Removal of phosphate (Pi) by either bicarbonate dialysis or biofiltration in uremics.

The kinetics of extra and intracellular red blood cell (RBC) Pi and its removal by different therapeutic modalities were evaluated in 30 uremic patients over a 6 mo. period. Acetate hemodialysis alone, combined with hemoperfusion, or associated once a week with plasma-perfusion sessions using an activated bauxite cartridge, bicarbonate dialysis either in single pass or in recirculating system (40 L) and biofiltration, were the depurative treatments employed. The treatments with acetate buffer showed a temporary intracellular shift of Pi at the end of the sessions with post-dialytic plasma Pi rebound. This was not evident with bicarbonate buffer and biofiltration where acidosis was corrected better, and similarly during plasma perfusion treatment because blood pH remained unchanged. These findings may explain the better plasma Pi level at the end of our study with these later therapeutic models compared to acetate dialysis alone or combined with hemoperfusion. In these conditions Pi removal is limited by the correction of acidosis which implies acetate metabolism with ATP activation leading to a transient Pi intracellular influx and a subsequent efflux into the extracellular compartment.

Spontaneous ascites filtration and reinfusion (SAFR) in cirrhotic patients.

Since knowledge about the pathogenesis of hepato-renal syndrome (HRS) is incomplete, the therapy is empiric and supportive. While a number of specific therapeutic measures have been attempted, none has been proved to be of practical value. We describe a very simple technique for concentration of ascitic fluid obtained with spontaneous filtration by gravity. We have been treating with this new device 4 patients affected by HRS with ascites refractory to diuretics. We obtained a rapid disappearance of ascites and improvement in clinical condition. The simplicity and the ease of operation make this technique feasible for repeated chronic ambulatory treatment.

Step-dose of muzolimine at different stages of chronic renal failure: comparison with furosemide.

The authors have compared the clinical and metabolic effects of two high ceiling diuretics, muzolimine (M) and furosemide (F), by i.v. and oral routes in 40 patients classified in four groups with different degrees of renal failure. The study demonstrated a more pronounced effectiveness of M than F by oral administration, while it appeared equal to F when given i.v. The urine volume and Na+ excretion were significantly increased during M treatment compared to oral F in each group. Calcium urinary excretion was reduced with M while P was increased compared with F. BUN, creatinine and uric acid were temporarily increased in the 3rd and 4th groups, probably due to extracellular fluid volume contraction, associated also with transient change in GFR. M at a lower dosage than F has demonstrated an effective diuretic response irrespective the degree of renal impairment. From its pharmacological properties, M appears a safe and active diuretic agent, particularly at a high dosage in patients with severe renal failure, and is notable for its lack of important side effects.

Muzolimine vs. furosemide in nephrotic syndrome: further support of different carrier(s) operating for enteral absorption.

The authors have compared during 4 weeks of study the effects of furosemide (F) by oral route or i.v. and muzolimine (M)/os in 10 patients with nephrotic syndrome (NS) and normal renal function. A satisfactory diuretic response was observed with i.v. F (100 mg) and M/os (30-60 mg) with respect to the basal condition (P less than 0.001), while F/os (100 mg) was ineffective in these patients. This behaviour may be explained by the different pharmacological properties of M vs. F, by gut alterations due to the oedema of mucosa or loss of some "carrier(s)" operating for intestinal absorption of these two high ceiling diuretics.

Spontaneous plasma exchange by gravity.

Lysagth et al have reported a semplified model of spontaneous plasmapheresis by placing between an A-V shunt a conventional plasmafilter. On the basis of this experience we tried to make a further semplification of this apparatus using a single venous puncture, obtaining by gravity sufficient transmembrane pressure for plasma separation. By alternatively lowering and elevating the system, plasma is separated from the blood and packed red cells are reinfused after a new pass through the filter with FFP or plasma substitutes.

Restoration of ultrafiltration capacity of peritoneal membrane in patients on CAPD.

Among 55 uremic patients who entered our CAPD program, 7 of them showed a reduction or loss of the ultrafiltration capacity (UF) of the peritoneal membrane (PM). They have been treated with high dose of Furosemide (F) to force residual urine output. Four appeared "responders" to drug administration with a significant increase in urine volume, Na excretion and, within a week period gained their dry body weight (BW). In the remaining 3 patients drug therapy resulted ineffective, and fluid removal was obtained by hemofiltration (HF). In both groups we noted an increase in the UF capacity of PM when their dry BW was obtained either by pharmacological or technical approach. These results support the assumption that the over-hydration status of the PM plays a major role in maintaining the UF process.

TSH response to TRH in hemodialysis and CAPD patients.

The thyroid status was studied in 19 uremic patients (11 on HD and 8 on CAPD) and in a group of 17 healthy adult patients. In uremic patients T3 and T4 were significantly reduced (p less than 0.001) and rT3 was increased (p less than 0.001). The time course TSH response to TRH showed a lower peak response (in 5 patients it did not exceed 5 microU/ml) which on turn was also delayed (the peak was observed at 60 minutes in 63% of them). TSH concentrations in uremics were increased at 0 time (p less than 0.02), lower at 20 minutes (p less than 0.01) and increased at 120 minutes (p less than 0.02). No difference existed between HD and CAPD. The thyroid response to TSH was normal as showed by a normal percent increase over basal values of T3 concentrations at 120 minutes. Uremic patients also showed a peak GH response at 20 minutes which was not observed in controls. The data exclude the existence on a primary form of hypothyroidism and point to the existence of hypothalamic-pituitary abnormalities, which should not be taken as indicative of secondary and/or tertiary hypothyroidism since FT4 values were normal in HD and increased in patients undergoing CAPD (p less than 0.05) who on turn showed lower plasma albumin concentrations (p less than 0.05).