A comparison of the effects of glucose ingestion and NH4Cl acidosis on urinary calcium and magnesium excretion in man.

Both glucose ingestion and NH(4)Cl acidosis have been reported to augment urinary calcium (U(Ca) V) and magnesium (U(Mg) V) excretion. Both also cause acidification of the urine and an increase in renal acid excretion. To examine whether a common mechanism of action was involved, the effects of glucose ingestion and NH(4)Cl acidosis on U(Ca) V and U(Mg) V were tested in the same subjects. Glucose ingestion caused significant increases in both U(Ca) V and U(Mg) V. During stable NH(4)Cl acidosis, U(Ca) V increased significantly, while U(Mg) V was unaffected. When a glucose load was given during acidosis, the separate effects of acidosis and glucose on U(Ca) V were additive, whereas U(Mg) V increased less than observed during normal acid-base balance. Although renal acid excretion increased and the urine was acidified after glucose in the normal steady state, when glucose was administered during NH(4)Cl acidosis urine pH rose and there was no change in renal acid excretion. We concluded that NH(4)Cl acidosis and glucose ingestion reduce the renal tubular reabsorption of magnesium and (or) calcium, but they act through separate mechanisms.

The effect of glucose on urinary cation excretion during chronic extracellular volume expansion in normal man.

Both glucose administration and extracellular volume expansion augment urinary calcium and magnesium excretion. While volume expansion also augments sodium excretion, glucose induces an antinatriuresis. To examine the interrelationships of volume expansion and of glucose administration on sodium, calcium, and magnesium excretion, the effects of glucose were evaluated during clearance studies in the same subjects before and after chronic extracellular volume expansion produced by desoxycorticosterone acetate (DOCA) and a normal dietary sodium intake. The augmentation of U(Ca)V and U(Mg)V by glucose was simply additive to the increments in divalent cation excretion caused by "escape" from the sodium-retaining effects of DOCA. Glucose administration reduced U(Na)V, an effect exaggerated after DOCA escape and associated with reductions in volume/glomerular filtration rate (V/GFR) and C(Na) + C(H2O)/GFR, suggesting augmented proximal tubular reabsorption. Before glucose, U(Na) was inversely correlated with U(G), and after glucose administration C(Na)/GFR was inversely correlated with T(G)/GFR. We propose that the availability of glucose in the proximal tubule stimulates Na reabsorption while delaying development of a chloride diffusion potential, thereby inhibiting tubular reabsorption of Ca and Mg.

Infantile polycystic kidney disease in the adult.

We evaluated an adult with polycystic kidney disease that had been present since birth. Our evidence indicates that this patient is a unique example of survival into adult life of the recessively inherited, infantile form of polycystic kidney disease.

Effect of glucocorticoids on WBC counts in splenectomized renal transplant recipients.

Change in peripheral blood WBC and differential cell count in response to oral glucocorticoids (steroids) was examined in 36 stable renal transplant patients receiving their usual steroid dose on a daily or alternate-day steroid schedule. Three hours following steroid therapy mean WBC count had increased significantly. Mean change in WBC count was +2,400 cells/cu mm with individual values ranging from -600 to +8,000/cu mm. No differences were observed between patients receiving daily or alternate-day regimens. Changes in WBC count were due almost entirely to an increase in segmented granulocytes and a decrease in lymphocytes. there was no correlation between dose of steroid and WBC responses. However, when retested, a given patient's WBC response to a given dose of steroid was reproducible. Differences between patients, with respect to WBC response to steroids, could not be explained by differences in azathioprine dose and was not related to initial WBC count hematocrit value, age, duration of transplant, or levels of serum creatinine, BUM, or serum phosphorus. Because of the clinical importance of the WBC count in the renal transplant recipient and the potential for large and unpredictable changes in WBC count in response to steroids, WBC and differential cell count should be obtained before the morning steroid dose.

Habitual excessive dietary salt intake and blood pressure levels in renal transplant recipients.

We observed that renal transplant recipients with good graft function (mean serum creatinine level 1.5 mg/dl +/- 0.5 SD, N = 68) had dietary salt intakes (estimated from serial measurements of 24-hour sodium excretion rate) which averaged 43 percent higher than that of a comparable group of healthy subjects. There was no correlation between blood pressure levels and salt intake and, despite the high dietary salt intake, hypertension was present in only 29 patients and was usually mild; mean systolic and diastolic blood pressures were 132 +/- 10 mm Hg and 89 +/- 7 mm Hg, respectively while the patients were receiving antihypertensive medication (median number of standard doses of antihypertensive medication was 1.0 doses/patient patient per day). These observations suggest that high dietary salt intake does not exert a powerful blood pressure elevating effect, since any effect of high dietary salt intake to raise blood pressure should have been magnified in the renal transplant recipients because of their reduced renal mass and their chronic glucocorticoid therapy.

