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The CPT® Code 84445 refers to the measurement of thyroid stimulating immune globulins (TSI) in a blood sample. This test is crucial for evaluating the presence and levels of TSI, which are autoantibodies produced by the immune system. These autoantibodies specifically bind to the surface of follicular cells in the thyroid gland, mimicking the action of thyroid stimulating hormone (TSH). As a result, they can lead to an overproduction and secretion of thyroid hormones, which is a hallmark of hyperthyroidism. The test is particularly significant in diagnosing conditions such as Grave's disease, Hashimoto's thyroiditis, and toxic multinodular goiter, all of which are associated with overactive thyroid function. The methodology employed for this test includes bioassay and chemiluminescence, both of which are advanced techniques used to accurately measure the levels of TSI in the blood, providing essential information for the diagnosis and management of thyroid-related disorders.
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The test associated with CPT® Code 84445 is indicated for the evaluation of thyroid stimulating immune globulins (TSI) in patients suspected of having hyperthyroidism. The specific conditions and symptoms for which this test is performed include:
The procedure for obtaining a blood sample to measure thyroid stimulating immune globulins (TSI) involves several key steps:
After the blood sample has been collected, there are generally no specific post-procedure care requirements for the patient. However, patients may be advised to apply pressure to the puncture site to minimize any bleeding and to keep the area clean and dry. Results from the TSI test will typically be available within a few days, and the healthcare provider will discuss the findings with the patient, including any necessary follow-up actions or treatments based on the results.
| Short Descr | ASSAY OF TSI GLOBULIN | Medium Descr | THYROID STIMULATING IMMUNE GLOBULINS TSI | Long Descr | Thyroid stimulating immune globulins (TSI) | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | 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. | 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. | 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 | GA | Waiver of liability statement issued as required by payer policy, individual case | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GW | Service not related to the hospice patient's terminal condition | 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 | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days |
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| 2013-01-01 | Changed | Short Descriptor changed. |
| 2002-01-01 | Changed | Code description changed. |
| Pre-1990 | Added | Code added. |
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