Test/Investigation
TTG
Site(s) or Laboratory offering Test/Investigation
NNUH
Units
IU/mL
Also Known as/Frequency of Test
Coeliac Antibodies, IgA tissue Transglutaminase (IgA Ttg) or Endomysial Antibodies; Endomysium Antibodies; IgA Endomysial Antibodies
Indications
IgA tTg is the first line test for coeliac disease; a positive result should be confirmed with a request for EMA. If IgA deficiency is suspected (laboratory findings) total immunoglobulin/electrophoresis and IgG tTG will be requested. All these tests have a good sensitivity and specificity for Coeliac disease if the patient is on a gluten containing diet (2 gluten containing meals daily for 6 weeks)
Sample type
Serum
Turnaround times (TAT) Urgent/Routine/GP or OPD
2 working days
Reference intervals (adult unless stated)
0.0 – 7.0 IU/mL Negative
7.0 – 10.0 IU/mL Equivocal
> 10.0 IU/mL Positive