Plasma dopamine-beta-hydroxylase in uremia--increase in enzyme activity after renal transplantation.

Plasma dopamine-beta-hydroxylase in uremia. Plasma dopamine-beta-hydroxylase (DBH) activity was found to be low in 26 uremic patients when compared with 56 normal individuals (p less than 0.001). Hemodialysis caused only a slight increase in plasma DBH levels in the uremic group. In contrast, a group of kidney transplanted patients with a return of good renal function had DBH values similar to the normal group (p greater than 0.1). The mean plasma DBH activity in eight patients measured pre- and post-transplantation increased from 4.5 to 28 International Units/l (p less than 0.01). No evidence was found to indicate that the depressed levels of plasma DBH in uremia were secondary to genetic or enzyme inhibiting factors. It is suggested that low levels of DBH activity in patients with renal failure may be a consequence of altered sympathetic nervous activity which is known to occur in the uremic state.

A method to assess efficacy of CAPD: preliminary results.

Adequacy of dialysis is a primary concern when caring for patients undergoing continuous peritoneal dialysis (CAPD). To determine objectively the efficacy of CAPD, the use of an 'efficacy number' (EN) calculated from the data obtained in a peritoneal equilibration test (PET) for creatinine (cr) is proposed: EN = [cr(D/P) x V24] divided by ACPPD3 Where, cr(D/P) is PET-derived dialysate/plasma ratio for creatinine at 4 hrs; V24 is the volume of exchanges (L) prescribed for 24 hrs; ACPPD is adjusted creatinine production based on daily dialysate creatinine appearance. PET were performed and the EN calculated in two groups of CAPD patients observed over a 10 month period. One group (n = 8) had a poor clinical outcome in terms of uremic parameters. The EN in this group was 3.85 +/- 0.45 (+/- 1 SD) L/g creatinine/day. The other group (n = 4) was considered well dialyzed and had a good clinical outcome over 10 months. The EN in this group was 6.07 +/- 0.40 L/g creatine/day, p less than 0.001. There was no statistically significant difference between the two groups in regard to sex, age, length of time on dialysis, underlying kidney disease, baseline creatinine, or D/P ratios of creatinine and BUN. The 'efficacy numbers' appears to be more useful than the D/P ratio alone in determining the adequacy of CAPD. A simple to use nomogram is presented which provides guidelines for the clinician to alter the dialysis prescription.

Ureteral stenosis due to recurrent Wegener's granulomatosis after kidney transplantation.

The ureter is an unusual location for lesions of Wegener's granulomatosis (WG). A patient in whom recurrence of WG after kidney transplantation was manifested by obstructive uropathy due to granulomatous vasculitis (WG) at the ureterovesicle anastomosis, as well as nasal and lung involvement, is reported. The occurrence of WG in the ureter in relation to the processes causing ureteral obstruction and the recurrences of WG after kidney transplantation and its treatment are briefly reviewed.

Role of the clinical laboratory in guiding treatment of Amanita virosa mushroom poisoning: report of two cases.

Historically, mortality after Amanita mushroom ingestion has ranged from 50% to 90%. Prompt diagnosis is imperative, and aggressive therapeutic measures must be instituted quickly to improve the outcome. We report successful treatment of two cases of A. virosa poisoning by use of combined therapies, including thioctic acid and hemoperfusion.

Mechanisms producing hypoxemia during hemodialysis.

Arterial hypoxemia occurs frequently during hemodialysis. Proposed mechanisms for this phenomenon have included hypoventilation and embolism of granulocyte aggregates. We studied 18 patients with endstage renal failure who required chronic hemodialysis, and measured arterial blood gases, pulmonary gas exchange, and dialyzer gas exchange. During use of acetate as a dialysate buffer, PaO2 decreased to 80 +/- 6.8 torr, whereas during use of the bicarbonate buffer oxygen tension remained at 92 +/- 4.9 torr or greater. Hypoventilation and microembolism were not sufficient to explain the degree of hypoxemia during acetate dialysis. Hypoxemia occurred only after the 1st exposure to acetate; neither an instantaneous change to bicarbonate nor stopping dialysis restored oxygen tension to normal. We conclude that a pharmacologic action of acetate adversely affects lung function, aggravating the decreased alveolar oxygen tension (PAO2) due to hypoventilation. Hypoxemia was not present when bicarbonate was used. Acetate buffer should not be used for dialysis in patients with unstable cardiovascular or respiratory systems.

