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GI/Nutrition > Celiac's Disease > Flashcards

Flashcards in Celiac's Disease Deck (29)
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1
Q

What does the body lose tolerance to?
How is this substance processed in the gut?

A

Increased levels of de-amidated gliadin peptide
Gluten is comprised of gliadin
Gliadin converted to de-amidated gliadin by tissue transglutaminase once passage across the mucosa

2
Q

What genetic predisposition towards autoimmunity is there?
What antibodies are produced?

A

HLA-DQ2 (95% have heterodimer) & HLA-DQ8 (5% have heterodimer) genes
Tissue transglutaminase, endomysium, gliadin peptide antibodies

3
Q

What type of hypersensitivity reaction is involved?
What is the mechanism involved?

A

Type IV
Th1 increases IFNg which induces IgA and IgG plasma cells
Macrophage and PMN invasion

4
Q

What are the signs of classic Celiac’s?
Is this representative?

A

Diarrhea, bloating, abdominal pain, weight loss
Possible growth retardation, failure to thrive
Actually atypical

5
Q

What are the levels of CD?
What signs does each show?

A

Latent and healthy - Lack of antibodies
Silent celiac sprue - Show mucosal abnormalities
Atypical celiac sprue
Classic celiac sprue

6
Q

Who is likely to have silent celiac sprue?
What is the risk for them?

A

Relative of Sprue patient
May be susceptible of progressing

7
Q

What are the major symptoms of atypical celiac sprue?

A

Iron deficiency
Osteoporosis
Dermatitis Herpetiformis
IBS
T1DM
Elevated LFTs (idiopathic)

8
Q

What is the prelavence of CD?
What are the risks for relatives?

A

1 in 100 northern European descent

Iron deficiency
Osteoporosis
Dermatitis Herpetiformis
IBS
T1DM
Elevated LFTs (idiopathic)

9
Q

Where does CD affect in the GI?

A

Can affect any part of the intestine
Primarily occurs at duodenum – Highest exposure of gluten

10
Q

What GI/nutrient related atypical issues can result from CD?

A

Unexplained iron-deficiency anemia (3 to 15%)
Folic acid or B12 deficiency
Reduced serum albumin
Unexplained Elevated LFTs

11
Q

What autoimmune disorders are related to CD?
What genetic syndromes?
What immunodeficiency?

A

T1DM
Thyroid dysfunction
Addison’s
PBC
Sjogren’s Disease
Autoimmune Hepatitis

Down syndrome and Turner Syndrome (6-14%)

Selective IgA deficiency

12
Q

What is dermatis herpetiformis?
How is it treated?

A

Pruritic, papulovesicles
Extensor surface of the extremities on the trunk
Regardless of cause, treated with gluten elimination

13
Q

What is the most common non-GI presentation of CD?
What should all newly diagnosed CD patients have?
Should those with this presentation be screened for CD?

A

Bone Diseases (Osteopenia/Osteoporosis)
Bone Scan
Controversial

14
Q

What neurologic symptoms do CD patients have?
Why?

A

Ataxia
Night blindness
Seizures
Headaches
Epilepsy
Mood disturbances
Peripheral neuropathies

Vitamin Malnutrition

15
Q

What gynecologic and fertility problems are there wtih CD?

A

Amenorrhea 1/3 untreated CD
Female infertility common in untreated CD- Common to become pregnant shortly after commencing a GFD
Spontaneous abortions
Intrauterine fetal growth retardation
Male infertility reported (rarer)

16
Q

What are the most useful tests for CD?
How about Anti-Gliadin Antibodies?
How about general IgA?

A

IgA Endomysial antibody (EMA)
IgA Tissue Transglutaminase (tTG)
IgA and IgG Deamidated Gliadin Antibodies

Little value, “CRP of the gut”

IgA Level – Technically not recommended for screening

17
Q

What are the causes of false negatives in serology?
How can each be addressed?

A

Ab levels fall on a gluten-free diet
Within days in very mild disease
Usually takes 6-8 weeks
AS long as a year in severe disease

Celiac patient that is IgA deficient
IgG Abs useful in this situation
IgG deamidated Gliadin
Biopsy

18
Q

What is seen on the small intestine biopsy of CD?
When is it done?
How many should be taken?

