Creatinine excretion after renal transplantation

Area of Science:

• Nephrology
• Transplantation Medicine
• Biochemistry

Background:

• Serum creatinine is a common marker for monitoring kidney transplant (allograft) function.
• Accurate interpretation of serum creatinine requires stable urine creatinine excretion.
• The behavior of creatinine excretion in renal transplant recipients is not well understood.

Purpose of the Study:

• To investigate the pattern of creatinine excretion in patients with functioning renal allografts.
• To determine factors influencing creatinine excretion post-transplantation.
• To assess the reliability of serum creatinine for monitoring chronic allograft function.

Main Methods:

• Study included 100 patients surviving at least 12 months post-renal transplantation.
• Creatinine excretion was measured at 3 months and during long-term follow-up (mean 89 months).
• Multivariate analysis examined the impact of patient demographics, clinical factors, and medication on creatinine excretion.

Main Results:

• A progressive decline in creatinine excretion was observed over time post-transplant.
• The greatest decline occurred in patients who later required dialysis.
• Age, sex, weight, obesity, diabetes, and corticosteroid dose significantly influenced creatinine excretion.

Conclusions:

• Creatinine excretion decreases over time in renal transplant recipients, potentially underestimating changes in glomerular filtration rate (GFR).
• Factors affecting muscle mass significantly impact creatinine excretion.
• Reliance solely on serum creatinine may be insufficient for monitoring chronic allograft function; complementary GFR measures are recommended.