Which laboratory value is commonly used to assess kidney function?

Which laboratory value is commonly used to assess kidney function?

• A. Serum potassium
• B. Serum creatinine or estimated glomerular filtration rate (eGFR)
• C. Serum bilirubin
• D. Hemoglobin A1c

Answer: (B)

Kidney function is measured by how efficiently the kidneys filter waste from the blood, and the most commonly used measure is serum creatinine together with the estimated glomerular filtration rate (eGFR). Serum creatinine is a waste product from muscle metabolism that is normally cleared by filtration in the kidneys; when filtration declines, creatinine rises. The eGFR uses creatinine along with factors like age and sex to estimate how much blood the kidneys filter per minute, providing a clearer picture of kidney function and helping stage any chronic kidney disease. Other labs point to different organs or processes. Potassium levels can be affected by kidney function but don’t directly quantify filtration capacity. Bilirubin reflects liver and biliary tract health. HbA1c shows long-term glucose control rather than kidney function. So the combination of creatinine and eGFR is the best choice for assessing how well the kidneys are functioning.

Kidney function is measured by how efficiently the kidneys filter waste from the blood, and the most commonly used measure is serum creatinine together with the estimated glomerular filtration rate (eGFR). Serum creatinine is a waste product from muscle metabolism that is normally cleared by filtration in the kidneys; when filtration declines, creatinine rises. The eGFR uses creatinine along with factors like age and sex to estimate how much blood the kidneys filter per minute, providing a clearer picture of kidney function and helping stage any chronic kidney disease.

Other labs point to different organs or processes. Potassium levels can be affected by kidney function but don’t directly quantify filtration capacity. Bilirubin reflects liver and biliary tract health. HbA1c shows long-term glucose control rather than kidney function.

So the combination of creatinine and eGFR is the best choice for assessing how well the kidneys are functioning.