Cystatin C and renal function in pediatric kidney transplant recipients

Area of Science:

• Nephrology
• Pediatric medicine
• Clinical chemistry

Background:

• Serum creatinine is commonly used to estimate glomerular filtration rate (GFR) in clinical practice.
• Cystatin C is emerging as a more sensitive biomarker for detecting impaired renal function.
• Accurate GFR assessment is crucial for managing pediatric kidney transplant recipients.

Purpose of the Study:

• To compare estimated GFR (eGFR) using plasma cystatin C versus serum creatinine in pediatric kidney transplant recipients.
• To evaluate the diagnostic performance of cystatin C for identifying reduced GFR in this population.
• To determine if cystatin C reveals a higher prevalence of chronic kidney disease (CKD) in pediatric kidney transplant recipients.

Main Methods:

• Cross-sectional study comparing eGFR derived from serum creatinine and plasma cystatin C.
• Inclusion of 50 pediatric renal transplant recipients and 24 healthy children.
• Statistical analysis including Pearson's correlation to assess the relationship between the two methods.

Main Results:

• A significant correlation (r = 0.75, P < 0.001) was observed between eGFR estimated by serum creatinine and cystatin C.
• In pediatric kidney transplant recipients, eGFR was consistently lower by 6.7 mL/min when using cystatin C compared to serum creatinine.
• Using cystatin C, 42% of recipients had eGFR <60 mL/min/1.73 m², versus only 16% when using serum creatinine (P < 0.001).

Conclusions:

• In pediatric kidney transplant recipients, cystatin C-based GFR estimation yields lower values than serum creatinine-based estimation.
• Cystatin C identifies a significantly higher proportion of pediatric kidney transplant recipients with eGFR indicative of chronic kidney disease.
• These findings suggest cystatin C may be a more sensitive marker for detecting impaired kidney function post-transplantation in children.