Why does celiac disease develop in adults?

From the Guidelines

Celiac disease can develop in adults due to a combination of genetic predisposition and environmental triggers, with the presence of HLA-DQ2 and/or HLA-DQ8 molecules being a crucial factor, as nearly 100% of individuals diagnosed with celiac disease exhibit this specific genetic profile 1. The disease involves an autoimmune reaction where the body mistakenly attacks the small intestine when gluten is consumed, leading to villous atrophy, intra-epithelial lymphocytosis, and crypt hyperplasia of the small bowel 1. Some key points to consider include:

• Genetic susceptibility, particularly HLA-DQ2 and HLA-DQ8, plays a significant role in the development of celiac disease in adults 1
• Environmental triggers such as significant life stressors, viral infections, pregnancy, childbirth, surgery, or other major health events can activate the immune response and lead to the development of celiac disease in adults
• Repeated gluten exposure over time can gradually damage the intestinal lining until symptoms become noticeable
• The only effective treatment is a strict, lifelong gluten-free diet to prevent intestinal damage and related complications
• Diagnosis of celiac disease in adulthood is based on serology, such as testing for anti-type 2 transglutaminase antibodies (TG2Ab), and duodenal biopsy while the patient is on a gluten-containing diet, with high sensitivity and specificity 1. The development of celiac disease in adults is a complex process, and a definitive diagnosis requires evidence of compatible small bowel damage, which can be confirmed through endoscopy with multiple bulb and distal duodenal biopsies, and histological evaluation of the villous to crypt cell ratio in well-oriented biopsy specimens 1.

From the Research

Celiac Disease Development in Adults

• Celiac disease is a chronic and systemic autoimmune condition triggered by gluten ingestion in genetically predisposed subjects 2.
• The clinical presentation of celiac disease is highly variable and ranges from malabsorption through solely extra-intestinal manifestations to asymptomatic, making it challenging to diagnose 3.
• The only effective treatment for celiac disease is a lifelong, strict, gluten-free diet, but many barriers impede patients' adherence to this diet, including lack of widespread availability, high cost, cross-contamination, and its overall restrictive nature 3.

Factors Associated with Celiac Disease Development in Adults

• Younger age at the time of diagnosis and smoking were significantly associated with non-adherence to a gluten-free diet in adult celiac disease patients 4.
• Other factors such as longer duration of disease, non-academic education, below average income, and no gastroenterology follow-up were associated with low adherence to a gluten-free diet in univariate analysis, but not in multivariate analysis 4.
• The variability in histological grading and in the diagnostic performance of some commercially available serological tests remains unacceptably high, and confirmatory assays are not readily available in many parts of the world, making diagnosis and management of celiac disease challenging 3.

Therapeutic Options for Celiac Disease

• Currently, the only proven treatment for celiac disease is adherence to a strict, lifelong, gluten-free diet, but complete dietary gluten avoidance is challenging, and a substantial number of patients do not respond fully, clinically, or histologically, despite their best efforts 5.
• Several therapeutic approaches are being developed to address the limitations of dietary treatment, including decreasing gluten immunogenic content, sequestering gluten in the gut lumen, blocking the passage of gluten through a leaky intestinal barrier, preventing the enhancement of immune response against gliadin, dampening the downstream immune activation, and inducing immune tolerance to gluten 2.