84540 Assay of urine/urea-n
Also known as: urine urea nitrogen, 24-hour UUN, urinary urea
Quantitative assay of urine urea nitrogen concentration reflecting nitrogen excretion and protein metabolism.
In Plain Language
urine nitrogen test
Clinical Context
Evaluates nitrogen balance and protein metabolism; used to assess nutritional status and renal function.
RVU Information
CPT 84540 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
Frequently Asked Questions
What is CPT code 84540?
CPT 84540 (Assay of urine/urea-n) is a Pathology & Lab code. Quantitative assay of urine urea nitrogen concentration reflecting nitrogen excretion and protein metabolism.
Who uses CPT code 84540?
CPT 84540 is used by Clinical Chemistry, Nephrology, Nutrition. Evaluates nitrogen balance and protein metabolism; used to assess nutritional status and renal function.
When is CPT 84540 used?
Evaluates nitrogen balance and protein metabolism; used to assess nutritional status and renal function.
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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.