Summary & Overview
CPT 85400: Plasmin Assay, Laboratory Test
CPT code 85400 denotes a laboratory assay for plasmin, a key fibrinolytic factor involved in clot breakdown. This laboratory diagnostic code is used nationally to document specialized hemostasis testing performed in clinical and hospital laboratories. Accurate coding of plasmin testing supports clinical decision-making in bleeding and thrombotic disorders and informs utilization tracking for laboratory services.
Key payers examined include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the clinical purpose of the test, expected sites of service, and common billing considerations. The publication outlines typical benchmarks for laboratory service lines, coding and reimbursement context at a national level, and relevant clinical indications that drive test utilization. It also highlights policy and coverage themes affecting specialty coagulation testing.
This summary serves clinicians, laboratory managers, and reimbursement professionals seeking a clear, national-level reference for CPT code 85400, its clinical role in fibrinolysis assessment, and the payer landscape relevant to this laboratory procedure.
Billing Code Overview
CPT code 85400 describes a laboratory test performed by a clinical laboratory analyst to measure plasmin, a fibrinolytic factor involved in the breakdown of fibrin clots. This service is a laboratory diagnostic test that evaluates fibrinolytic activity and plasmin presence or concentration in a patient sample.
Typical site of service for CPT code 85400 is a clinical laboratory or hospital laboratory setting where specialized coagulation and fibrinolysis assays are performed. The service involves specimen processing and analytical techniques specific to hemostasis and fibrinolysis testing.
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult referred to an outpatient hospital laboratory by a hematologist or primary care clinician for investigation of abnormal coagulation or fibrinolysis. The patient may present with spontaneous or excessive bleeding, recent thrombolytic therapy monitoring, suspected fibrinolytic disorder, or evaluation after a venous thromboembolism or disseminated intravascular coagulation. A phlebotomy is performed and the specimen is sent to the clinical laboratory. A medical laboratory scientist or clinical laboratory technician performs the plasmin assay (85400) using the appropriate clot-based or chromogenic methodology. Results are reported to the ordering clinician for interpretation and integration with other coagulation studies (e.g., PT/INR, aPTT, fibrinogen, D-dimer). Typical sites of service include hospital outpatient laboratories, independent clinical laboratories, and large hospital inpatient labs when monitoring acute coagulopathy or fibrinolysis.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When billing for the physician/interpretive portion if separate from the facility/lab technical component |
TC |