Determinants of dialyzer reuseability.

The authors observed a wide variability in the number of uses per dialyzer in their hemodialysis patients. In 54 patients who reused their dialyzers, heparin dose (U/kg/min) related directly and white blood cell count related inversely to reuseability. Average reuse was 5.1 +/- 2.9 (SD) in diabetics (n = 13) and 7.8 +/- 3.8 (SD) in non-diabetics (n = 41; p = 0.007). Of the diabetics, 77% achieved six or less reuses, and 59% of non-diabetics achieved six or more reuses (chi-square = 4.96; p less than 0.05). In non-diabetics, heparin dose was the most significant determinant of reuse, and in diabetics the major determinant was white blood cell count. Hematocrit levels, platelet count, erythropoietin use, or type of membrane (polysulfone/cellulose acetate) did not correlate with reuseability. It was concluded that reuseability of dialyzers is less in diabetic patients, patients on lower heparin doses (U/kg/min), and patients with higher white blood cell counts. Determinants of dialyzer reuseability warrant further study.

Rapidly progressive glomerulonephritis superimposed on diabetic glomerulosclerosis. Recognition and treatment.

Two patients with long-standing diabetes mellitus and diabetic retinopathy were evaluated for declining renal function and heavy albuminuria. Initially, diabetic glomerulosclerosis was suspected as the cause of progressive glomerulopathy. However, in both patients the rate of loss of glomerular filtration rate was greater than that usually seen in diabetic glomerulosclerosis, and the urine sediment contained many RBC casts. These findings led to renal biopsy, which demonstrated crescentic glomerulonephritis superimposed on diabetic glomerulopathy. Both patients were treated with prednisone and cyclophosphamide and both experienced substantial improvement in renal function. These experiences demonstrate the importance of searching for evidence of a superimposed treatable glomerulopathy in the diabetic patient with glomerulopathy and advancing renal insufficiency.

Successful second kidney transplantation in a patient with focal glomerulosclerosis. A case report.

We report a woman who developed renal failure due to focal glomerulosclerosis (FGS). This disease recurred immediately in a kidney transplant from her brother resulting in removal of that graft. She subsequently received a cadaver kidney transplant, and FGS has not recurred after 24 months. This is the first report of nonrecurrence in a second kidney graft, when the first was lost due to recurrent FGS. Whether timing or tissue typing of the second graft in relationship to the first is important is not known. Recurrence of FGS in a first kidney graft should not, however, preclude future transplantation.

Clinical outcome of continuous ambulatory peritoneal dialysis predicted by urea and creatinine kinetics.

The effectiveness of urea kinetics (Kt/V, where K is urea clearance, t is treatment time, and V is the volume of distribution for urea) to assess the adequacy of continuous ambulatory peritoneal dialysis (CAPD) and clinical outcome has not been established prospectively, and cross-sectional clinical studies have been inconclusive. A minimum weekly creatinine clearance of 40 to 50 L is recommended, but the adequacy of this dose is unproven. We introduced a simpler approach to creatinine kinetics in the form of an efficacy number (EN) calculated from data obtained in a standardized 4-h dwell exchange. To determine the most effective model for predicting CAPD adequacy, residual renal function, weekly Kt/V urea, weekly creatinine clearance standardized to body surface area, and EN (liters per gram of creatinine per day) were measured in 18 stable CAPD patients followed prospectively for at least 12 months. Patients were divided into three groups, good (G), intermediate (I), and poor (P), on the basis of uremic symptoms, mortality, hospital days, biochemical indices, and the need for transfer to hemodialysis. When comparing groups G (N = 6) and P (N = 8), weekly Kt/V were 2.3 +/- 0.2 versus 1.5 +/- 0.1 (P less than 0.005), weekly creatinine clearances were 71.5 +/- 8.6 versus 35.1 +/- 1.3 L (P less than 0.001), and EN were 7.4 +/- 0.8 versus 3.6 +/- 0.2 L/g of creatinine/day (P less than 0.005). Creatinine kinetics (weekly clearance and EN) but not urea kinetics could differentiate group I (N = 4) from groups G or P. Both urea and creatinine kinetics predict clinical outcome in CAPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Pneumococcal vaccine immunization of patients with renal impairment.

