Controlled trial of enalapril in patients with chronic fluid overload undergoing dialysis

About one third of patients receiving dialysis for end stage renal failure have chronic fluid overload despite advice to restrict their oral fluid intake. To investigate the potential of an angiotensin converting enzyme inhibitor in reducing the urge to drink and consequent gain in weight, a double blind, placebo controlled crossover trial of enalapril was conducted in 25 patients receiving dialysis who had fluid overload. The trial comprised a baseline period of four weeks; two periods of treatment, each of four weeks, during which patients received either placebo or enalapril 5 mg twice each week; and a follow up period of four weeks. Five patients withdrew from the trial, one because of an adverse drug reaction to enalapril. A range of biochemical and behavioural variables was measured during the baseline period, at the completion of periods 1 and 2, and during follow up. These variables included gain in weight between dialysis sessions; blood pressure; plasma concentrations of sodium, angiotensin II, and vasopressin; plasma renin and angiotensin converting enzyme activities; osmolality; and estimations of thirst, intake of fluid, and control of drinking. Enalapril caused a significant reduction in gain in weight between dialysis sessions, thirst, and oral intake of fluid in parallel with significantly increased renin activity, significantly decreased angiotensin converting enzyme activity, and decreased concentrations of angiotensin II. Gain in weight and angiotensin converting enzyme activity returned to baseline values once patients stopped taking enalapril.These results suggest that enalapril may act on the renin-angiotensin system and reduce intake of fluid by inhibiting angiotensin converting enzyme.     

Acute haemolysis due to concentrated dialysis fluid.

Fatal acute haemolysis occurred in a 65-year-old man undergoing regular home haemodialysis for terminal renal failure. Circumstantial evidence indicating that the haemolysis resulted from exposure to concentrated dialysis solution was supported by in-vitro studies. Frank haemolysis in blood samples occurred at a dilution of greater than or equal to 1/2 of dialysis fluid. Osmotic fragility tests of surviving red blood cells showed 47% haemolysis at a dilution of 1/2 and greater than 90% haemolysis at a dilution of 1/1. Urgent design modifications to the proportionating machine are being undertaken to prevent such an accident recurring.     

Continuous ambulatory peritoneal dialysis: one year's experience in a UK dialysis unit.

Thirty-two patients aged 8-63 years trained to manage themselves by continuous ambulatory peritoneal dialysis for end-stage renal failure achieved better steady-state serum biochemistry and much higher haemoglobin and lower serum phosphate concentrations than during treatment with haemodialysis up to one year before. Two patients, however, returned to intermittent haemodialysis because of recurrent peritonitis. Costs of the technique during the first year were less than half those incurred in the first year of home haemodialysis. Nevertheless, the major advantage was the ease with which patient independence and rehabilitation could be achieved. This technique is an appreciable advance over other forms of management for end-stage renal failure. Nevertheless, until it is more refined and long-term problems have been assessed it should probably be used only in established renal units where back-up treatments are available.     

Contamination of peritoneal dialysis fluid by filamentous fungi

Peritonitis is a frequent complication in peritoneal dialysis. It may be caused by contamination of the dialysis tubing or by extension of the catheter exit site. Gram-positive bacteria are the most common organism, accounting for 60% of all documented cases of continuous ambulatorial peritonitis dialysis. Fungi are isolated from to 1-15% of cases. Forty-nine out of 490 bottles containing fluid for peritoneal dialysis were randomly selected for microbiological analysis in S?o Paulo, Brazil. In this report the contamination of peritoneal dialysis fluid by Chaetomium globosum and Chrysonilia sitophila is reported.     

Treatment of renal osteodystrophy with 1,25-dihydroxycholecalciferol.

