Celiac Flashcards
What characterizes celiac disease?
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A: Intestinal hypersensitivity to gluten
What is gluten?
A: A group of proteins, including gliadins and glutelins, found in wheat, barley, and rye.
What is the peak age of onset for celiac disease?
A: 8–12 months, third to fourth decade of life, and 5th decade.
Which HLA antigens are associated with celiac disease?
A: HLA-DQ2 (90–95%) and HLA-DQ8 (5–10%).
- Q: What triggers the autoimmune reaction in celiac disease?
A: Gliadin from gluten-containing grains like wheat, rye, and barley.
What happens to the intestinal lining in celiac disease?
A: Chronic inflammation causes villous atrophy, crypt hyperplasia, and nutrient malabsorption.
What enzyme modifies gliadin in celiac disease?
A: Tissue transglutaminase.
What is classical celiac disease?
A: Celiac disease with symptoms like diarrhea, steatorrhea, and weight loss.
What is asymptomatic celiac disease?
A: Identified by serology and villous atrophy without symptoms.
Define refractory celiac disease (RCD).
A: Symptoms persist despite a gluten-free diet.
What are common gastrointestinal symptoms?
A: Chronic diarrhea, steatorrhea, abdominal pain, and bloating.
Name an associated dermatologic condition.
A: Dermatitis herpetiformis.
What are extraintestinal manifestations in children?
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A: Growth failure and delayed puberty
What is the first-line serologic test for celiac disease?
A: IgA tissue transglutaminase antibody (tTG IgA).
What histological features confirm celiac disease?
A: Villous atrophy and crypt hyperplasia.
What test is performed if IgA deficiency is suspected?
A: IgG-based tests like deamidated gliadin peptide (DGP).
What is the Marsh classification used for?
A: Ranking histological severity in celiac disease.
When is HLA testing useful?
A: For uncertain cases or patients on a gluten-free diet.
What is the main treatment for celiac disease?
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A: Lifelong gluten-free diet
Why might lactose intolerance occur in celiac disease?
A: Secondary lactase deficiency due to mucosal damage.
What supplements might be necessary for celiac patients?
A: Iron, folic acid, calcium, vitamin D, and B12.
Name a malignancy associated with celiac disease.
A: Enteropathy-associated T-cell lymphoma (EATL).
What causes refractory celiac disease type 2 (RCD2)?
A: Semi-malignant inflammatory conditions.
Name a rare associated disorder in refractory celiac disease.
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A: Collagenous sprue
How soon do symptoms improve on a gluten-free diet?
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A: Within two weeks for most patients
When should follow-up blood tests be performed?
A: At 3–6 months, 12 months, and annually.
Which antibodies are monitored for compliance?
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A: IgA tTG or IgA (or IgG) DGP
Name an endocrine association with celiac disease.
A: Autoimmune thyroid disease or type 1 diabetes.
Which chromosomal syndromes are associated?
A: Turner syndrome and Down syndrome.
Name a neuropsychiatric symptom of celiac disease.
A: Peripheral neuropathy or depression.
Define latent celiac disease.
A: Positive serology but normal small intestine biopsy.
What is nonceliac gluten sensitivity?
A: Symptoms triggered by gluten without celiac disease.
Q: What is the hallmark of dermatitis herpetiformis?
A: Pruritic vesiculo-papular eruptions on extensor surfaces.
How many biopsies should be taken for celiac diagnosis?
A: At least five, including one from the duodenal bulb.
What can mimic villous atrophy on biopsy?
A: Bacterial overgrowth, tropical sprue, or giardiasis.
Which cells mediate inflammation in celiac disease?
A: Pathogenic T cells.
What part of the small intestine is most affected in celiac disease?
A: The distal duodenum and proximal jejunum.
What role does tissue transglutaminase (tTG) play in celiac disease?
A: It modifies gliadin, making it antigenic.
Why is total IgA testing recommended in celiac disease?
A: To detect IgA deficiency, which may affect antibody test accuracy.
- Q: What is the specificity of the tTG IgA test?
A: ≥ 96%.
Why is antigliadin antibody testing no longer commonly used?
A: It is sensitive but not specific.
What is the role of anti-endomysial antibody (EMA) testing?
A: A second-line confirmatory test due to its high specificity.
What does intraepithelial lymphocytosis indicate in a biopsy?
A: Early or mild celiac disease.
What compensates for villous atrophy in celiac disease?
A: Crypt hyperplasia.
What chronic inflammatory changes occur in the lamina propria?
A: Lymphocytic and plasma cell infiltration.
What nutritional deficiencies are common in celiac disease?
A: Iron, calcium, vitamin D, folate, and vitamin B12.
What is ulcerative jejunoileitis?
A: A severe complication causing inflammation and ulceration of the small intestine.
What is microscopic colitis, and how is it related?
A: An associated condition causing watery diarrhea.
Q: Name a condition that mimics celiac disease symptoms.
A: Irritable bowel syndrome (IBS).
How does hypogammaglobulinemic sprue differ from celiac disease?
A: It is associated with immunodeficiency rather than gluten sensitivity.
What parasitic infection can mimic celiac histology?
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A: Giardiasis
Why is a gluten challenge sometimes necessary?
A: To confirm diagnosis in patients already on a gluten-free diet.
What should be checked during follow-up for celiac disease?
A: Complete blood count, iron studies, folate, B12, and liver chemistries.
When is repeat biopsy recommended?
A: After two years on a gluten-free diet to assess mucosal healing.
What indicates non-compliance with a gluten-free diet?
A: Persistently positive serologic tests.
- Q: What is RCD1?
A: Refractory celiac disease type 1, caused by high sensitivity to minimal gluten exposure.
Q: What serious condition is associated with RCD2?
A: Enteropathy-associated T-cell lymphoma (EATL).
What grains must celiac patients avoid?
A: Wheat, rye, barley, and spelt.
What is secondary lactase deficiency?
A: Temporary lactose intolerance due to damaged intestinal mucosa.
Why is vitamin D supplementation often necessary?
A: To address osteoporosis and hypocalcemia.
What percentage of dermatitis herpetiformis patients have characteristic intestinal biopsy findings?
A: 85%.
Where does dermatitis herpetiformis typically appear?
A: On the face, trunk, buttocks, sacrum, elbows, and knees.
Which autoimmune diseases are often associated with celiac disease?
A: Type 1 diabetes mellitus and autoimmune thyroid disease.
What is the relationship between celiac disease and selective IgA deficiency?
A: Celiac patients have a higher prevalence of IgA deficiency.
What is autoimmune hepatitis, and how is it related?
A: A liver condition associated with celiac disease.
What is the prognosis for patients adhering to a gluten-free diet?
A: Generally excellent, with reduced risk of complications and malignancies.
