Impaired response to intrarenal administered atrial natriuretic peptide in ischemic acute renal failure of a transplanted patient.

A 30-year-old male patient suffering from membrano-proliferative glomerulonephritis was transplanted a cadaveric kidney 3 years ago. Five days later the transplant was removed because of fresh thrombosis in larger arteries. Three years after first transplantation a second graft was transplanted. Repeated perfusion scintigraphies of persistent anuric patient showed a delayed perfusion of renal parenchyma, no intrarenal bolus was obtained. Urgently, an arterial angiography was performed. It demonstrated that calibers of renal parenchymal vasculature were narrowed. Suggesting ischemic nature of acute renal failure, 50 micrograms human atrial natriuretic peptide (hANP) was injected intrarenally as bolus. Five minutes after hANP injection in a second angiography a significant improvement of renal blood flow was demonstrated but no amelioration of urine production or electrolyte excretion was observed. Histologically an ischemic lesion of transplant was proven. This finding indicates a blunted excretory response of acute renal failure after kidney transplantation despite of significantly ameliorated renal blood flow visualized radiologically.

Clinical evaluation of a new high-flux cellulose acetate membrane.

One major goal of dialysis therapy has become the removal of beta 2-microglobulin (beta 2-m). The interdialytic elimination of beta 2-m was studied using a newly developed high-flux cellulose acetate (CA) membrane. The results show that high-flux CA dialyzers offer better biocompatibility than classical Cuprophan or high-flux Cuprophan devices, with regard to leukopenia, C3a desarg generation, and elastase release from polymorphonuclear (PMN) leukocytes. Compared to high-flux CA membranes, high-flux PMMA membranes induce less C3a desarg formation but comparable leukopenia. High-flux PMMA membranes, however cause greater leukocyte stimulation than CA as demonstrated by more PMN elastase release during hemodialysis. Using high-flux CA or high-flux PMMA membranes, serum beta 2-m levels decreased 32% during dialysis. Serum beta 2-m dropped 10% with high-flux Cuprophan membranes, but remained unchanged with conventional Cuprophan dialyzers. Sieving coefficients for beta 2-microglobulin (beta 2-m) were virtually zero with classical Cuprophan and 0.66 with high-flux cellulose acetate membranes. High-flux membranes made of Cuprophan and PMMA gave coefficients of 0.25 and 0.45, respectively. This indicates the high removal capacity of the new CA-membrane for substances with high molecular weight. This high-flux CA membrane thus appears to combine a good degree of biocompatibility with a high capacity for beta 2-m removal.