A

“Scalloping” or “Notching” of the small bowel folds
Small intestinal villous atrophy
Increase of intraepithelial lymphocytes
Crypt hyperplasia

Following positive serology

Multiple biopsies should be obtained – Total of 6 to 8

19
Q

What issues are there with biopsies?

A

Villous atrophy can be patchy
Were enough biopsies taken?
Should we biopsy jejunum and ileum?

Was patient on GFD?
Takes 6 months to normalize
May never normalize in adults

Not all Villous Atrophy is Celiac
NSAIDs
Infections
IBD

20
Q

What is the problem with genetic testing?
When is it useful?

A

40% of European ancestry are DQ2 or DQ8 positive

Most helpful in ruling out Celiac Disease
Useful for patients who want off a GFD

21
Q

How do you treat CD?

A

Gluten Free Diet

22
Q

What are the major things that need to be avoided on a GFD?

A

Avoid all food containing wheat rye and barley gluten
Avoid malt
Read all labels
Beware of gluten in medications

23
Q

What are the down-sides of a GFD?

A

Not much
Iron, Calcium, Vitamin D, and B Vitamin deficiencies - Use a multivitamin
GFD is low fiber – Watch for constipation
Replacement with sugary foods, simple carbohydrates
Difficult to eat out/Social Stigma
Costly/Inability to maintain for long term if not necessary

24
Q

Should asymptomatic individuals be treated with GFD?
What can it affect?

A

Four fold increase in all-cause mortality if untreated

Often CVD and malignancy likely normalized with GFD
Less likely to get Enteropathy Associated T-cell Lymphoma
Osteoporosis – Improvement on GFD
IDA – Improvement on GFD
Rashes improved
Avoid development of other autoimmune diseases
Improves fertility

25
Q

What is enteropathy associated T-cell lymphoma?
How is survival?
What is the CD associated risk?

A

Malignant Complication
High-grade T-cell NHL
5 year survival rate ~10%
Occurs ~20x more frequently in patients with CD
Normalized risk with GFD

26
Q

Where does wheat allergy affect?
What kind of disease it and what are the different types of it?
What is the prevalence?
What is the serology?
What is the biopsy?
How is it diagnosed?

A

Classic food allergy affecting Skin, GI, Respiratory tract

IgE Mediated Diseases
Baker’s asthma
Rhinitis
Contact urticarial
Wheat-dependent, exercise-induced anaphylaxis

Prevalence is about 0.5 to 2%
True anaphylaxis is rare

Normal antibodies

Normal intestinal mucosa

Diagnosis made by allergy pin prick testing

27
Q

What is non-celiac gluten sensitivity?
How many people have tried a GFD?
Is this a fad?
Is it real?
What are the genetics?
Is there enteropathy?

A

Patients who claim symptoms feel better on a GFD
17 million people have tried a GFD
Patient driven and likely to stay - Massive growth of the gluten free diet
Literature is unclear but evidence appears to be growing that it is a real phenomenon
Not restricted to HLA-DQ2 or HLA-DQ8
Enteropathy – Almost always absent

28
Q

Why do patients feel better?

A

Change in dietary intake: Lower carbs, more fruits and veggies, arguably “healthier” choices

Fermentable fructans may cause symptoms
Fermentation and gas production by gut microbiota
Reduction of gluten may inadvertently be reducing the ingestion of fructans

Withdrawal of fermentable oligosaccharides, disaccharides, monosaccharides which play a role in IBS

29
Q

What is environemental enteropathy/tropical sprue?
Where does it affect?
Who does it affect?
What is the process of pathogenesis?
How does it manifest?
What is the histology?

  • *Very Unlikely to be Tested On**
  • *Just Added For Completeness**
A

Syndrome of stunted growth and diarrhea

Developing world

Affects > 150 million children worldwide

Malnutrition thought to make susceptible to pathogenesis
Thought to be reversible if fed/nutrition restored
Recurrent diarrhea establishes a cycle of mucosal injury, malnutrition, infection, inflammation
Repeated bouts of diarrhea within 2 or 3 years of life

No single infectious agent

Histiologic features similar to severe celiac disease