William H. Bay

The Living Donor in Kidney Transplantation

Kidney transplantation using either kidneys from living or nonliving donors is now generally regarded as the primary therapy for most patients with end-stage kidney failure. In 1984, 32% of all kidney transplantations done in the United States involved living donors. Reasons justifying the use of kidneys from living donors are the higher success rate and the inadequate supply of cadaveric kidneys. In addition, with a living donor, it is easier to arrange for kidney transplantation before dialysis therapy needs to be started. An analysis of 2495 donor nephrectomies reported in the literature, and 5698 donor nephrectomies reported from the 12 largest centers that do kidney transplantation with living donors, indicates an approximate incidence of 1 donor death per 1600 nephrectomies. Although long-term follow-up in kidney donors has shown only that mild, nonprogressive proteinuria develops in about 33% and that the frequency of hypertension may increase, we advise that the kidney donor have a careful long-term follow-up and avoid a high protein intake because of its potential to lead to progressive glomerular damage.

The Hemodialysis Access: Preferences and Concerns of Patients, Dialysis Nurses and Technicians, and Physicians

One hundred twenty-eight hemodialysis patients and 64 medical personnel consisting of dialysis nurses and technicians, hemodialysis access surgeons and nephrologists were surveyed about their preferences and concerns in regard to the hemodialysis vascular access. The access preferred by physicians was the A-V fistula in the lower arm. In contrast, the access preferred by dialysis nurses and technicians was the polytetrafluoroethylene (PTFE) graft in the lower arm. Patients desired a superficial access in the forearm which was easy to cannulate, had minimal effect on their appearance, provided quick hemostasis after dialysis and enabled arm comfort during dialysis. Physicians felt the most significant concerns about the access were thrombosis and infection. Nurses and technicians ranked difficult cannulation and insufficient access blood flows that prohibited dialysis adequacy as their major problems. For patients the most common problem was pain during needle insertion. This survey concluded that the A-V fistula remains the access of choice. However, appropriate maturation of the fistula must occur before needle insertion is attempted. An immature fistula is difficult to cannulate, has fragile veins resulting in blood leakage around the needle infiltrating the subcutaneous tissues and has inadequate blood flows for successful dialysis. Patients who are introduced to dialysis with inadequate access function or access failure from either an A-V fistula or a PTFE graft have increased morbidity, inadequate dialysis and enhanced anxiety about dialysis treatments. To increase the success and acceptance of A-V fistulas in hemodialysis patients it is incumbent upon the nephrologist to protect the future access arm from damage to the vasculature and to allow for fistula maturation before cannulation. Surgical protocols must improve the appropriate selection of a fistula or PTFE graft for various age groups and disease categories. Better patient preparation and selection of the proper access type for each patient will enhance early access function and subsequent access survival.

The Gore-Tex® Peritoneal Catheter: A Clinical Evaluation and Comparison With the Tenckhoff Catheter

In January of 1983, the Gore-Tex (W.L. Gore & Associates, Inc, Flagstaff, Ariz) peritoneal catheter was introduced into the dialysis market. Presently, there is no other peritoneal catheter that offers this unique subcutaneous tunnel design. This catheter has an external and intra-abdominal Silastic (Dow Corning, Midland, Mich) segment and a transcutaneous segment with a flange and cuff of expanded polytetrafluoroethylene (PTFE). This catheter was designed to decrease the incidence of tunnel infections, catheter cuff extrusions, and exit site infections. The clinical experience with 57 Gore-Tex catheters and 47 Tenckhoff catheters at Ohio State University from May 1980 through April 1983 is presented. In addition, the Gore-Tex catheters surgical insertion technique and postoperative care procedures are described. There was a significant decrease in the incidence of tunnel infections with the Gore-Tex catheter versus the Tenckhoff catheter (0.03 versus 0.21 infections per patient-year, respectively; P less than .05). There was no significant difference between the Gore-Tex catheter and the Tenckhoff catheter with regard to the patient peritonitis rate (1.12 versus 1.38 episodes of peritonitis per patient-year, respectively) or the exit site infection rate (0.65 versus 0.50 infections per patient-year, respectively). There were no cuff extrusions with the Gore-Tex catheter. The decrease in the incidence of tunnel infections with the Gore-Tex catheter suggests that the PTFE barrier inhibits longitudinal bacterial movement and avoids bacterial sequestration. Patients with repeat tunnel infections may benefit from a Gore-Tex catheter placement.

