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The CPT® Code 84436 refers to the laboratory test for total thyroxine, commonly known as T4. This test involves obtaining a blood sample to measure the levels of total thyroxine in the bloodstream. Thyroxine is a crucial hormone produced by the thyroid gland, and it plays a significant role in regulating various metabolic processes in the body. The total thyroxine measurement includes both bound and unbound (free) thyroxine, providing a comprehensive overview of thyroid function. This test is essential for diagnosing thyroid disorders, specifically hyperthyroidism, where the thyroid is overactive, and hypothyroidism, where the thyroid is underactive. The evaluation of total thyroxine levels helps healthcare providers assess the overall functioning of the thyroid gland and determine appropriate treatment options. The methodology employed for this test is electrochemiluminescent immunoassay, which is a sensitive and accurate technique for measuring hormone levels in the blood.
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The total thyroxine test (CPT® Code 84436) is indicated for the following conditions:
The procedure for obtaining a total thyroxine level (CPT® Code 84436) involves several key steps:
After the total thyroxine test is performed, there are generally no specific post-procedure care requirements for the patient. However, patients may be advised to wait for the results, which are typically available within a few days. It is important for patients to follow up with their healthcare provider to discuss the results and any necessary further actions or treatments based on the findings. Additionally, if the test indicates abnormal levels of thyroxine, further testing or evaluation may be recommended to assess thyroid function more comprehensively.
| Short Descr | ASSAY OF TOTAL THYROXINE | Medium Descr | ASSAY OF THYROXINE TOTAL | Long Descr | Thyroxine; total | 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 | 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. | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 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. | LT | Left side (used to identify procedures performed on the left side of the body) | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GX | Notice of liability issued, voluntary under payer policy | Q4 | Service for ordering/referring physician qualifies as a service exemption | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | QW | Clia waived test | RT | Right side (used to identify procedures performed on the right side of the body) | SA | Nurse practitioner rendering service in collaboration with a physician | 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 | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| Pre-1990 | Added | Code added. |
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