84100 Assay of phosphorus
Also known as: phosphorus test, phosphate assay, serum phosphate
Quantitative assay of serum or plasma phosphorus (phosphate) concentration, an electrolyte essential for bone metabolism and energy production.
In Plain Language
blood phosphate level test
Clinical Context
Ordered to evaluate bone health, mineral metabolism, kidney function, and parathyroid disorders; abnormal levels associated with rickets, hyperparathyroidism, and renal disease.
RVU Information
CPT 84100 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 84100?
CPT 84100 (Assay of phosphorus) is a Pathology & Lab code. Quantitative assay of serum or plasma phosphorus (phosphate) concentration, an electrolyte essential for bone metabolism and energy production.
Who uses CPT code 84100?
CPT 84100 is used by Clinical Chemistry, Pathology, Internal Medicine. Ordered to evaluate bone health, mineral metabolism, kidney function, and parathyroid disorders; abnormal levels associated with rickets, hyperparathyroidism, and renal disease.
When is CPT 84100 used?
Ordered to evaluate bone health, mineral metabolism, kidney function, and parathyroid disorders; abnormal levels associated with rickets, hyperparathyroidism, and renal 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.