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The CPT® Code 87329 refers to a laboratory test specifically designed for the detection of giardia antigen in fecal samples using various immunoassay techniques. Giardia is a protozoan parasite that can contaminate food and water, leading to gastrointestinal issues such as diarrhea, abdominal pain, and weight loss when ingested. The test employs several methodologies, including enzyme immunoassay (EIA), enzyme-linked immunosorbent assay (ELISA), fluorescence immunoassay (FIA), and immunochemiluminometric assay (IMCA), to identify the presence of giardia antigens. These techniques are capable of detecting even minute quantities of the antigen by utilizing specific antibodies that bind to the giardia antigen in the sample. In the laboratory, a fecal sample is collected, which may be preserved in formalin or sent fresh for analysis. The EIA and ELISA methods involve adding a secondary enzyme-labeled antibody that binds to the antigen-antibody complex, resulting in a chromogenic reaction that produces a visible color change or fluorescence, allowing for qualitative or semi-quantitative assessment based on colorimetric readings. The FIA method utilizes a fluorescent compound to detect the binding of the detection antibody to the giardia antigen, emitting light at a different wavelength, which is measured to determine the presence of the antigen. Lastly, the IMCA technique employs antibodies labeled with a chemiluminescent substance, enabling the identification and quantification of the antigen-antibody complex through light emission. This comprehensive approach ensures accurate detection of giardia, aiding in the diagnosis and management of infections caused by this parasite.
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The procedure associated with CPT® Code 87329 is indicated for the detection of giardia antigen in patients who present with gastrointestinal symptoms. The following conditions may warrant the performance of this test:
The procedure for detecting giardia antigen using CPT® Code 87329 involves several key steps, which are outlined below:
After the procedure, the laboratory will provide the results to the requesting physician, who will interpret the findings in the context of the patient's clinical presentation. If giardia antigen is detected, appropriate treatment options will be discussed with the patient. It is important for the physician to consider follow-up testing or additional diagnostic procedures if symptoms persist or if there are concerns about the accuracy of the test results. Patients may also be advised on preventive measures to avoid future infections, such as proper hygiene and safe food and water practices.
| Short Descr | GIARDIA AG IA | Medium Descr | IAAD IA GIARDIA | 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; giardia | 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 | 2 | 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. | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | GW | Service not related to the hospice patient's terminal condition | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | 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. | 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. | 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 | 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 | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | 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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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 changed. |
| 2016-01-01 | Changed | Description Changed |
| 2011-01-01 | Changed | Short description changed. |
| 2007-01-01 | Changed | Code description changed. |
| 2004-01-01 | Added | First appearance in code book in 2004. |
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