Summary & Overview
CPT 84585: Urine Vanillylmandelic Acid (VMA) Quantification
CPT code 84585 designates a laboratory assay that quantifies vanillylmandelic acid (VMA) in urine. VMA testing is used in the biochemical evaluation of catecholamine metabolism and can support the diagnosis and monitoring of conditions such as catecholamine-secreting tumors. Nationally, this test is part of diagnostic workflows in endocrinology, oncology, and nephrology labs and is relevant to clinical laboratories, inpatient hospital labs, and outpatient reference labs.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication provides readers with clinical context for the assay, typical sites of service, payer coverage considerations, and operational benchmarks where available. It outlines common billing modifiers and situational coding notes provided in the input, and indicates when specific data elements were not supplied.
Readers will learn the clinical purpose of CPT code 84585, how the service is typically delivered, and the payer landscape relevant to this lab assay. The summary also flags areas where detailed payer policy or reimbursement benchmarks are not available in the input. This resource is intended to support billing, coding, and administrative staff, as well as clinicians seeking a concise reference to the test’s clinical role and billing identifier.
Billing Code Overview
CPT code 84585 describes a laboratory test that measures vanillylmandelic acid (VMA) in patient urine. The procedure involves a lab analyst performing quantitative analysis of urinary VMA to assist in the biochemical evaluation of catecholamine metabolism.
Service type: Clinical laboratory diagnostic test
Typical site of service: Clinical laboratory or hospital laboratory
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult presenting to outpatient endocrine clinic or primary care with symptoms suggestive of catecholamine-secreting tumors (pheochromocytoma or paraganglioma), such as episodic headaches, severe hypertension, palpitations, diaphoresis, or orthostatic hypotension. The clinician orders a 24-hour urine collection for measurement of vanillylmandelic acid (VMA) to assess catecholamine metabolism when plasma free metanephrines are unavailable or as a complementary test. The patient receives written collection instructions and a preservative when indicated, collects all urine for 24 hours, refrigerates the specimen during collection, and returns it to the clinic or laboratory. The laboratory analyst performs CPT 84585 to quantify urinary VMA using an appropriate validated method (e.g., HPLC with electrochemical detection or mass spectrometry). Results are reported to the ordering clinician, who interprets the value in the context of medications, dietary restrictions, renal function, and clinical presentation. Typical sites of service include hospital outpatient laboratory, independent clinical laboratory, and ambulatory clinic with on-site phlebotomy and specimen handling capabilities.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional interpretation component by a qualified laboratory physician/analyst (rare for most chemistry tests). |