Celiac Disease

Gastroenterology / Autoimmune

Overview

Definition

An immune-mediated enteropathy triggered by the ingestion of gluten in genetically susceptible individuals.

Epidemiology

Affects ~1% of the population. Associated with HLA-DQ2 and HLA-DQ8.

Etiology & Risk Factors

  • Autoimmune reaction to gliadin (a component of gluten found in wheat, barley, and rye)
  • Tissue transglutaminase (tTG) modifies gliadin, causing T-cells to attack the small intestine mucosa (specifically the duodenum).

Clinical Symptoms

  • Chronic diarrhea, steatorrhea (foul-smelling, fatty stools)
  • Weight loss and failure to thrive (in children)
  • Flatulence, bloating, abdominal pain
  • Dermatitis Herpetiformis (pruritic, vesicular rash on extensor surfaces - knees, elbows, buttocks)
  • Anemia (Iron, B12, or Folate deficiency)

Clinical Approach

Diagnosis

  • Serology: IgA anti-tissue transglutaminase (tTG) antibodies (highly sensitive/specific). MUST check total IgA levels as IgA deficiency is common in Celiac (would cause a false negative tTG)
  • Endoscopy with Duodenal Biopsy (Gold Standard): Villous atrophy, crypt hyperplasia, intraepithelial lymphocytosis
  • Note: Testing MUST be done while the patient is still consuming gluten

Management

  • Strict, lifelong adherence to a gluten-free diet (avoid wheat, barley, rye)
  • Oats are generally safe but may be cross-contaminated
  • Vitamin and mineral supplementation (Iron, Calcium, Vitamin D, B12)

Complications

  • Osteoporosis (due to calcium/Vitamin D malabsorption)
  • Enteropathy-associated T-cell lymphoma (EATL)
  • Increased risk of other autoimmune diseases (Type 1 Diabetes, Autoimmune Thyroiditis)