Summary & Overview
CPT 0259U: GFR by NMR Serum Assay, Labtech Diagnostics
CPT code 0259U denotes a proprietary laboratory test (PLA) that estimates glomerular filtration rate (GFR) using nuclear magnetic resonance (NMR) spectroscopy combined with an immunoassay. The test, produced by Labtech™ Diagnostics and performed on a serum specimen, measures myo‑inositol, valine, creatinine, and cystatin C, then uses an algorithm plus demographic inputs to generate an estimated GFR. Nationally, this code matters as algorithmic, manufacturer‑specific assays for kidney function raise distinct coverage, coding, and clinical interpretation considerations compared with traditional creatinine‑based GFR estimation.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise review of the code’s clinical context, typical sites of service, and how the test is constructed. The publication summarizes payer coverage patterns and benchmarks where available, outlines common billing modifiers and operational considerations, and highlights relevant policy and coding updates that affect proprietary laboratory analyses. The briefing provides the clinical and billing essentials needed by laboratory billing teams, clinicians ordering kidney function testing, and policy analysts tracking novel diagnostic assays in nephrology.
Billing Code Overview
CPT code 0259U is a Proprietary Laboratory Analyses (PLA) code for a single, manufacturer‑specific laboratory test: a serum-based GFR by NMR performed by Labtech™ Diagnostics. The assay combines nuclear magnetic resonance (NMR) spectroscopy measurements of myo‑inositol, valine, and creatinine with an immunoassay measurement of cystatin C. An algorithmic analysis of these laboratory results alongside patient demographic data produces an estimated glomerular filtration rate (GFR) to assess kidney function, primarily for patients with chronic kidney disease.
Service Type: Laboratory — Proprietary molecular/biochemical assay with algorithmic interpretation
Typical Site of Service: Clinical laboratory (specimen collected and processed as a serum test)
Clinical & Coding Specifications
Clinical Context
A 62-year-old patient with long-standing type 2 diabetes and hypertension is referred by their nephrologist for monitoring of chronic kidney disease (CKD). The clinician orders a laboratory-based estimated glomerular filtration rate (eGFR) using the proprietary Labtech™ Diagnostics assay reported with CPT 0259U. Serum is collected during an outpatient phlebotomy visit. The laboratory performs nuclear magnetic resonance (NMR) spectroscopy to quantify myo‑inositol, valine, and creatinine, and an immunoassay for cystatin C. The lab combines these analytes with patient demographic data (age, sex, race as available) through the manufacturer's algorithm to produce an eGFR report. Results are transmitted to the ordering nephrologist and primary care provider for staging of CKD, medication dosing adjustments, and longitudinal monitoring. Typical site of service is an outpatient laboratory or hospital outpatient phlebotomy center; the service type is a laboratory diagnostic assay (Proprietary Laboratory Analyses).
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
00 | Default/No modifier | Use when no specific modifier applies to the service |
26 |