Comparison of markers of circulating blood volume in hemodialysis patients.

BACKGROUND: Pulse dye-densitometry (PDD) is a newly developed technique for monitoring the arterial concentration of indocyanine green (ICG). By using this method, the circulating blood volume (CBV) can be measured as accurately as by established dilution methods using (131)I-labeled human serum albumin in healthy subjects. In the present study, we estimated the CBV in hemodialysis (HD) patients, using PDD, and compared the utility of this method with that of other markers of the CBV. METHODS: We measured the CBV in seven HD patients and eight healthy volunteers, using PDD, and evaluated the correlation between the CBV measured by PDD (CBV-PDD) and the calculated CBV (CBV-Cal), using a prediction formula (CBV (l) = 2.68 x BSA, where BSA is body surface area (m(2))). We also investigated the correlation between CBV-PDD and the maximal inferior vena cava diameters in quiet expiration (IVCe), and the plasma levels of atrial and brain natriuretic peptides (ANP and BNP, respectively) in the HD patients. RESULTS: CBV-Cal was closely correlated with CBV-PDD in the healthy volunteers, but there was no such correlation in the HD patients. On the other hand, IVCe was significantly correlated with the CBV-PDD in the healthy volunteers as well as in HD patients. ANP and BNP were not correlated with the CBV-PDD in the HD patients. CONCLUSIONS: We concluded that CBV-PDD and IVCe were useful parameters in evaluating the CBV in HD patients, while CBV-Cal was not a useful parameter. Also, as a marker of changes in the CBV in HD patients, IVCe was considered to be more sensitive than either ANP or BNP.

Rapid and persistent reduction of proteinuria following plasma exchange in a case of steroid-resistant focal segmental glomerulosclerosis.

We report on the case of a 45 year old male with focal segmental glomerulosclerosis (FSGS) in whom steroid-resistant proteinuria was reduced rapidly by plasma exchange. In 1994, he was admitted to our hospital because of massive proteinuria of several years' duration. Renal biopsy confirmed the diagnosis of FSGS. Proteinuria was suppressed partially with the use of dipyridamole. Though oral prednisolone (PSL, 30 mg/day) was effective initially, relapse occurred during PSL tapering. Doses of PSL up to 30 mg/day or additional mizoribine were ineffective. The patient was readmitted for a trial of plasma exchange in April 2000. Four sessions of plasma exchange with albumin replacement over 2 weeks immediately reduced the proteinuria from 3.2 g/day to 0.6 g/day without any change in medication. After discharge, proteinuria remained suppressed for more than 6 months despite a reduction of PSL dose to 15 mg. The rapid and long lasting effect of plasma exchange in the present case argues for the role of a putative circulatory factor in the pathogenesis of proteinuria in FSGS.