Which laboratory finding would most strongly indicate possible graft dysfunction in a renal transplant recipient?

Which laboratory finding would most strongly indicate possible graft dysfunction in a renal transplant recipient?

• A. BUN 56 mg/dL and creatinine 1.9 mg/dL.
• B. Hemoglobin 9.6 g/dL.
• C. Temperature 100.6° F.
• D. Potassium 4.2 mEq/L.

Answer: (A)

The key idea is that a rising level of kidney filtration markers indicates graft dysfunction. Serum creatinine is the most specific indicator of how well the transplanted kidney is filtering. When creatinine increases, it means the glomerular filtration rate has dropped, suggesting possible graft problems such as rejection, acute tubular injury, or impaired perfusion. A BUN that is elevated alongside an increased creatinine supports reduced kidney function, and in a transplant recipient this pattern is especially concerning for graft dysfunction. In this scenario, the combination of a BUN of 56 mg/dL with a creatinine of 1.9 mg/dL points to impaired renal function of the transplanted kidney and would prompt further evaluation of graft status. The other findings are less specific for graft dysfunction. A low hemoglobin can result from anemia of various causes and doesn’t directly indicate the graft’s filtering ability. A mild fever is nonspecific and could reflect infection or other issues, not a direct measure of graft function. A normal potassium level does not indicate dysfunction; potassium disturbances can occur with kidney injury but aren’t definitive on their own.

The key idea is that a rising level of kidney filtration markers indicates graft dysfunction. Serum creatinine is the most specific indicator of how well the transplanted kidney is filtering. When creatinine increases, it means the glomerular filtration rate has dropped, suggesting possible graft problems such as rejection, acute tubular injury, or impaired perfusion. A BUN that is elevated alongside an increased creatinine supports reduced kidney function, and in a transplant recipient this pattern is especially concerning for graft dysfunction.

In this scenario, the combination of a BUN of 56 mg/dL with a creatinine of 1.9 mg/dL points to impaired renal function of the transplanted kidney and would prompt further evaluation of graft status.

The other findings are less specific for graft dysfunction. A low hemoglobin can result from anemia of various causes and doesn’t directly indicate the graft’s filtering ability. A mild fever is nonspecific and could reflect infection or other issues, not a direct measure of graft function. A normal potassium level does not indicate dysfunction; potassium disturbances can occur with kidney injury but aren’t definitive on their own.