We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Albuminuria increases cystatin C excretion: implications for urinary biomarkers.
- Authors
Nejat, Maryam; Hill, Jonathan V.; Pickering, John W.; Edelstein, Charles L.; Devarajan, Prasad; Endre, Zoltán H.
- Abstract
Background Low-molecular weight (LMW) proteins, including albumin and novel urinary biomarkers of acute kidney injury (AKI) such as cystatin C and neutrophil gelatinase-associated lipocalin (NGAL), are normally absorbed from the glomerular filtrate by receptor-mediated transport. We evaluated the effect of albuminuria on urinary excretion of novel biomarkers. Methods Sprague–Dawley rats given four injections over 2 days of 5 mg/g body wt/day bovine serum albumin (BSA) in saline were compared with controls given saline alone. Urinary cystatin C, albumin and protein excretion rates were compared prior to treatment (Day −1), after treatment (Day 2) and 4 days later (Day 6). A preliminary assessment of the clinical effect of proteinuria on the filtered urinary biomarkers cystatin C and NGAL was made by comparison with the effect on urinary interleukin-18 (IL-18) that is not absorbed from the glomerular filtrate, in a cohort of intensive care unit patients. Results BSA induced transient increases in albuminuria, proteinuria and cystatinuria (P < 0.01, P < 0.001 and P < 0.001, respectively). Beyond a threshold 6-fold increase in albuminuria, cystatin C absorption was reduced by competitive inhibition. The excretion rates of all analytes returned to preinjection levels by Day 6. Clinical proteinuria was associated with increasing cystatin C and NGAL concentrations (n = 90, P < 0.0001) but not IL-18 (P = 0.12). Conclusions Proteinuria may increase the threshold for detection of AKI by increasing the excretion of LMW protein biomarkers.
- Subjects
ALBUMINURIA; CYSTATINS; EXCRETION; BIOMARKERS; KIDNEY injuries; ALBUMINS; NEUTROPHILS; GELATINASES
- Publication
Nephrology Dialysis Transplantation, 2012, Vol 27, Issue suppl_3, piii96
- ISSN
0931-0509
- Publication type
Article
- DOI
10.1093/ndt/gfr222