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An infectious agent antigen detection test is a diagnostic procedure that utilizes immunoassay techniques combined with direct optical observation to identify the presence of specific infectious organisms in a specimen sample. This test is categorized under CPT® Code 87899, which is designated for cases where there is no specific code available for the infectious agent being tested. The procedure typically employs a rapid test kit, and the exact methodology may vary depending on the manufacturer and the specific infectious agent in question. Generally, the process begins with the collection of a sample, which may include swabs or aspirates from the patient. The sample is then treated with various reagents that facilitate the extraction of the antigen from the infectious agent. The initial step involves adding a reagent to a tube containing the sample to extract the antigen. Following this, a swab, dipstick, or test strip is introduced into the solution, which may require incubation to allow for proper interaction. A second reagent is often added to the mixture to enhance the reaction. After this step, the swab, dipstick, or strip is removed, and a third reagent may be introduced, or the sample may be transferred to a test cassette or device designed for the assay. The presence of the antigen in the sample is indicated by a color change in the test line or spot, which signifies a positive result, alongside a control line or spot that confirms the test's validity. This procedure is crucial for the rapid identification of infectious agents, aiding in timely diagnosis and treatment decisions.
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The infectious agent antigen detection test is performed for various indications, particularly when there is a need to identify the presence of specific infectious organisms in a patient. The following conditions may warrant the use of this test:
The procedure for conducting an infectious agent antigen detection test involves several key steps, which are outlined as follows:
After the completion of the infectious agent antigen detection test, the results are typically interpreted within a short timeframe, allowing for rapid clinical decision-making. If the test yields a positive result, it may prompt further diagnostic testing or immediate initiation of treatment for the identified infection. In cases of negative results, clinical correlation with patient symptoms and history is essential, and additional testing may be warranted if suspicion of infection remains high. It is also important to document the results and any subsequent actions taken in the patient's medical record to ensure continuity of care and compliance with clinical guidelines.
| Short Descr | AGENT NOS ASSAY W/OPTIC | Medium Descr | IAADIADOO NOT OTHERWISE SPECIFIED | Long Descr | Infectious agent antigen detection by immunoassay with direct optical (ie, visual) observation; not otherwise specified | 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 | 4 | CCS Clinical Classification | 206 - Microscopic examination (bacterial smear, culture, toxicology) |
| 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. | QW | Clia waived test | 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. | 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. | 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. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | 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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| 2022-01-01 | Changed | First appearance of change in codebook. |
| 2021-01-01 | Changed | First appearance of change in CPT® Code Set. |
| 2020-10-06 | Changed | Code description changed. |
| 2009-01-01 | Changed | Code description changed. |
| 1998-01-01 | Added | First appearance in code book in 1998. |
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