All specimens submitted to Spectrum Health Laboratory for testing must be appropriately labeled to assure positive identification and optimum integrity of specimens. In accordance with standards issued by The Joint Commission, at least 2 patient identifiers should be used when providing care or treatment of services (National Patient Safety Goal, NSPG.01.01.01). If 2 patient identifiers are not used on the specimen, the specimen will be rejected, the order will be cancelled and a request for recollection will be made. This includes Gyn Cytology (i.e. Pap) specimens.
What are acceptable Patient Identifiers?
Thyroid Peroxidase Antibody (anti-TPO), Blood Level (Test #8524 )
This is the recommended test for the evaluation of Autoimmune Thyroiditis
Thyroglobulin, Tumor Marker, Serum (Test #3069)
It is only indicated for monitoring of thyroid cancer treatment.
This result is reported with an Anti-Tg result to assess for possible interference.
This test should NOT be ordered for associated anti-Tg result provided by reference laboratory.
Thyroglobulin Antibody (anti-Tg) Test
Historically ordered with anti-TPO for evaluation of possible autoimmune thyroiditis.
The literature shows that anti-TPO, alone, has better sensitivity and specificity with only 5% of cases of Autoimmune thyroiditis with anti-TPO negative, anti-Tg positive.
Since 2/2011, requests for anti-Tg have been cancelled per Laboratory Communication: Memo Thyroglobulin Antibody 2/2011
Spectrum Health Regional Laboratory Experience February 2015 – March 2016 (13 months):
357 patients with both Anti-TPO and Anti-Tg results.
*Anti-Tg results were due to concomitantly ordered Thyroglobulin TM requests.
250 patients had positive Anti-TPO and/or Anti-Tg level
193 patients had both positive Anti-TPO and Anti-Tg level
56 patients had positive Anti-TPO and negative Anti-Tg level
1 patient had a negative Anti-TPO and positive Anti-Tg levels
Based on these results, and what is reported in the literature, we are confident of our current practices and strongly request discontinuation of Thyroglobulin TM requests for the associated Anti-Tg result
Caturegli P, De Remigis A, Rose NR. Hashimoto thyroiditis: clinical and diagnostic criteria. Autoimmun Rev. 2014 Apr-May;13(4-5):391-7