At 52, this is a moderately high positive result, indicating a significant immune response to gluten. While awaiting specialist consultation, parents should not remove gluten from the child's diet yet, as this could interfere with diagnostic testing, such as intestinal biopsy, which is crucial for confirming the diagnosis of celiac disease 1. Celiac disease is an autoimmune condition where gluten consumption triggers the immune system to produce antibodies like tTG that damage the small intestine. These elevated antibodies indicate the body is reacting to gluten proteins found in wheat, barley, and rye. Key considerations in managing this condition include:
- Early diagnosis and treatment to prevent complications like growth problems, nutrient deficiencies, and intestinal damage in children 1
- The importance of a strict, lifelong gluten-free diet if celiac disease is confirmed, which can reduce symptoms and rates of hypoglycemia in symptomatic children with type 1 diabetes and confirmed celiac disease 1
- The potential burden of dietary restrictions associated with having both type 1 diabetes and celiac disease, emphasizing the need for a confirmed diagnosis before prescribing significant dietary changes 1
From the Research
Elevated Tissue Transglutaminase (tTG) Levels in Children
Elevated tissue transglutaminase (tTG) levels, such as 52, in a six-year-old child may indicate a potential issue with celiac disease. The following points summarize the significance of elevated tTG levels:
- Celiac disease is an immune-mediated enteropathy caused by a permanent sensitivity to gluten in genetically susceptible individuals, and elevated tTG levels can be an indicator of this condition 2.
- The Celiac Disease Guideline Committee recommends that children and adolescents with symptoms of celiac disease or an increased risk for celiac disease have a blood test for antibody to tissue transglutaminase (TTG) 2.
- However, high titers of tissue transglutaminase are not sufficient to diagnose celiac disease in North American children without intestinal biopsies, as the positive predictive value of tissue transglutaminase titers at ≥10× upper limit of normal was 87.7% 3.
- Immunoglobulin A (IgA) tTG antibodies have high sensitivity and specificity in the diagnosis of celiac disease in children, and high titers of IgA tTG antibodies are correlated with intestinal mucosal lesions 4.
Diagnostic Approach
The diagnostic approach for celiac disease in children with elevated tTG levels includes:
- Blood tests for antibody to tissue transglutaminase (TTG) 2.
- Intestinal biopsy to confirm the diagnosis of celiac disease 2, 3.
- Consideration of other serological tests, such as deamidated gliadin peptide (DGP) tests, although these may have limited predictive value in children with normal tTG levels 5.
Role of Tissue Transglutaminase in Celiac Disease
Tissue transglutaminase (tTG) plays a crucial role in the pathogenesis of celiac disease, including: