Celiac Disease

last authored: March 2013, Dave LaPierre
last reviewed:

 

 

Introduction

Celiac disease, or 'gluten-sensitive enteropathy', is an allergy to the protein gluten found in wheat, barley, rye, and other grains.

Inherited, autoimmune, inflammatory enteropathy

It has an incidence of 1:80-140 in children of European descent. It usually presents at 6-18 months as wheat is introduced into the diet, but can occur at any age.

There is a delay in diagnosis of 4 years in the United States.

 

Prevalence as evidenced by screening is approximately 1:300, while the average prevalence on clinical diagosis is 1:3000.

 

Clinicians and patients are also increasingly aware of the condition of gluten intolerance.

Celiac disease tends to be diagnosed by gastroenterologists.

 

Diagnostic criteria are as follows:

 

There is a spectrum of celiac disease

classical (childhood): diarrhea, bloating, failure to thrive

late-onset (adult)

extra-intestinal: anemia, osteoporosis, autoimmune disease

silent: asymptomatic, but positive antibodies and abnormal biopsy

latent: positive serology, but negative biopsy

atypical

 

The Case of Sam R.

Sam is a 34 year-old man who has been experiencing increasing abdominal cramping and diarrhea.

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Causes and Risk Factors

Ethnicity plays a major role in epidemiology

Family history leads to a prevalence of 8-10% amongst first degree relatives.

Other conditions that can be associated with celiac disease include:

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Pathophysiology

Whole wheat grain is composed of bran, germ, and endosperm, which contains complex carbohydrates, B-complex vitamins, and proteins. These proteins include gliadin and glutelin.

 

Possible wheat reactions include:

Maldigestion of grain constituents, leading to sumptoms of excess fluid and gas.

IgE-mediated allergy to one of the components, leading to nause and atopic symptoms.

Cell-mediated immunity to gluten (gliadin), leading to small bowel mucosal injury.

 

 

Allergy to gluten causes immune-mediated inflammation and destruction of absorptive villi.

 

There are a variety of steps in the pathophysiology of celiac disease:

IgA is not the offending antibody.

Classic celiac disease is initiated by poorly digested proline with glutamine (gliadin). This is normally deaminated by tissue transglutaminase. This leads to generation of negatively charged..

 

TTG is found in other tissues as well, leading to other clinical manifestations.

 

Neurological:

Cardiomyopathy

Hepatitis, cholangitis

Osteoporosis, fractures

Short stature

Arthritis

Dental abnormalities

Digestive

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Signs and Symptoms

Diarrhea is the predominant symptom in less than half of people diagnosed; and many patients have a delay in diagnosis by many years.

  • history
  • physical exam

History

Classical symptoms include:

  • failure to thrive in infants and children
  • fatigue, irritability
  • non-bloody diarrhea, steatorrhea
  • nausea, vomiting, abdominal pain
  • edema
  • weight loss
  • gas and bloating

 

Atypical

Physical Exam

Wasted muscles, distended abdomen, flatt buttocks

clubbing

rickets

 

non-GI manifestations (edit this list)

neuropsychoatric disorders - depression, psychosis

arthritis

osteoporosis

hyposplenism

dermititis herpetiformis

diabtetes

IgA deficiency

Down's syndrome

liver disease

thyroid disease

 

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Investigations

  • lab investigations
  • diagnostic imaging

Lab Investigations

anemia can be present

 

Screening and diagnostic tests should be done while the patient is eating gluten, eg 2-4 pieces of bread daily for 4 weeks.

tissue transglutaminase (tTG) (95% sensitivity and 98% specificity)

  • if the test is positive, refer the patient for small bowel biopsy

The AGA suggests screening for the following groups

 

Up to 1/50 patients with CD are IgA deficient; this can result in false negative testing. IgA should be ordered.

IgG antibodies may be investigated as well.

IgE testing with prick or patch testing (especially if atopic symptoms are present).

other antibodies: antigladin, antiendomyseal

fat malabsorption studies

small bowel biopsy (scope and 4-6 biopsies)

HLA typing: DQ2 and DQ8 positive.

Diagnostic Imaging

 

Endoscopy is required for definitive diagosis.

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Differential Diagnosis

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Treatments

 

Consultation with a skilled dietitian

Education about the disease

Lifelong adherence to gluten-free diet

I

A

C

Diet modification

Wheat, rye and barley must be avoided.

Oats must be avoided if they are not purified.

and perhaps oats must be avoided, for life in some cases.

inadvertent contamination can be a big problem

A gluten-free diet has been estimated to cost over 800 extra yearly (Atkinson et al, 1997).

If sensitivity to wheat products are suspected, without celiac disease, dietary strategies can include dietary enzymes and probiotics.

 

 

address nutritional deficiencies

iron, B12

in severe cases, calcium, magnesium, and electrolytes

 

 

monitor response

role of tTG screening is not known

biopsy should be repeated in 6-12 months

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Consequences and Course

Between 7-30% of patients do not respond to a gluten-free diet. Causes can include:

 

Complications include:

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Resources and References

CeliacStories.ca

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Topic Development

authors:

reviewers:

 

 

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