Coadministration of albumin and furosemide in patients with the nephrotic syndrome

Background. In patients with nephrotic syndrome, the natriuretic effect of furosemide (FU) is diminished. The effect of coadministration of FU and hum an albumin (HA) has remained controversial. Methods. In a double-blind, placebo-controlled study, nine nephrotic patien ts (six males, 48 +/- 4 years) on standardized sodium chloride intake, in r andom order on three separate days, received by intravenous administration for 60 minutes either (a) 60 mg FU plus a sham infusion, (b) 60 mg FU plus 200 mi of a 20% solution of HA, or (c) sham infusion plus 200 mi of a 20 % solution of HA. Urinary volume, sodium, albumin and FU excretion, renal hem odynamics, and plasma atrial natriuretic factor concentration were assessed . Results. Administration of FU alone significantly (P < 0.01) increased mean cumulative urinary sodium (259 +/- 30 mmol) and volume excretion (2684 +/- 167 mi) in the first eight hours as compared with the HA infusion alone (1 18 +/- 12 mmol, 1827 +/- 141 mi). The coadministration of FU and HA caused an even more marked increase (P < 0.01 vs. HA alone) of urinary sodium (312 +/- 28 mmol) and volume excretion (3230 +/- 201 mi); the difference to FU administration alone was significant (P < 0.05). Plasma atrial natriuretic factor, serum albumin concentration, and urinary albumin excretion increase d significantly on both HA infusion days, whereas urinary excretion of FU r emained unchanged with HA coadministration. Glomerular filtration rate (C-l n) was not significantly affected by any of the infusion protocols, but eff ective renal plasma flow (C-PAH) increased significantly on both HA infusio n days. Conclusions. Coadministration of HA potentiates the action of FU in patient s with the nephrotic syndrome, but only modestly. This effect is mediated b y changes in renal hemodynamics.