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The CPT® Code 84432 refers to the laboratory test for measuring thyroglobulin (Tg) levels in the blood or fine needle aspirate (FNA) fluid. Thyroglobulin is a protein synthesized by the thyroid gland, serving as a precursor for the synthesis of the two primary thyroid hormones: thyroxine (T4) and triiodothyronine (T3). This test is significant in the evaluation of thyroid function and pathology, particularly in the context of thyroid cancer and autoimmune thyroid diseases. Elevated levels of thyroglobulin in the bloodstream may indicate the presence of certain thyroid conditions, including papillary or follicular thyroid cancer, as well as Hashimoto's thyroiditis, which is also known as Grave's disease. It is important to note that this test is frequently ordered alongside the thyroglobulin antibody test (CPT® Code 86800), as the presence of thyroglobulin antibodies (TgAb) can potentially interfere with the accuracy of the thyroglobulin test results. The collection of a blood sample for this test is performed through a procedure known as venipuncture, which is reportable separately. Additionally, if thyroid cells are needed for analysis, they can be obtained via a fine needle aspiration (FNA), which is also reportable separately. The testing of serum or plasma, as well as FNA fluid, is conducted using a quantitative chemiluminescent immunoassay, a sensitive and specific method for measuring the concentration of thyroglobulin in the samples.
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The thyroglobulin test (CPT® Code 84432) is indicated for the following conditions:
The procedure for obtaining thyroglobulin levels involves several key steps:
After the procedure, patients may experience minimal discomfort at the venipuncture site or from the fine needle aspiration. It is generally recommended that patients remain under observation for a short period to monitor for any immediate adverse reactions. The results of the thyroglobulin test are typically available within a few days, and healthcare providers will discuss the findings with the patient, including any necessary follow-up actions based on the results. It is essential for patients to inform their healthcare provider of any symptoms or concerns that may arise following the procedure.
| Short Descr | ASSAY OF THYROGLOBULIN | Medium Descr | ASSAY OF THYROGLOBULIN | Long Descr | Thyroglobulin | 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 | 233 - Laboratory - Chemistry and Hematology |
| 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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. | GW | Service not related to the hospice patient's terminal condition | 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. | 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. | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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 | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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