Nine patients with renal osteodystrophy were tested for 6.5 to 35 months with 1,25-dihydroxycholecalciferol (1,25-DHCC). A close biochemical follow-up was performed during the first 6 months of treatment, including biweekly determinations of serum calcium, phosphorus, magnesium, alkaline phosphatase and creatinine levels. A bone biopsy, radiologic investigations and determinations of plasma levels of immunoreactive parathyroid hormone (IPTH) and intestinal absorption of calcium 47 were performed before and after the 6 months. Although the five patients with osteitis fibrosa showed a significant improvement, the four with predominantly osteomalacic lesions showed no response to treatment. These four had a normal initial plasma iPTH level, higher serum calcium levels than the other five patients, extreme sensitivity to 1,25-DHCC, with frequent episodes of hypercalcemia, and only a slightly increased serum alkaline phosphatase level, which remained unchanged during treatment. All but one of the patients, irrespective of the histologic abnormality, showed a decrease in the uptake of radionuclide by bone after treatment. The renal function of one patient, a man with long-standing stable renal failure who had not undergone dialysis, deteriorated during treatment.     

Lavage fluid from continuous ambulatory peritoneal dialysis. A model for mesothelial cell changes

Continuous ambulatory peritoneal dialysis (CAPD) lavage can be interpreted as an artificial short-term ascites. The cellular content of 362 CAPD specimens from 32 patients was investigated. Irregular inflammatory reactions were seen in 85.3% of the specimens and eosinophilia in 27.6%. Mesothelial aggregates of great variability were registered in 59.4% of the specimens and mainly atypical mitoses in 7.5%. The cytologic changes seen in those patients from whom lavage fluids were examined over 10 to 12 months did not correlate with the changes in blood chemistry (BUN and creatinine) in those cases.     

Cytology of peritoneal fluid from patients on continuous ambulatory peritoneal dialysis

Peritoneal fluids from 41 patients on continuous ambulatory peritoneal dialysis (CAPD) were examined. The patients were divided into a short-term group (18 patients with CAPD up to one year) and a long-term group (23 patients with CAPD for one to seven years). Peritoneal fluids from a control group, consisting of ten nondialysis patients with ascites, were also examined. The cellular background of the peritoneal fluids and, in particular, the morphology of the mesothelial cells were studied. The following were found to be significantly increased in the CAPD groups: background lymphocytes, mesothelial exfoliation in three-dimensional clusters, mesothelial nuclear size and the number of mesothelial nucleoli. All of these features increased slightly with an increased duration of the dialysis. These findings emphasize that peritoneal dialysis of any duration can induce significantly atypical changes in mesothelial cells.     

Effect of I,25-dihydroxycholecalciferol in renal osteodystrophy.

A 23-year-old man with medullary cystic disease had been undergoing hemodialysis for 5 years and had become confined to a wheelchair because of renal osteodystrophy. He was treated with 125-dihydroxycholecalciferol, 2.0 mug (later 1.0 mug) three times a week, administered by way of the venous end of the dialysis machine. Within 1 month bone pain lessened and his ability to stand and walk improved. By 3 months he was walking short distances and by 5 months, long distances. Calcium balance was near zero before treatment and was strongly positive during treatment. Bone mineral content in the lower femur, measured by photon absorptiometry, increased at a rate of 32.2% per year. In contrast, 26 other patients on long-term hemodialysis had a mean loss of bone mineral content of 14.0% per year. Radiographs taken during treatment showed a decrease in subperiosteal bone resorption and healing of a pseudofracture. A significant decrease in the mean serum alkaline phosphatase value was noted during treatment, but no significant changes in mean serum calcium or phosphorus values were seen.     

Improving medication compliance: a randomised clinical trial.

A medical monitor which recorded the date and hour each time a medicine bottle was opened was used to evaluate a programme for improving patients'' compliance with their treatment. Eighty-two patients with glaucoma who had been prescribed pilocarpine eye drops three times daily to prevent visual loss were randomised into two groups. Both groups used the medication monitor during two 20-day periods, but before the second period the experimental group were given an education and tailoring programme in an attempt to improve their compliance. Nine patients missed the second treatment period and were excluded from the analysis. The patients in the experimental group showed significantly improved compliance when compared with the control group. The numbers of missed doses were reduced by about half, as was the proportion of time that exceeded the eight-hour dose intervals. Follow-up studies are needed to determine how long the improved compliance persists, but anyone considering setting up an education and tailoring programme should recognise the extent to which therapeutic efforts are wasted because of non-compliance.