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Protocol - Celiac Sprue - Assay

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Description:

This protocol uses two-step serologic testing of serum to determine the presence of antihuman recombinant tissue transglutaminase (TTG) and endomysial antibody (EMA). When both tests are positive, the subject is notified that they are positive for celiac sprue. The test is most accurate if patients have not been on a gluten-free diet in the weeks leading up to the assay, as a gluten-free diet may cause the serologic assays to normalize in many patients.

Protocol:

Exclusion Criteria

Persons will be excluded from this component if they:

  • report that they have hemophilia, or
  • report that they have received cancer chemotherapy in the last 4 weeks.

SP= Sample Person.

1. Do you have hemophilia?

[ ] 1 Yes

[ ] 2 No

[ ] 7 Refused

[ ] 9 Don't Know

If the SP answers "Yes," the SP is excluded from the blood draw.

If SP answers "No" or "Don't Know," blood is drawn from the SP.

2. Have you received cancer chemotherapy in the past 4 weeks, or do you anticipate such therapy in the next 4 weeks?

[ ] 1 Yes

[ ] 2 No

[ ] 7 Refused

[ ] 9 Don't Know

If the SP answers "Yes," the SP is excluded from the blood draw.

If SP answers "No" or "Don't Know," blood is drawn from the SP.

Note from the Gastrointestinal WG: The investigator should record the reason a person is excluded from the blood draw.

Venipuncture Procedures

Venipuncture should generally be performed using the median cubital, cephalic, or basilic veins in the left arm unless this arm is unsuitable. If the veins in the left arm are unsuitable, look for suitable veins on the right arm. If the veins in the antecubital space on both arms are not suitable, then look for veins in the forearm or dorsal side of the hand on the left arm/hand and then the right arm/hand.

For a full description of phlebotomy procedures, please refer to Chapter 4 in the downloadable PDF of the 2009–2010 National Health and Nutrition Examination Survey (NHANES) Laboratory Procedures Manual available here: NHANES 2009-2010 Lab Manual

Recording the Results of the Venipuncture Procedure

Immediately after completing the venipuncture, record the results of the blood draw, the reasons for a tube not being drawn according to the protocol, and any comments about the venipuncture.

For a full description of blood processing procedures, please refer to Chapter 8 in the downloadable PDF of the 2009–2010 National Health and Nutrition Examination Survey (NHANES) Laboratory Procedures Manual available here: NHANES 2009-2010 Lab Manual

The serum processing protocol is displayed in Exhibit 8.6.

Laboratory Assay

Note from the Gastrointestinal WG: Although there is not a standardized assay, there are a number of different kits that are appropriate to measure the concentration of TTG and EMA in serum. Once an assay is chosen for a particular study, the WG recommends that no changes in the protocol be made over the course of the study. To aid comparability, the Gastrointestinal WG recommends that the investigator record the make and manufacturer of equipment used and the repeatability and coefficients of variation for the assay.

Reference Intervals

TTG:
19 Units or less = Negative
20–30 Units = Weak Positive
31 Units or greater = Moderate to Strong Positive

EMA: < 1:10

Protocol Name from Source:

This section will be completed when reviewed by an Expert Review Panel.

Availability:

Publicly available

Personnel and Training Required
A laboratory technician or phlebotomist who is trained and found to be competent (i.e., tested by an expert) in the conduct of bioassays.
Equipment Needs
Phlebotomy supplies, laboratory to perform assays
Requirements
Requirement CategoryRequired
Major equipment No
Specialized training No
Specialized requirements for biospecimen collection No
Average time of greater than 15 minutes in an unaffected individual No
Mode of Administration

Bioassay

Life Stage:

Child, Adolescent, Adult

Participants:

Children, adolescents, and adults aged 6 years and older

Specific Instructions:
It is important that the patients screened with this laboratory assay are eating a diet that contains dietary sources of gluten in order for the assay to be most accurate. Sources of dietary gluten include the grains wheat, rye, and barley. The Gastrointestinal Working Group (WG) also recommends performing the immunoglobulin A (IgA) and immunoglobulin G (IgG) antibody tests for more sensitivity. The National Health and Nutrition Examination Survey (NHANES) uses red-top tubes to collect 0.5 ml serum for the antihuman recombinant tissue transglutaminase (TTG)/ endomysial antibody (EMA) bioassay. However, the Gastrointestinal Working Group recommends consulting the laboratory that will perform the bioassay regarding the appropriate collection tubes to use.
Selection Rationale

The National Health and Nutrition Examination Survey (NHANES) 2009-2010 protocol was selected as the best practice methodology and is one of the most widely used research protocols.

