Summary & Overview
CPT 85337: Thrombomodulin Level Measurement in Plasma
CPT code 85337 denotes a laboratory assay to determine thrombomodulin levels in patient plasma, a specialized test relevant to coagulation and endothelial function. Nationally, access to and use of this assay matter for clinicians managing complex coagulation disorders, research settings, and hospitals monitoring endothelial injury. The code is used for billing when a lab performs the analytic measurement of thrombomodulin concentration.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise national overview of clinical context for the assay, common payer coverage patterns, and practical billing considerations tied to CPT code 85337. The publication outlines benchmark elements such as typical sites of service (clinical and hospital laboratories), common service descriptors, and the role of the test in specialty coagulation evaluation. It also highlights areas where policy updates and payer-specific coverage criteria can affect utilization and claims processing.
This summary serves clinical laboratory managers, billing professionals, and policy analysts seeking a focused briefing on CPT code 85337 and its clinical and billing implications at a national level.
Billing Code Overview
CPT code 85337 describes a laboratory procedure in which a lab analyst measures the level of thrombomodulin in patient plasma. This test is a specialized coagulation-related laboratory assay used to assess endothelial function and coagulation pathway modulation.
Service Type: Laboratory diagnostic test
Typical Site of Service: Clinical laboratory or hospital laboratory
Clinical & Coding Specifications
Clinical Context
A 58-year-old hospitalized patient with unexplained coagulopathy and suspected endothelial dysfunction undergoes evaluation of thrombotic risk. The treating hematologist orders a thrombomodulin plasma level to assess endothelial cell activation or injury as part of a broader coagulation workup. A phlebotomist collects a citrated plasma specimen; the specimen is processed in the hospital clinical laboratory by a laboratory technologist using an immunoassay to quantify thrombomodulin concentration. Results are reviewed by the ordering physician and integrated with other coagulation tests (e.g., D-dimer, protein C activity, antithrombin levels) to inform diagnosis of conditions such as thrombotic microangiopathy, disseminated intravascular coagulation, or suspected endothelial injury from sepsis or chemotherapy. Typical documentation includes the order, specimen type and collection time, assay method, result with reference range, and interpretation by the ordering clinician.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | No modifier specified / default | Use when no specific modifier applies to the billed service |
26 | Professional component | Use when billing physician or laboratory professional bills only the interpretive/professional portion of the test |