Celiac Disease

Excerpt

Clinical characteristics: Celiac disease is a systemic autoimmune disease that can be associated with gastrointestinal findings (diarrhea, malabsorption, abdominal pain and distension, bloating, vomiting, and weight loss) and/or highly variable non-gastrointestinal findings (dermatitis herpetiformis, chronic fatigue, joint pain/inflammation, iron deficiency anemia, migraines, depression, attention-deficit disorder, epilepsy, osteoporosis/osteopenia, infertility and/or recurrent fetal loss, vitamin deficiencies, short stature, failure to thrive, delayed puberty, dental enamel defects, and autoimmune disorders). Classic celiac disease, characterized by mild to severe gastrointestinal symptoms, is less common than non-classic celiac disease, characterized by absence of gastrointestinal symptoms.

Diagnosis/testing: The diagnosis of celiac disease is established in an individual with:

1. Positive celiac serologic testing while on a gluten-containing diet (tissue transglutaminase IgA, anti-deamidated gliadin-related peptide IgA and IgG, endomysial antibody IgA),

2. Characteristic histologic findings on small-bowel biopsy, and

3. Human leukocyte antigen (HLA) haplotype DQ2 or DQ8 identified by molecular genetic testing of HLA-DQA1 and HLA-DQB1.

Management: Treatment of manifestations: Lifelong adherence to a strict gluten-free diet (avoidance of wheat, rye, and barley); treatment of nutritional deficiencies (iron, zinc, calcium, fat-soluble vitamins, folic acid); standard treatment of osteoporosis. For individuals unresponsive to a gluten-free diet, evaluation for refractory celiac disease, ulcerative enteritis, T-cell lymphoma, and other gastrointestinal cancers.

Surveillance: For symptomatic individuals responsive to a gluten-free diet abnormal serologies should be followed to normalization, periodic physical examination and assessment of growth, nutritional status, and non-gastrointestinal disease manifestations.

Agents/circumstances to avoid: Dietary gluten.

Evaluation of relatives at risk: Molecular genetic testing of first-degree relatives of a proband (including young children) to monitor those with known celiac disease-susceptibility alleles for early evidence of celiac disease in order to institute gluten-free diet early in the disease course.

Genetic counseling: Celiac disease is a multifactorial disorder resulting from the interaction of HLA-DQA1 and HLA-DQB1 allelic variants known to be associated with celiac disease susceptibility, less well-recognized variants in non-HLA genes, gliadin (a subcomponent of gluten), and other environmental factors. Some empiric risk data for at-risk relatives are available.