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The CPT® Code 84479 refers to the measurement of thyroid hormone uptake, specifically for T3 (triiodothyronine) or T4 (thyroxine), which is also known as the thyroid hormone binding ratio (THBR). This procedure involves obtaining a blood sample from the patient to assess how well these thyroid hormones are being taken up by the body's tissues. The uptake of thyroid hormones is influenced by three key proteins: thyroid binding globulin (TBG), transthyretin, and albumin. These proteins bind to thyroid hormones, rendering them inactive in the bloodstream. The thyroid hormone uptake is expressed as a ratio, comparing the uptake in a solid matrix to the uptake in serum. This calculation of the THBR is crucial for physicians as it aids in identifying potential abnormalities in binding proteins that may affect thyroid hormone function. The test is conducted using an electrochemiluminescent immunoassay, a sensitive and specific method for measuring hormone levels in the blood.
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The procedure associated with CPT® Code 84479 is indicated for the evaluation of thyroid function and potential abnormalities in thyroid hormone binding. The following conditions may warrant this test:
The procedure for CPT® Code 84479 involves several key steps to ensure accurate measurement of thyroid hormone uptake. First, a blood sample is collected from the patient, typically via venipuncture. This sample is then processed to separate the serum, which contains the thyroid hormones and binding proteins. Following this, the electrochemiluminescent immunoassay is performed. This advanced testing method utilizes specific antibodies that bind to the thyroid hormones in the serum. The assay measures the amount of T3 or T4 that is taken up by the solid matrix compared to the serum uptake. The results are calculated to provide the thyroid hormone binding ratio (THBR), which is essential for interpreting the patient's thyroid function and identifying any binding protein abnormalities.
After the procedure associated with CPT® Code 84479, patients may experience minimal discomfort at the venipuncture site, which typically resolves quickly. There are no specific post-procedure care requirements, and patients can generally resume normal activities immediately. The results of the test will be analyzed by the physician, who will discuss the findings with the patient and determine any necessary follow-up actions based on the THBR results and overall clinical context.
| Short Descr | ASSAY OF THYROID (T3 OR T4) | Medium Descr | THYROID HORM UPTK/THYROID HORMONE BINDING RATIO | Long Descr | Thyroid hormone (T3 or T4) uptake or thyroid hormone binding ratio (THBR) | 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 |
| 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. | 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 | GW | Service not related to the hospice patient's terminal condition | 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 | 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 | 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. | 51 | Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d). | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | GX | Notice of liability issued, voluntary under payer policy | KX | Requirements specified in the medical policy have been met | QW | Clia waived test | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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| Pre-1990 | Added | Code added. |
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