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Official Description

Thyroglobulin antibody

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 86800 refers to the laboratory test for measuring thyroglobulin antibodies. Thyroglobulin (Tg) is a specific protein produced by the thyroid gland, playing a crucial role in the synthesis, storage, and release of thyroid hormones. Under normal circumstances, Tg is not present in the bloodstream; however, it can enter systemic circulation when thyroid follicles are compromised due to various factors such as inflammation, hemorrhage, or abnormal growth patterns. When Tg is released into the bloodstream, the immune system may recognize it as a foreign substance, leading to the formation of auto-antibodies that specifically target this protein. The thyroglobulin antibody test is utilized either independently or in conjunction with other diagnostic tests to identify autoimmune thyroid diseases. Additionally, it serves to assess the reliability of Tg results in patients diagnosed with follicular-cell derived thyroid carcinoma, where accurate measurement is critical for effective management. The test is performed by obtaining a blood sample through venipuncture, which is reported separately, and the serum is analyzed using a quantitative chemiluminescent immunoassay method, ensuring precise measurement of the thyroglobulin antibodies present in the sample.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The thyroglobulin antibody test (CPT® Code 86800) is indicated for the following conditions:

  • Autoimmune Thyroid Disease This test is performed to diagnose autoimmune thyroid conditions, where the immune system mistakenly attacks the thyroid gland.
  • Evaluation of Thyroid Carcinoma The test may be used to evaluate potentially unreliable thyroglobulin results in patients with follicular-cell derived thyroid carcinoma, aiding in the assessment of disease status.

2. Procedure

The procedure for conducting the thyroglobulin antibody test involves several key steps:

  • Step 1: Patient Preparation Prior to the test, the patient may be instructed to avoid certain medications or supplements that could interfere with the results. It is essential to ensure that the patient is adequately informed about the procedure and any necessary preparations.
  • Step 2: Venipuncture A qualified healthcare professional performs venipuncture to obtain a blood sample from the patient. This step is crucial as the sample will be used for the subsequent analysis of thyroglobulin antibodies. The site of venipuncture is typically cleaned with an antiseptic to minimize the risk of infection.
  • Step 3: Serum Separation After collecting the blood sample, it is processed to separate the serum from the cellular components. This is typically done by centrifugation, which allows for the clear serum to be isolated for testing.
  • Step 4: Testing The serum is then subjected to a quantitative chemiluminescent immunoassay. This method utilizes specific antibodies that bind to thyroglobulin antibodies present in the serum, allowing for accurate measurement of their concentration.
  • Step 5: Result Interpretation Once the testing is complete, the results are analyzed and interpreted by a qualified laboratory professional. The findings are then reported to the physician, who will use the information to guide further clinical decisions.

3. Post-Procedure

After the thyroglobulin antibody test is completed, patients may experience minimal discomfort at the venipuncture site, which typically resolves quickly. There are no specific post-procedure care instructions required for this test; however, patients should be advised to monitor the site for any signs of excessive bleeding or infection. The results of the test will be communicated to the patient by their healthcare provider, who will discuss the implications of the findings and any necessary follow-up actions or additional testing that may be required based on the results.

Short Descr THYROGLOBULIN ANTIBODY
Medium Descr THYROGLOBULIN ANTIBODY
Long Descr Thyroglobulin antibody
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 235 - Other Laboratory
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
Q4 Service for ordering/referring physician qualifies as a service exemption
GA Waiver of liability statement issued as required by payer policy, individual case
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
GY Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GZ Item or service expected to be denied as not reasonable and necessary
26 Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
95 Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system.
GW Service not related to the hospice patient's terminal condition
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
Q6 Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area
QW Clia waived test
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
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Pre-1990 Added Code added.
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