Which laboratory value is commonly measured with BUN to assess kidney function?

• A. Glucose
• B. Albumin
• C. Bilirubin
• D. Creatinine

Answer: (D)

Kidney function is best assessed by looking at waste products cleared by the kidneys. BUN measures nitrogen from protein breakdown, but its level can be affected by factors like hydration and liver function, so it isn’t perfectly specific on its own. Creatinine, on the other hand, is produced at a relatively constant rate from muscle metabolism and is filtered by the kidneys; its level rises with decreased glomerular filtration rate, making it a more specific indicator of kidney function. Because clinicians commonly evaluate both, the combination helps distinguish different causes of kidney problems and assess how well the kidneys are filtering.

So, the value commonly measured with BUN to assess kidney function is creatinine. Glucose, albumin, and bilirubin relate more to metabolic status, nutritional status, or liver function, not direct measures of kidney filtration.