What does the Estimated Glomerular Filtration Rate (eGFR) primarily measure?

The Estimated Glomerular Filtration Rate (eGFR) primarily measures how well the kidneys are filtering waste from the blood, particularly focusing on the filtration of creatinine, a waste product of muscle metabolism. The eGFR calculation is based on serum creatinine levels, along with factors such as age, gender, and race, providing an estimate of kidney function.

Correct interpretation of eGFR is crucial for assessing kidney health and detecting kidney disease at an early stage. Monitoring eGFR allows healthcare providers to evaluate how well the kidneys are functioning and guide treatment decisions.

Other options, while related to kidney function, do not directly pertain to what eGFR measures. For instance, urine creatinine levels can provide information about kidney function, but eGFR specifically estimates the rate at which the kidneys filter blood, making serum levels more relevant. Blood pressure in the kidneys and electrolyte balance are important concepts in renal physiology, but they are not directly reflected in the eGFR measurement. Similarly, protein levels in plasma can indicate various health conditions but are not the focus of what eGFR evaluates.