Adverse Effect of Exercise on Immune Complex-Mediated Glomerulonephritis

To assess the effect of strenuous daily exercise on immune complex-mediated glomerulonephritis (GN), rabbits were randomly assigned to one of three experimental groups: Group I (n = 12): treadmill exercise for 28 days plus twice weekly intravenous injections of saline. Group II (n = 10): treadmill exercise for 28 days plus twice weekly intravenous bovine serum albumin (BSA) injection. Group III (n = 9): intravenous doses of BSA, as in group II, but no exercise. Blood and urine samples were collected from each animal periodically during the 28-day experimental period. On the 29th day of the study all animals were sacrificed and tissue taken for renal histopathologic studies. We found that in group II (exercise + GN) abnormal albuminuria was more frequent (p less than 0.001), blood urea nitrogen (BUN) levels rose significantly with time (p less than 0.02) and hematuria (blood in renal tubules) was more common (p less than 0.05), compared to group III (GN only). The differences between groups II and III could not be explained by the effect of exercise alone since group I (exercise only) developed no abnormal albuminuria, BUN levels or hematuria during the course of the study. These findings suggest that strenuous exercise superimposed on active immune complex-mediated GN results in worsening of the abnormal glomerular function.

Analysis of a New Technique to Stabilize the Chronic Peritoneal Dialysis Catheter

A significant cause of morbidity for peritoneal dialysis patients is catheter dysfunction. In our experience, the most common cause of catheter dysfunction was cephalad migration of the catheter tip out of the true pelvis. A new technique for catheter placement that reduces catheter migration from 35% to 6% (P less than .01 chi 2) is described. Our results demonstrate that peritoneal catheters which dysfunction because of catheter flip generally do so in the first 3 months.

Effect of phosphate binders on supplemental iron absorption in healthy subjects.

A single‐dose, prospective, randomized, four‐treatment, four‐period crossover study was conducted to determine the acute effect of therapeutically equivalent doses of three commonly used phosphate binders on oral iron absorption. Twenty‐three healthy subjects received 65 mg of elemental iron alone and with each phosphate binder (calcium carbonate 3000 mg, calcium acetate 2668 mg, or sevelamer HCl 2821 mg). Area under the change in plasma iron concentration‐time curve over 6 hours postdosing was measured. ANOVA was used to assess the statistical significance of differences in iron absorption among the treatments. The relative bioavailability of iron administered with each phosphate binder compared to iron administered alone was estimated. The relative iron bioavailabilities (95% confidence intervals) for the calcium carbonate, calcium acetate, and sevelamer HCl treatments were 0.81 (0.70, 0.94), 0.73 (0.63, 0.85), and 0.90 (0.78, 1.05), respectively. Thus, single doses of both calcium‐based phosphate binders significantly reduced single‐dose iron absorption, while sevelamer HCl did not.

On the natural tendency to progressive loss of remaining kidney function in patients with impaired renal function.

Patients who lose more than 50% of their functioning renal mass are at risk to develop progressive deterioration of their remaining kidney function, even though the process that caused the original loss of kidney function may no longer be present. The glomerular capillary hyperperfusion, hypertension, and hyperfiltration that occur in the surviving nephrons may play an important role in the natural tendency for renal function to deteriorate. Nevertheless, recent studies suggest that these glomerular hemodynamic events may not be the final common pathway for the natural deterioration of renal function, as was once thought. With regard to the general management of patients with impaired renal function, recent evidence suggests that controlling systemic blood pressure, reducing dietary protein and phosphorus intake, and controlling hyperlipidemia may be effective in slowing the loss of renal function.

Reversal of End-Stage Kidney Failure in Two Scleroderma Patients Treated With Anticoagulation

Two patients with progressive systemic sclerosis (scleroderma) developed renal failure which required thrice weekly hemodialysis. While receiving hemodialysis treatments and warfarin, their renal function improved and it was possible to discontinue hemodialysis after 9 mo in Case 1 and after 3 mo in Case 2. The recovery of renal function in these patients suggests therapy with warfarin may play a role in the treatment of scleroderma renal failure.

Glomerular Basement Membrane Splitting and Microaneurysm Formation Associated with Nitrosourea Therapy

A patient who developed renal insufficiency following nitrosourea therapy is reported. Light, immunohistochemical, and electron microscopic studies of the renal biopsy disclosed an unusual glomerular basement membrane injury. Light microscopy showed extensive basement membrane splitting and capillary aneurysm formation. Electron microscopic examination revealed an extensive subendothelial accumulation of electron-lucent granular material. The glomerular basement membrane was separated from the mesangium and showed splitting of the lamina densa. Immunofluorescent and immunoperoxidase staining of the glomeruli was negative for immunoglobulin, complement, and fibrinogen. This form of nitrosourea-associated glomerular injury has not been described previously.

Light-chain proteinuria: Spurious false-negative reaction to sulfosalicylic acid

Excerpt To the editor: We report the case of a patient with multiple myeloma and renal failure secondary to heavy urinary excretion of kappa light chains. This diagnosis was missed initially becaus...