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83521 Ig light chains free each

Pathology & Lab

Also known as: free light chains assay, FLC test, kappa/lambda ratio

Quantitative measurement of free immunoglobulin light chains (kappa and lambda) in serum or urine using immunoassay methods.

In Plain Language

protein in urine or blood test; multiple myeloma marker

Clinical Context

Evaluation of monoclonal gammopathy, multiple myeloma, and light chain disease. FLC ratio is sensitive marker for plasma cell dyscrasias and monoclonal kidney disease.

RVU Information

CPT 83521 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

PathologyHematologyOncology

Frequently Asked Questions

What is CPT code 83521?

CPT 83521 (Ig light chains free each) is a Pathology & Lab code. Quantitative measurement of free immunoglobulin light chains (kappa and lambda) in serum or urine using immunoassay methods.

Who uses CPT code 83521?

CPT 83521 is used by Pathology, Hematology, Oncology. Evaluation of monoclonal gammopathy, multiple myeloma, and light chain disease. FLC ratio is sensitive marker for plasma cell dyscrasias and monoclonal kidney disease.

When is CPT 83521 used?

Evaluation of monoclonal gammopathy, multiple myeloma, and light chain disease. FLC ratio is sensitive marker for plasma cell dyscrasias and monoclonal kidney disease.

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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.