Lab Test

Endomysial Antibody, IgA

Dermatitis Herpetiformis, Celiac Disease, Tropical Sprue

Test Codes

EPIC: LAB5755, SOFT: ENDOA

Department

Special Chemistry

Specimen Collection Criteria

Collect: One Gold-top SST tube. (Minimum Whole Blood: 2.0 mL)

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged collection tube within two hours of collection. (Minimum Serum: 0.5 mL)

Preparation for Courier Transport

Transport: Centrifuged collection tube, refrigerated (2-8 °C or 36-46 °F). (Minimum Serum: 0.5 mL)

Rejection Criteria

Plasma specimens.

Severely hemolyzed, lipemic or icteric specimens.

In-Lab Processing

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Room temperature is acceptable for a maximum of two hours. (Minimum Serum: 0.5 mL)

Storage

Specimen Stability for Testing:

Centrifuged SST Tubes and Microtainers® with Separator Gels
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable

Red-top Tubes and Microtainers® without Separator Gels
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Serum Specimens (Pour-Overs)
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 3 months

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 7 days

Laboratory

Royal Oak Special Testing Laboratory

Performed

Tuesday.
Results available the same day as testing performed.

Reference Range

Less than 1:5.

Test Methodology

Indirect Immunofluorescence Assay (IFA).

Interpretation

  • IgA-endomysial antibody (IgA-EMA) is highly specific for celiac disease or dermatitis herpetiformis. Seventy to eighty percent of patients with celiac disease or dermatitis herpetiformis have circulating IgA-EMA.
  • Titer values generally correlate with the severity of gluten-sensitive enteropathy.
  • IgA-EMA titer values should begin to decrease within 6-12 months if patients strictly adhere to a gluten-free diet.

Clinical Utility

  • Endomysial antibodies are useful to screen high-risk populations (e.g. first degree relatives of celiac patients, insulin dependent diabetics, etc.) for celiac disease. However, histologic confirmation is required for diagnosis. Patients should not begin a gluten-free diet until after intestinal biopsy has been performed and the diagnosis is established. Serial celiac antibody titers may at times be useful to monitor dietary compliance.
  • Patients with IgA deficiency may have falsely negative test results. If there is a high degree of suspicion for celiac disease in a patient with IgA deficiency, tissue transglutaminase antibodies (IgG) level should be requested.

CPT Codes

86255
LOINC: 27038-9

Contacts

Last Updated

1/11/2023

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