---
title: "Cystatin C With eGFR Test: What It Measures"
description: "It estimates kidney filtration using cystatin C to refine eGFR when creatinine is unclear, with easy ordering and Quest lab access via Vitals Vault."
canonical: "https://www.vitalsvault.com/biomarkers/cystatin-c-with-glomerular-filtration-rate-estimated-egfr"
last-updated: 2026-08-22
---

# Cystatin C With eGFR Test: What It Measures

> It estimates kidney filtration using cystatin C to refine eGFR when creatinine is unclear, with easy ordering and Quest lab access via Vitals Vault.

---

Canonical HTML: https://www.vitalsvault.com/biomarkers/cystatin-c-with-glomerular-filtration-rate-estimated-egfr
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