Total plasma clearance versus urinary plasma clearance of (51)Cr-EDTA in patients with cirrhosis with and without fluid retention

AbstractBackground and aim. In patients with fluid retention, the total plasma clearance of 51Cr-EDTA (ClP) may overestimate the glomerular filtration rate (GFR). The present study was therefore undertaken in order to compare ClP with the urinary plasma clearance of 51Cr-EDTA (ClU) in patients with cirrhosis with and without fluid retention. Material and methods. A total of 136 patients with cirrhosis (24 without fluid retention, 112 with ascites) received a quantitative intravenous injection of 51Cr-EDTA followed by plasma and quantitative urinary samples for 5 hours. ClP was determined from the injected dose relative to the plasma concentration-time area, extrapolated to infinity. ClU was determined as urinary excretion relative to the plasma concentration-time area up to voiding. Results. In patients without fluid retention, the difference between ClP and ClU (ClP − ClU = ClΔ) was mean 4.5 mL/min/1.73 m2. In patients with ascites, ClΔ was significantly higher (17.6 mL/min/1.73 m2, p < 0.0001). ClΔ incr...