D. O. Oliver

Outcome in patients on continuous ambulatory peritoneal dialysis and haemodialysis: 4-year analysis of a prospective multicentre study

In a study in seven large renal units in England, the morbidity and mortality of all patients starting continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis during 1983-85 were monitored prospectively over a 4-year period and related to reasons for choice of therapy and potential risk factors. 610 new patients (median age 52 years, range 3-80 years) started CAPD; 16% had diabetes mellitus and 21% cerebrovascular or cardiovascular disease. 329 patients (median age 48 years, range 5-77 years) started haemodialysis; 7% had diabetes mellitus and 17% cerebrovascular or cardiovascular disease. The Kaplan-Meier patient survival estimates at 4 years were 74% for haemodialysis and 62% for CAPD; technique survival figures for the same period were 91% for haemodialysis and 61% for CAPD. Coxs proportional hazards regression analysis showed that cerebrovascular/cardiovascular disease, age over 60 years, and diabetes mellitus were important predictors for survival in CAPD patients; there were no risk factors associated with permanent change to haemodialysis. In the haemodialysis group early change to CAPD was associated with presence of cerebrovascular or cardiovascular disease. The major cause of drop-out in both groups was transplantation. The mean length of hospital admission was 14.8 days per patient-year for CAPD and 12.4 days per patient-year for haemodialysis.

Effects of 1,25-dihydroxycholecalciferol on calcium absorption, muscle weakness, and bone disease in chronic renal failure.

Abstract Small amounts (0.35-2.7 μg.) of 1,25 dihydroxycholecalciferol (1,25-D.H.C.C.), the hormonally active metabolite of vitamin D 3 , were given to eleven patients with chronic renal failure for 4-150 days. 1,25-D.H.C.C. given for 4-8 days increased intestinal 47 Ca absorption without causing large changes in plasma calcium or phosphate, or in plasma or urine hydroxyproline measurements. 1,25-D.H.C.C. was given for a longer period (58 and 150 days) to two of the patients. In one, a 14-year-old girl, plasma alkaline phosphatase and non-protein bound hydroxyproline fell and there was healing of radiological rickets and secondary hyperparathyroidism; and in the other, a man of 58 years, there was striking improvement in muscle weakness. The resistance to treatment with vitamin D in chronic renal failure is probably related to impaired metabolic conversation to active derivatives, the most important of which may be 1,25–D.H.C.C. 1,25–D.H.C.C. seems capable of correcting some, if not all, of the disturbances in calcium metabolism in this disorder.

Imaging of haemodialysis-associated amyloidosis with 123I-serum amyloid P component.

Long-term haemodialysis is frequently complicated by amyloid deposition in which the fibrils consist of beta 2-microglobulin. Dialysis-related amyloid disease causes extensive morbidity and has been associated with deaths in some cases. All amyloid deposits contain amyloid P component that is derived from the normal circulating protein, serum amyloid P component (SAP). We have used scintigraphic imaging after injection of 123I-labelled SAP to assess the distribution of amyloidosis in 38 patients receiving long-term haemodialysis for end-stage renal failure. There was focal localisation of tracer at all sites where histological examination confirmed amyloid deposition. Splenic uptake was seen in 12 patients, indicating splenic amyloidosis, but there was no evidence of other visceral involvement. 6 control subjects who had been dialysed for under 1.5 years showed no localisation of tracer, nor was there any uptake of 123I-labelled human serum albumin in 3 long-term dialysis patients with histologically confirmed amyloidosis and positive 123I-SAP images. Negative scans were also obtained in 5 patients who had been transplanted 0.8-2.4 years previously, despite past evidence of dialysis arthropathy (5) and histologically proven amyloidosis (4). 123I-SAP scintigraphy may be helpful as a non-invasive method for both the diagnosis and monitoring of dialysis-associated amyloidosis.

EVIDENCE THAT ENDOGENOUS CALCITONIN PROTECTS AGAINST RENAL BONE DISEASE

Plasma concentrations of calcium, phosphate, alkaline phosphatase (A.P.), immunoreactive calcitonin (iC.T.), and immunoreactive parathyroid hormone (iP.T.H.) were measured in fifty-two patients with chronic renal failure on maintenance haemodialysis. On the basis of a bimodal distribution of values for plasma-A.P. the patients were dividied into 2 groups. In those patients with normal A.P. concentratons as well as in twenty-eight normal subjects there was a positive correlation between iP.T.H. and iC.T. which was independent of plasma calcium or phosphate. Patients with increased plasma-A.P. had higher concentrations of iP.T.H., lower concentrations of iC.T., and showed a negative relation between the concentrations of the two hormones. It is suggested that a possible factor in the pathogenesis of renal bone disease is a failure to secrete C.T. in adequate amounts.

Subcutaneous administration of recombinant human erythropoietin to subjects on continuous ambulatory peritoneal dialysis: an erythrokinetic assessment

Erythrokinetic studies were performed in subjects on continuous ambulatory peritoneal dialysis, during a trial examining the effectiveness of subcutaneous administration of recombinant human erythropoietin (r‐HuEPO) in correcting the anaemia associated with end stage renal disease. 15 subjects (mean haemoglobin concentration 6.9 g/dl, SD 1.1) entered the study, and during treatment 9 were restudied at a haemoglobin concentration of 11–11.5 g/dl and six under‐went a third study at haemoglobin 13–13.5 g/dl. By adjusting the dose of r‐HuEPO, a stepwise increase in haemoglobin concentration was achieved, and this was accompanied by increases in total red cell volume and erythron transferrin uptake. Plasma volume decreased as red cell volume increased, leaving total blood volume essentially unchanged. Red cell survival, modestly reduced before treatment (mean 64, range 44–96 d, n= 6) tended to increase during treatment and when subjects were retested at a haemoglobin concentration of 13–13.5 g/dl (after 38–62 weeks treatment), the mean increase in red cell survival was 20 d (95% confidence interval 1–39 d).