Language

English

Standards
StandardNameIDSource
Common Data Elements (CDE) Serum Celiac Disease Assay Laboratory Finding Result 3163027 CDE Browser
Logical Observation Identifiers Names and Codes (LOINC) Celiac sprue assay proto 62957-6 LOINC
Process and Review

This section will be completed when reviewed by an Expert Review Panel.

Source

Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Questionnaire. Laboratory Procedures Manual. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 2009-2010.

General References

Dieterich, W., Ehnis, T., Bauer, M., Donner, P., Volta, U., Riecken, E. O., & Schuppan, D. (1997). Identification of tissue transglutaminase as the autoantigen of celiac disease. National Medicine, 3(7), 797–801.

Dieterich, W., Laag, E., Schopper, H., Volta, U., Ferguson, A., Gillett, H., Riecken, E. O., & Schuppan, D. (1998). Autoantibodies to tissue transglutaminase as predictors of celiac disease. Gastroenterology, 115(6), 1317–1321.

Green, P. H., Rostami, K., & Marsh, M. N. (2005). Diagnosis of coeliac disease. Best Practice and Research Clinical Gastroenterology, 19(3), 389–400.

Protocol ID:

190301

Variables:
Export Variables
Variable NameVariable IDVariable DescriptionVersiondbGaP Mapping
PX190301_Assay_Repeatability_EMA PX190301130000 Repeatability of the assay for endomysial antibody titer 4 N/A
PX190301_Assay_Repeatability_TTG PX190301080000 Repeatability of the assay for tissue transglutaminase antibody 4 N/A
PX190301_Assay_Type_EMA PX190301110000 Record the type of assay used to perform the determination of endomysial antibody titer 4 N/A
PX190301_Assay_Type_TTG PX190301060000 Record the type of assay used to perform the determination of tissue transglutaminase antibody. 4 N/A
PX190301_Blood_Draw_Comments PX190301040300 Record any comments about the blood draw, including any reasons for the tube not being drawn according to the protocol. 4 Variable Mapping
PX190301_Blood_Draw_Done PX190301040100 Was blood drawn? 4 Variable Mapping
PX190301_Blood_Draw_Sample PX190301040200 Was full sample obtained? 4 Variable Mapping
PX190301_Chemotherapy PX190301020000 Have you received cancer chemotherapy in the past four weeks or do you anticipate such therapy in the next four weeks? 4 N/A
PX190301_Coefficient_Of_Variation_EMA PX190301140000 Coefficient of variation for the assay for endomysial antibody titer 4 N/A
PX190301_Coefficient_Of_Variation_TTG PX190301090000 Coefficient of variation for the assay for tissue transglutaminase antibody 4 N/A
PX190301_EMA_Assay_Results PX190301150000 Results of endomysial antibody antibody titer 4 N/A
PX190301_Equipment_Make_EMA PX190301120100 Make of the equipment used to perform the determination of endomysial antibody antibody titer 4 N/A
PX190301_Equipment_Make_TTG PX190301070100 Make of the equipment used to perform the determination of tissue transglutaminase antibody 4 N/A
PX190301_Equipment_Manufacturer_EMA PX190301120200 Manufacturer of the equipment used to perform the determination of endomysial antibody antibody titer 4 N/A
PX190301_Equipment_Manufacturer_TTG PX190301070200 Manufacturer of the equipment used to perform the determination of tissue transglutaminase antibody. 4 N/A
PX190301_Exclusion_Criteria PX190301030000 Exclusion Criteria 4 N/A
PX190301_Hemophilia PX190301010000 Do you have hemophilia? 4 Variable Mapping
PX190301_Sample_Comments PX190301050000 Record any comments about the sample during processing. 4 Variable Mapping
PX190301_TTG_Assay_Results PX190301100000 Results of tissue transglutaminase antibody assay 4 N/A
Research Domain Information
Measure Name:

Celiac Sprue - Assay

Release Date:

December 13, 2010

Definition

This is a two-step serologic measure to determine whether a person is positive for celiac sprue, also known as gluten-sensitive enteropathy.

Purpose

The purpose of this measure is to determine the presence of celiac disease, an intolerance to dietary glutens that has protean manifestations. Surveys in other countries have found celiac sprue in about 0.5 percent to 1.0 percent of the population. Celiac sprue may well be as common in the United States, but it has not been adequately examined.

Keywords

Celiac, celiac sprue, celiac disease, gluten, TTG, EMA, transglutaminase, tissue transglutaminase, endomysial, endomysial antibody, NHANES, National Health and Nutrition Examination Survey, bioassay, gluten-sensitive enteropathy, Gastrointestinal