# eGFR Creatinine-Cystatin C Calculation

> This test calculates how well your kidneys filter waste from your blood by combining measurements of two specific markers, creatinine and cystatin C. Because cystatin C is less affected by muscle mass than creatinine, using both markers provides a more accurate estimate of your kidney function. This helps doctors confirm signs of chronic kidney disease or rule out false alarms caused by factors like diet or body composition. However, this calculation is an estimate and does not identify the specific underlying cause of kidney damage on its own.

- Labcorp code: 121022
- Category: [Heart & Metabolic](https://app.picardo.health/labs/tests/heart-metabolic.md)
- Price: shown at checkout, before payment.
- Blood draw: free at a Labcorp location, or $75.00 at home.
- Order link: https://app.picardo.health/labs/order?tests=121022&ref=assistant

## About ordering

A licensed physician reviews every order before any test is run, and results arrive in the person's Picardo account. Ordering is open to adults 18 and over in the US, except New York, New Jersey, Rhode Island, Pennsylvania, Maryland, Massachusetts, Hawaii and Maine. General health information, not medical advice.