Test Category: Immunology
Investigation Name:Tissue transglutaminase antibody (IgA TTG)
Alias or Abbreviation:IgA TTG, Coeliac
Intro:
Indication:Coeliac disease, dermatitis herpetiformis
NOTE:
• Testing should only be carried out when patient is on a gluten-containing diet.
• Total IgA will be tested at the same time as TTG-A testing
• TTG-IgA is the first line test. If the patient’s IgA <0.20g/L then the TTG-IgG is automatically reflexed by lab
• Endomysial IgA antibodies are cascaded onto new positive (first time positive) TTG-A results for confirmation
Further information:
NICE guidelines NG20 (2015) recommend screening with IgA TTG antibodies and IgA as the first line test followed by endomysial IgA antibodies to confirm positive TTG results. IgA antibodies to TTG may be falsely positive especially in liver disease.
Pathology Laboratory:Immunology Laboratory
Requestable Seperately?Yes
Minimum Sample Volume:1mL
Expected Turnaround Time:21 working days
Test Code:TTGA
Sample Type:
Serum Gel Tube (Gold top)Complex Reference Range:<7 U/mL = Negative
Collection Conditions / Other Information:1st class post or Transport
Referred to Another Laboratory?No
Storage Requirements:Ambient temperature
NPEX / PDF Reporting Available:Yes
EQA Scheme:Yes
Further information:First line test Heparin samples are not suitable for analysis.
Lead Contact Details:rwh-tr.bcpsimmunologyclinicalqueries@nhs.net
Email Address For Chasing Results:rwh-tr.ImmunologyLab@nhs.net
Methodology:Fluoroenzymeimmunoassay
UKAS Reference Number:9580 (recommended)
Site Sample Tested:Immunology, New Cross Hospital, Wolverhampton
Minimum Request Interval (MRI):180 days (6 months) over 16y only
Contact Number:01902 695 279 or Ext 85279
