The nurse reviews the kidney function blood studies of four clients. Which client's results indicate kidney impairment?

The nurse reviews the kidney function blood studies of four clients. Which client's results indicate kidney impairment?

• A. Client 1: Serum Creatinine 0.1 mg/dL; BUN 16 mg/dL
• B. Client 2: Serum Creatinine 0.8 mg/dL; BUN 18 mg/dL
• C. Client 3: Serum Creatinine 1.2 mg/dL; BUN 20 mg/dL
• D. Client 4: Serum Creatinine 1.9; BUN 22 mg/dL

Answer: (D)

Elevated serum creatinine is the clearest sign of reduced kidney filtration. Creatinine is produced at a nearly constant rate and is normally cleared by the kidneys; when glomerular filtration drops, creatinine accumulates in the blood. BUN can rise for several non-kidney reasons (dehydration, high protein intake, catabolic states), so it’s a less specific marker. In these values, the first three clients have creatinine levels within or near the normal range, while the fourth client has a markedly elevated creatinine of 1.9 mg/dL with a modestly increased BUN of 22 mg/dL. This pattern points to impaired kidney function, since the high creatinine directly reflects reduced filtration rather than a transitory or non-renal factor.

Elevated serum creatinine is the clearest sign of reduced kidney filtration. Creatinine is produced at a nearly constant rate and is normally cleared by the kidneys; when glomerular filtration drops, creatinine accumulates in the blood. BUN can rise for several non-kidney reasons (dehydration, high protein intake, catabolic states), so it’s a less specific marker.

In these values, the first three clients have creatinine levels within or near the normal range, while the fourth client has a markedly elevated creatinine of 1.9 mg/dL with a modestly increased BUN of 22 mg/dL. This pattern points to impaired kidney function, since the high creatinine directly reflects reduced filtration rather than a transitory or non-renal factor.