Summary & Overview

CPT 85250: Factor IX (PTC/Christmas) Clotting Test

CPT code 85250 represents a laboratory clotting assay to detect the presence of factor IX (PTC or Christmas factor) in a patient's serum. This assay is clinically important for diagnosing or monitoring bleeding disorders such as hemophilia B and for evaluating unexplained coagulopathies. Nationally, accurate coding for specialized coagulation tests supports appropriate clinical interpretation, care coordination, and claim adjudication.

Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical purpose of the test, typical sites of service, and the role of the code in laboratory billing. The publication also addresses payer coverage patterns and common billing modifiers where available, as well as practical benchmarking and policy context tied to laboratory service lines.

This summary provides clinical context for billing staff, laboratory managers, and policy analysts who need to understand how CPT code 85250 is used in practice, which services it represents, and what to expect when processing or reviewing claims for factor IX testing. Data not available in the input is noted where applicable.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare85250CPTLaboratoryCoagulationFactor IXHemophilia BClinical LaboratoryLab BillingDiagnostic Test

Billing Code Overview

CPT code 85250 describes a laboratory clotting test performed by a lab analyst to determine the presence of factor IX (PTC or Christmas factor) in the patient’s serum. This is a specialized coagulation assay used to identify or quantify factor IX, commonly relevant to the evaluation of bleeding disorders such as hemophilia B or acquired factor IX deficiencies.

Service type: Laboratory coagulation assay
Typical site of service: Clinical laboratory or hospital laboratory

Clinical & Coding Specifications

Clinical Context

A typical patient is a male with a personal or family history of bleeding or prolonged bleeding after surgery or trauma, or a male child evaluated for hemophilia during a hematology workup. The clinician orders a specific factor IX (Christmas factor, PTC) assay when initial screening tests such as prothrombin time (PT) and activated partial thromboplastin time (aPTT) suggest an intrinsic pathway defect or when a patient has a known hemophilia B diagnosis and requires factor activity monitoring. The clinical workflow begins with a blood draw in an outpatient laboratory or hospital phlebotomy service. The specimen is processed in the clinical laboratory: plasma is separated, and a clotting assay specific to factor IX activity is performed by a laboratory technologist or hematopathology specialist. Results are reviewed by a laboratory director or hematologist, reported in the electronic medical record, and used to guide treatment decisions such as factor replacement therapy, perioperative management, or genetic counseling. Typical sites of service include hospital laboratories, independent clinical laboratories, and large ambulatory clinic laboratory services.

Coding Specifications

Modifier	Description	When to Use
`26`	Professional component	Use when reporting only the professional component of a laboratory service if applicable (rare for waived or fully technical lab tests).
`TC`	Technical component	Use when billing only the technical component of the test (laboratory supplies, instrument, technician time).
`90`	Reference (outside) laboratory	Use when the specimen is sent to an outside/independent laboratory for testing.
`91`	Repeat clinical diagnostic laboratory test	Use when the same test is repeated on a subsequent specimen to confirm an unexpected result.
`52`	Reduced services	Use when the test was partially performed or limited in scope.
`53`	Discontinued procedure	Use when the test collection or processing was started but discontinued for patient safety or other valid reasons.
`59`	Distinct procedural service	Not in the provided list; omitted.
`95`	Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system	Use when results review or consultation occurs via synchronous telemedicine (if applicable to interpretation).
`91`	Repeat — duplicate entry already listed above; duplicates avoided.
`26`	Professional component — duplicate entry above; duplicates avoided.

Taxonomy Code	Specialty	Notes
207RH0000X	Hematology	Hematologists oversee coagulation testing and interpretation.
2080P0207X	Pathology	Clinical pathologists/hematopathologists supervise laboratory testing and result validation.
363L00000X	Clinical Laboratory	Medical technologists and laboratory directors manage test performance and reporting.
208000000X	Internal Medicine	Internists order and act on factor IX results for chronic disease management.
207L00000X	Pediatrics	Pediatric hematologists evaluate children for congenital factor IX deficiency.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
Data not available in the input.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`85307`	Thromboplastin time (e.g., partial thromboplastin time)	Common initial screening test for intrinsic pathway abnormalities before factor-specific assays.
`85025`	Blood count; complete (CBC) automated and automated differential	Baseline evaluation when bleeding or preoperative assessment prompts coagulation testing.
`85576`	Fibrinogen; quantitative	Performed alongside factor assays to assess other causes of bleeding.
`93975`	Duplex scan, extremity veins (non-arterial)	Not directly related; omitted if not applicable.