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85301 Antithrombin iii antigen

Pathology & Lab

Also known as: antithrombin antigen, AT III antigen

Measurement of antithrombin III (antithrombin) antigen concentration using immunoassay to quantify antithrombin protein levels independent of functional activity.

In Plain Language

anticlotting protein level; antithrombin measurement

Clinical Context

Evaluates discordance between antithrombin activity and antigen; may reveal dysfunctional antithrombin variants or heparin-associated antithrombin consumption.

RVU Information

CPT 85301 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.

Billing & Documentation

Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.

How This Code Compares

This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.

Specialties

Clinical PathologyCoagulationHematology

Frequently Asked Questions

What is CPT code 85301?

CPT 85301 (Antithrombin iii antigen) is a Pathology & Lab code. Measurement of antithrombin III (antithrombin) antigen concentration using immunoassay to quantify antithrombin protein levels independent of functional activity.

Who uses CPT code 85301?

CPT 85301 is used by Clinical Pathology, Coagulation, Hematology. Evaluates discordance between antithrombin activity and antigen; may reveal dysfunctional antithrombin variants or heparin-associated antithrombin consumption.

When is CPT 85301 used?

Evaluates discordance between antithrombin activity and antigen; may reveal dysfunctional antithrombin variants or heparin-associated antithrombin consumption.

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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.