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The CPT® Code 87449 refers to a laboratory test designed to detect infectious agent antigens in blood and other body fluids through various immunoassay techniques. This code encompasses a range of methodologies, including enzyme immunoassay (EIA), enzyme-linked immunosorbent assay (ELISA), fluorescence immunoassay (FIA), and immunochemiluminometric assay (IMCA). Each of these techniques employs specific biochemical processes to identify and quantify antigens, which are substances that provoke an immune response. The EIA and ELISA methods utilize labeled antibodies that bind to the target antigens, producing a chromogenic reaction that results in a visible color change, thereby allowing for qualitative or semiquantitative measurement of the antigen's presence. The FIA method employs fluorescent compounds to detect the binding of antibodies to the antigens, while the IMCA method uses chemiluminescent substances to measure the light emitted from the antigen-antibody complex. This code is specifically used for reporting tests that do not have a dedicated code for the detection of infectious agent antigens using these immunoassay techniques, ensuring accurate billing and documentation for each organism tested. For tests involving multiple organisms, the CPT® Code 87451 should be used, which pertains to polyvalent testing that identifies serological subtypes of organisms.
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The CPT® Code 87449 is indicated for use in laboratory testing to identify infectious agent antigens in patients who may be exhibiting symptoms of infection or who are at risk for infectious diseases. This testing is crucial for diagnosing various infectious conditions and can be utilized in a range of clinical scenarios, including:
The procedure for conducting the test associated with CPT® Code 87449 involves several key steps, which are outlined as follows:
After the completion of the immunoassay testing associated with CPT® Code 87449, the laboratory will provide a report detailing the findings. Healthcare providers will review these results to make informed decisions regarding patient care. Depending on the results, further diagnostic testing or treatment may be necessary. It is important for healthcare professionals to communicate the results to the patient and discuss any required follow-up actions. Additionally, proper documentation of the test results and any subsequent clinical decisions is essential for maintaining accurate medical records and ensuring compliance with billing and coding standards.
| Short Descr | NOS EACH ORGANISM AG IA | Medium Descr | IAAD IA NOT OTHERWISE SPECIFIED EACH ORGANISM | Long Descr | Infectious agent antigen detection by immunoassay technique (eg, enzyme immunoassay [EIA], enzyme-linked immunosorbent assay [ELISA], fluorescence immunoassay [FIA], immunochemiluminometric assay [IMCA]), qualitative or semiquantitative; not otherwise specified, each organism | 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) | Yes | 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 | 3 | CCS Clinical Classification | 206 - Microscopic examination (bacterial smear, culture, toxicology) |
| 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. | 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. | 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. | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | QW | Clia waived test | GW | Service not related to the hospice patient's terminal condition | 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. | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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). | GA | Waiver of liability statement issued as required by payer policy, individual case | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | 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) | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter |
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Notes
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| 2022-01-01 | Changed | First appearance of change in codebook. |
| 2022-01-01 | Note | Grammatical correction. |
| 2021-01-01 | Changed | First appearance of change in CPT® Code Set. |
| 2020-10-06 | Changed | Code description changed. |
| 2016-01-01 | Changed | Description Changed |
| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Changed | Code description changed. |
| 1998-01-01 | Added | First appearance in code book in 1998. |
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