The immunogenicity of the polyvalent pneumococcal vaccine was studied in renal allograft recipients and dialysis patients. There was no significant overall difference in the antibody response of the allograft recipients compared to control subjects at 1 month following immunization. Chronic hemodialysis patients had significantly lower postvaccination antibody levels for 6 of 12 serotypes. Better graft function in the allograft recipients correlated positively with higher antibody levels. Azathioprine and prednisone in dosages employed had no consistent effect on antibody response. No deterioration of renal function ascribable to the vaccine was observed. Patients were sampled at 1, 2, and 3 1/2 years following immunization. Geometric mean titers (GMT) were calculated for all the serotypes per group for each time of sampling. There was a significant decrease with time in antibody GMTs for all the groups (P less than 0.01). Chronic hemodialysis patients had significantly lower GMTs than control subjects and allograft recipients at 1, 2, and 3 1/2 years postimmunization (P less than 0.05). The 3 1/2 years postimmunization antibody levels were very low in dialysis patients, suggesting that reimmunization of these patients may be required.

Inflow time and recirculation in single-needle hemodialysis.

The recirculation of previously dialyzed blood in the lumen of the single-needle catheter reduces dialysis efficiency and is a drawback of single-needle dialysis. We reasoned that using maneuvers that would augment the volume of blood drawn in during the inflow phase of each dialytic cycle would decrease recirculation. We tested this hypothesis by progressively lengthening the inflow time and measuring the recirculation rate in three patients undergoing single-needle hemodialysis with a single-lumen subclavian hemodialysis catheter during five separate dialyses. Inflow time was varied with a time-time single-needle device (Gambro SN-10-2D). Percentage recirculation decreased progressively from 23% +/- 3% at an inflow time of 1 second to 7% +/- 2% at an inflow time of 4 seconds (P less than .03, n = 5). With a time-time single-needle device, recirculation did not vary, with a change in pump speed from 106 to 250 mL/min (8.2% v 8.4%, n = 6). With other single-needle devices, however, inflow time varied inversely with pump speed, and at higher pump speeds, recirculation tended to increase, although not uniformly, in every patient. Maximizing the inflow volume is essential for minimizing recirculation in single-needle hemodialysis. Clinically insignificant recirculation ensues when inflow time is maintained between 3 to 5 seconds and time-time single-needle devices are used, even in patients dialyzed with single-lumen subclavian catheters.

Acute motor paralytic bladder in renal transplant patients with anogenital herpes infection.

We report on 2 renal transplant patients in whom acute urinary retention developed after anogenital herpes infections. In 1 case a reversible bladder motor and sensory neuropathy occurred secondary to herpes simplex virus infections. In the other case a motor paralytic bladder developed secondary to an anogenital varicella-zoster infection. Documentation was by carbon dioxide cystometrography and denervation hypersensitivity testing. Both cases were reversible without alteration of the immunosuppressive regimens.

End-stage renal disease (ESRD)after bone marrow transplantation: poor survival compar ed to other causes of ESRD.

Chronic renal failure after successful bone marrow transplantation (BMT) may diminish the quality of life and may also evolve to end-stage renal disease (ESRD) requiring chronic dialysis. Individual reports suggest poor survival of such patients. We evaluated the survival with ESRD after BMT by the case-control method. We found that patients who develop ESRD after BMT have a significantly decreased survival as compared with non-BMT patients. This was true for both diabetic and nondiabetic ESRD (both p < 0.03). These data demonstrate the poor outcome of ESRD after BMT which emphasizes the need for a better understanding of chronic renal failure after BMT.

Preeclampsia related to a functioning extrauterine placenta: report of a case and 25-year follow-up.

We report the case of a patient with preeclampsia due to an extrauterine, intra-abdominal pregnancy. After the fetus was delivered, but while the functioning placenta remained in the abdomen, preeclampsia, which was documented by clinical data and a kidney biopsy, persisted until the placenta was removed 99 days postpartum. A kidney biopsy 21 months postpartum was normal. Twenty-five years later, her kidney function and blood pressure were normal. The observation of this patient supports the view that the placenta must be intact for the development of preeclampsia and is the first description of endotheliosis in a kidney biopsy from a hypertensive woman with an intra-abdominal pregnancy.