Open AccessEvaluation of Cystatin C for the Detection of Chronic Kidney Disease in Cats
Author(s) -
Ghys L.F.E.,
Paepe D.,
Lefebvre H.P.,
Reynolds B.S.,
Croubels S.,
Meyer E.,
Delanghe J.R.,
Daminet S.
Publication year - 2016
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/jvim.14256
Subject(s) - medicine , cats , cystatin c , kidney disease , creatinine , gastroenterology , renal function , urology , pathology
Background Serum cystatin C ( sC ysC) and urinary cystatin C ( uC ysC) are potential biomarkers for early detection of chronic kidney disease ( CKD ) in cats. An in‐depth clinical validation is required. Objectives To evaluate CysC as a marker for CKD in cats and to compare assay performance of the turbidimetric assay ( PETIA ) with the previously validated nephelometric assay ( PENIA ). Animals Ninety cats were included: 49 CKD and 41 healthy cats. Methods Serum CysC and uC ysC concentrations were prospectively evaluated in cats with CKD and healthy cats. Based on plasma exo‐iohexol clearance test (Pex ICT ), sC ysC was evaluated to distinguish normal, borderline, and low GFR . Sensitivity and specificity to detect Pex ICT < 1.7 mL /min/kg were calculated. Serum CysC results of PENIA and PETIA were correlated with GFR . Statistical analysis was performed using general linear modeling. Results Cats with CKD had significantly higher mean ± SD sC ysC (1.4 ± 0.5 mg/L) ( P < .001) and uC ysC/urinary creatinine ( uC r) (291 ± 411 mg/mol) ( P < .001) compared to healthy cats ( sC ysC 1.0 ± 0.3 and uC ysC/ uC r 0.32 ± 0.97). UC ysC was detected in 35/49 CKD cats. R 2 values between GFR and sC ysC or sC r were 0.39 and 0.71, respectively ( sC ysC or sC r = μ + GFR + ε). Sensitivity and specificity were 22 and 100% for sC ysC and 83 and 93% for sC r. Serum CysC could not distinguish healthy from CKD cats, nor normal from borderline or low GFR, in contrast with sC r. Conclusion Serum CysC is not a reliable marker of reduced GFR in cats and uC ysC could not be detected in all CKD cats.