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The CPT® Code 85306 refers to a laboratory test that measures the levels of free protein S, which is a vitamin K dependent glycoprotein found in the blood. This protein exists in both free and bound forms within the plasma and plays a crucial role as a non-enzyme cofactor in the activation of activated protein C (APC), a key component in the regulation of blood coagulation. A deficiency in protein S can lead to an increased risk of abnormal blood clotting, which may result in recurrent venous thrombosis or embolism. Such deficiencies are often linked to rare inherited genetic disorders, but they can also be acquired due to various conditions such as liver disease, vitamin K deficiency, disseminated intravascular coagulation (DIC), pregnancy, and certain inflammatory syndromes. In women, a deficiency in protein S is particularly concerning as it is associated with a heightened risk of fetal loss during pregnancy. The test for free protein S is primarily utilized to screen individuals for potential deficiencies. If a positive result is obtained, it is recommended to perform a follow-up test for total protein S to further classify the type of deficiency present. There are different types of protein S deficiency: Type I is characterized by low levels of both free and total protein S; Type III shows a decrease in only free protein S; and Type II presents with normal antigenic levels but decreased cofactor activity. Prior to testing, patients are advised to avoid anticoagulants such as warfarin or coumadin for a period of two weeks to ensure accurate results. The blood sample required for this test is collected through a venipuncture, and the analysis is conducted on platelet-poor plasma using a microlatex particle-mediated immunoassay method.
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The test for free protein S is indicated for the following conditions:
The procedure for testing free protein S involves several key steps:
After the procedure, patients may resume their normal activities immediately, as there are typically no significant post-procedure restrictions. However, it is important for patients to follow up with their healthcare provider to discuss the test results and any necessary further evaluations or treatments based on the findings. If a deficiency is confirmed, appropriate management strategies will be discussed to mitigate the risks associated with protein S deficiency, particularly in relation to thrombotic events.
| Short Descr | CLOT INHIBIT PROT S FREE | Medium Descr | CLOTTING INHIBITORS PROTEIN S FREE | Long Descr | Clotting inhibitors or anticoagulants; protein S, free | 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 | 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. | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | 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. | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | GA | Waiver of liability statement issued as required by payer policy, individual case | GZ | Item or service expected to be denied as not reasonable and necessary | 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 | Short Descriptor changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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