Methods of controlling hyperphosphatemia in patients with chronic renal failure.

The problem of hyperphosphatemia in patients with chronic renal failure is reviewed. The importance of high plasma phosphorus levels in the pathogenesis of hyperparathyroidism is concisely discussed. Basic concepts about phosphorus metabolism in normal persons and in patients with chronic renal failure are outlined. This is followed by a detailed discussion of the various therapeutic methods to control hyperphosphatemia. Dietary restriction, dialysance of phosphorus, and the use of the currently available phosphorus binders are comprehensively discussed. Finally, the various clinical situations associated with failure to control hyperphosphatemia are reviewed.

Current advances in the therapy of secondary hyperparathyroidism and osteitis fibrosa.

Secondary hyperparathyroidism is commonly observed in dialysic patients. Recent observations demonstrate a direct inhibitory effect of calcitriol on parathyroid hormone (PTH) synthesis and secretion. These observations may have important clinical and therapeutical implications. Thus, several studies have shown that intravenous calcitriol, in dialysis patients with severe secondary hyperparathyroidism, has a direct inhibitory effect on PTH levels. Furthermore, the sigmoidal PTH-calcium relationship is shifted toward a more normal range after intravenous calcitriol. In addition, the use of calcitriol early during the course of renal failure prior to dialysis has demonstrated therapeutic benefits. Thus, both early therapy with oral calcitriol and later during maintenance dialysis, the addition of the intravenous form may provide various therapeutical alternatives which make surgical parathyroidectomy rarely necessary. Furthermore, the course of patients undergoing surgical parathyroidectomy is not benign.

Peritoneal dialysis in renal failure associated with spinal cord injury.

Nine patients with chronic renal failure associated with long-standing spinal cord injury were treated with peritoneal dialysis for periods ranging from 3 days to 12 months. Indwelling peritoneal catheters and automated peritoneal dialysis machines were used in the majority of cases. The procedure was generally used as an interim measure while awaiting placement or maturation of the blood access for hemodialysis. Several patients, however, underwent peritoneal dialysis for prolonged periods, including a patient who was on home-peritoneal dialysis for 12 months. The main complications resulting from 653 patient-day treatments consisted of six bouts of peritonitis and a single case of bowel perforation. Azotemia, fluid electrolytes and acid-base status were satisfactorily controlled with peritoneal dialysis. The results were comparable with those obtained during hemodialysis. Peritoneal dialysis, therefore, appears to be a reasonable alternative to hemodialysis in the management of chronic renal failure in spinal cord injured patients.

Lipid abnormalities in chronic renal failure associated with spinal cord injury.

Serum lipid fractions were studied in ten patients with chronic renal failure (CRF) associated with long-standing spinal cord injury (SCI). A group of age-and-sex-matched patients with long-standing SCI but normal renal function were included for comparison. Serum triglycerides were markedly elevated in SCI-CRF patients. Both SCI groups exhibited moderate hypocholesterolemia. High density lipoprotein (HDL) cholesterol was severely reduced in the SCI-CRF group and moderately reduced in the SCI-control group. Chronic renal failure, reduced physical activity and several other factors may be operative in the genesis of hypertriglyceridemia and reduced HDL-cholesterol levels in this condition. Further investigations are necessary to examine the possible effect of these lipid abnormalities on the cardiovascular system in these patients.

Survival on maintenance dialysis in patients with chronic renal failure associated with paraplegia and quadriplegia.

Forty men with end-stage renal failure associated with spinal cord injury were treated with maintenance hemodialysis. There were 28 paraplegic and 12 quadriplegic patients. Survival on dialysis was significantly shorter in quadriplegics (5.5 +/- 5.0 months) than paraplegics (22.9 +/- 27.0 months). The cumulative I- and 2-year survival in paraplegics were 60 per cent and 52 per cent respectively. The respective values for quadriplegics were 34 per cent and 17 per cent. Various infections proved to be the immediate cause of death in the majority of our patients.

Hematologic features of chronic renal failure associated with spinal cord injury.

We examined the available hematologic data on 43 spinal cord injury (SCI) patients with end-stage renal disease (ESRD) treated with hemodialysis since 1972. A control group consisting of 45 ESRD patients without SCI was included for comparison. Moderate to severe anemia was found in all patients. The observed anemia was generally normocytic, normochromic, and associated with a low reticulocyte response. Transfusion requirement in the SCI group was considerably more than in the control group. There was a high incidence of splenomegaly, splenic amyloidosis, and lymph node enlargement in the SCI group. Lymph node and bone marrow amyloid deposits were found in some SCI patients but not in the control subjects.

Urolithiasis in patients with spinal cord injury.

The composition of the stone was determined in 24 paraplegic patients from whom 26 stones were surgically removed. Twenty-five of the 26 stones consisted of 90 per cent magnesium ammonium phosphate and 10 per cent carbonate apatite. The remaining single stone was composed of 90 per cent calcium oxalate and 10 per cent magnesium ammonium phosphate. Renal function improved significantly with the removal of the stones.