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The CPT® Code 85520 refers to a laboratory test known as the heparin assay. This test is specifically designed to measure the levels of plasma unfractionated heparin (UH) and/or low molecular weight heparin (LMWH) antibodies, commonly referred to as Heparin Anti-Xa. Heparin is a widely used anticoagulant medication that plays a crucial role in both the prevention and treatment of blood clots. The formation of antibodies in response to heparin occurs when it interacts with a protein on the surface of platelets known as platelet factor 4 (PF4). This interaction results in the creation of a heparin-PF4 complex, which the immune system recognizes as foreign. In response, the immune system produces antibodies against this complex. The presence of these antibodies can lead to the activation of platelet production, which in turn triggers the release of more PF4. This cascade of events can result in a serious condition known as immune-mediated heparin-induced thrombocytopenia (HIT type II). HIT type II is characterized by a combination of low platelet counts, the presence of HIT antibodies, and an increased risk of excessive clotting. To perform the heparin assay, a blood sample is collected through a procedure known as venipuncture, which is separately reportable. The test itself involves analyzing platelet-poor plasma using a chromogenic assay, a method that allows for precise measurement of heparin levels and the associated antibodies.
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The heparin assay (CPT® Code 85520) is indicated for the evaluation of patients who may be experiencing complications related to heparin therapy. The following conditions and symptoms warrant the performance of this test:
The procedure for conducting the heparin assay involves several key steps that ensure accurate measurement of heparin levels and antibodies. The following outlines the procedural steps:
After the heparin assay is completed, the patient may be monitored for any immediate reactions, although the procedure is generally safe with minimal risk. The results of the assay will be analyzed and reported to the healthcare provider, who will interpret the findings in the context of the patient's clinical situation. Depending on the results, further management may be required, including adjustments to heparin therapy or additional diagnostic testing to evaluate the patient's coagulation status. It is important for healthcare providers to communicate the results to the patient and discuss any necessary follow-up actions or treatments.
| Short Descr | HEPARIN ASSAY | Medium Descr | HEPARIN ASSAY | Long Descr | Heparin assay | 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. | 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. | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | 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. | 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. | 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 |
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