Celiac Disease

Key Features

Essentials of Diagnosis

• Typical symptoms

  • Weight loss

  • Chronic diarrhea

  • Abdominal distention

  • Growth retardation

• Atypical symptoms

  • Dermatitis herpetiformis

  • Iron deficiency anemia

  • Osteoporosis

• Abnormal serologic test results

• Abnormal small bowel biopsy

• Clinical improvement on gluten-free diet

General Considerations

• Caused by an immunologic response to gluten that results in diffuse damage to the proximal small intestinal mucosa with malabsorption of nutrients

• Gluten is a storage protein found in certain grains that is partially digested in the intestinal lumen into glutamine-rich peptides

• Most cases of celiac disease present in childhood or adulthood, although symptoms may manifest in infancy (between 6 and 24 months of age)

Demographics

• Global prevalence is 1.4%

• In North America, the prevalence of biopsy-confirmed disease is 0.5%

Clinical Findings

Symptoms and Signs

• "Classic" symptoms of malabsorption more commonly present in infants (< 2 years)

  • Diarrhea

  • Steatorrhea

  • Weight loss

  • Abdominal distention

  • Weakness

  • Muscle wasting

  • Growth retardation

• Older children and adults are less likely to manifest signs of serious malabsorption but may report

  • Chronic diarrhea

  • Dyspepsia

  • Flatulence

  • Variable weight loss

• Many adults have minimal or no gastrointestinal symptoms but present with extraintestinal "atypical" manifestations

  • Fatigue

  • Depression

  • Iron-deficiency anemia

  • Osteoporosis

  • Short stature

  • Delayed puberty

  • Amenorrhea or reduced fertility

• Physical examination

  • In mild cases: may be normal

  • In more severe cases: may reveal signs of malabsorption, loss of muscle mass or subcutaneous fat, pallor, easy bruising, hyperkeratosis, or bone pain

• Abdominal examination may reveal distention with hyperactive bowel sounds

• Dermatitis herpetiformis in < 10%

Differential Diagnosis

• Irritable bowel syndrome

• Malabsorption due to other causes

• Lactase deficiency

• Viral gastroenteritis, eosinophilic gastroenteritis

• Whipple disease

• Giardiasis

• Mucosal damage caused by acid hypersecretion associated with gastrinoma

• Non-celiac gluten sensitivity

  • Frequency and cause of this entity is debated

  • Blinded clinical trials suggest that self-reported wheat sensitivity is not due to gluten intolerance and that the symptom improvement reported by patients with gluten restriction is due to broader FODMAP elimination

Diagnosis

Laboratory Tests

• Obtain complete blood count, prothrombin time, serum albumin, iron or ferritin, calcium, alkaline phosphatase, red cell folate, vitamins B₁₂, A, and D levels

• Iron deficiency or megaloblastic anemia occurs because of iron or folate or vitamin B₁₂ malabsorption

• Elevation of prothrombin time due to vitamin K deficiency

• Other deficiencies may include zinc and vitamin B₆

• Serologic tests should be performed in all patients

  • IgA tissue transglutaminase (IgA tTG) antibody is recommended; has a 95% sensitivity and 95% specificity for detecting celiac disease

  • Antigliadin antibodies are not recommended because of their lower sensitivity and specificity

  • IgA antiendomysial antibodies are no longer recommended due to the lack of standardization among ...