Serum cystatin C in renal transplant patients.
Assessment of renal function in clinical medicine is of great importance especially in patients with renal transplants. Cystatin C has the characteristics of an ideal marker to assess renal glomerular filtration rate. Forty patients with renal transplants under steady-state post-transplant conditions were included in the study. Steady-state was defined as lack of acute rejection periods during the last 6 months and stable cyclosporin A medication during the past 4 weeks. Gender was balanced with 20 male and 20 female patients, the mean age was 51+/-14 years, time since transplantation was 5+/-3.5 years. Fifteen percent of the patients suffered from diabetes mellitus. Immunosuppression consisted of cyclosporin A, imuran, and prednisolon. To assess renal function cystatin C, creatinine clearance, serum creatinine, and serum beta2-microglobulin were tested. Creatinine was analysed in serum and urine to calculate the creatinine clearance related to 1.73 m(2) body surface. Cystatin C and beta2-microglobulin were determined by using a particle-enhanced turbidimetric assay. Cystatin C correlated best with creatinine clearance (r=0.66), beta2-microglobulin (0.57), and serum creatinine (0.56). The diagnostic accuracy of cystatin C was significantly better than serum creatinine (p<0.05), but did not differ significantly from creatinine clearance (p=0.73), and beta2-microglobulin (p=0.46). Our data show that patients with renal transplants, cystatin C has a similar diagnostic value as creatinine clearance. However, it is superior to serum determination of creatinine and beta2-microglobulin. Cystatin C allows for rapid and accurate assessment of renal function in patients with renal transplants and is clearly superior to the commonly used serum creatinine.
Paskalev
E
E
Department of Nephrology and Kidney Transplantation, Alexandrovska Hospital, 1 G Sofiiski St. 1431 BG, Sofia, Bulgaria.
Lambreva
L
L
Simeonov
P
P
Koicheva
N
N
Beleva
B
B
Genova
M
M
Marcovska
R
R
Nashkov
A
A
D000328:Adult; D000368:Aged; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D005260:Female; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins