Anterior pituitary dysfunction in patients with chronic renal failure treated by hemodialysis or continuous ambulatory peritoneal dialysis

Cortisol, prolactin, and growth hormone responses to insulin-induced hypoglycemia were measured in 20 patients undergoing continuous ambulatory peritoneal dialysis or intermittent hemodialysis. The plasma cortisol responses were normal; however, the increments in serum prolactin and growth hormone concentrations were impaired in most patients. The growth hormone responses were lower (p less than 0.05) in those patients treated by continuous ambulatory peritoneal dialysis, but there were no other significant differences between the two patient groups. These results show that anterior pituitary dysfunction persists in some patients with chronic renal failure despite maintenance dialysis therapy.     

Hyperprolactinemia in patients with renal insufficiency and chronic renal failure requiring hemodialysis or chronic ambulatory peritoneal dialysis

Hyperprolactinemia is common in patients with renal failure. Because radiographic contrast material given during a computed tomographic (CT) scan of the sella as part of the evaluation for prolactinoma worsens renal insufficiency, we attempted to define the point at which hyperprolactinemia becomes an expected finding in patients with renal insufficiency in this study. Of 59 patients with serum creatinine levels of 1.5 to 12 mg/dL, 16 (27.1%) were hyperprolactinemic. Of these 16, nine were not taking medications known to raise prolactin levels and their prolactin levels were less than 100 ng/mL. In the eight patients taking medications prolactin levels were much higher. In one patient the prolactin level fell from 2,210 to 100 ng/mL when methyldopa was discontinued. In patients with chronic renal failure prolactin levels were similar regardless of the method of dialysis. We conclude that in the absence of medications known to affect prolactin secretion, hyperprolactinemia occurs infrequently (18.3%) and, when it occurs, is mild (less than 100 ng/mL). Marked hyperprolactinemia may occur in patients taking such medications. These should be stopped and the prolactin level rechecked before a CT scan is performed.     

Gastric emptying in patients with chronic renal failure on continuous ambulatory peritoneal dialysis

Radionuclide gastric emptying studies were carried out on 20patients with end-stage renal failure (ESRF) undergoing continuousambulatory peritoneal dialysis (CAPD). Nine of the patientshad diabetes mellitus. Eight normal volunteers were also studiedto establish normal ranges. Solid and liquid emptying patternswere investigated simultaneously using a meal made up of a solidphase labelled with ^99mTechnetium and a liquid phase labelledwith ¹¹¹Indium. The solid emptying fitted a model with a lagphase followed by a linear emptying phase and the liquid emptyingfitted a single exponential. Nine of the 20 patients (four diabetic,five non-diabetic) were found to have delayed solid emptying,and four of these (two diabetic, two non-diabetic) also haddelayed liquid emptying. No correlation was found between anyof the parameters studied and the clinical symptoms of the patients.It is concluded that almost half of the patients studied hadabnormal gastric emptying, but that many of these did not sufferfrom severe symptoms.     

Plasma interleukin-6 levels in continuous ambulatory peritoneal dialysis and hemodialysis patients.

Plasma levels of interleukin-6 (IL-6), a cytokine known to be involved in lymphocyte activation and in inflammation, were studied in 10 normal volunteers, 21 continuous ambulatory peritoneal dialysis (CAPD) patients and 41 hemodialysis patients. Plasma IL-6 levels in hemodialysis patients were significantly higher than those in normal volunteers and CAPD patients (p less than 0.05). The means of plasma IL-6 concentrations before and after hemodialysis did not change significantly. While IL-6 in peritoneal dialysate was detectable in only 3 of the 21 CAPD patients without peritonitis, it was extremely high in 2 patients with bacterial peritonitis. IL-6 levels decreased as peritonitis subsided.     

Evoked potentials in children with chronic renal failure,treated conservatively or by continuous ambulatory peritoneal dialysis

Children with chronic renal failure (CRF) show developmental, intellectual and motor disturbances. It is questionable if an early start of renal replacement therapy may prevent or delay these disturbances. We studied the neurological and intellectual development of children <5 years suffering from CRF (creatinine clearance <20% of normal) prospectively, over a period of 3 years. As part of the neurological study, brainstem auditory evoked potentials (BAEP) and somatosensory evoked potentials (SSEP) were recorded. Measurements were performed in a group of 22 children every 6 months. In 18 of these children CRF was present from birth. Sufficient data were available for analysis in 19 (BAEP) and 22 (SSEP), respectively. A delay of peak I of BAEP gave indications for peripheral conduction disturbances, possibly due to cochlear dysfunction. Brainstem conduction was normal. There were no differences between the children treated conservatively (n = 9) and those treated with continuous ambulatory peritoneal dialysis (CAPD) (n = 10). In children <2.5 years SSEP showed a delayed thalamocortical conduction, which was not observed in older children. This might indicate a delayed myelination in young children with CRF. No differences were found between the children treated conservatively (n = 10) and those treated with CAPD (n = 12).     

Protein losses in patients receiving continuous ambulatory peritoneal dialysis

Total protein and 12 specific proteins were measured in dialysates from 8 patients on continuous ambulatory peritoneal dialysis during training. Mean daily loss of total protein was 10.5 g and this included 5.2 g albumin, 805 mg of the immunoglobulins G, A and M, 323 mg transferrin and 530 mg of the remaining 7 proteins measured. The plasma to dialysate ratio of protein concentrations correlated with the natural logarithm of molecular weight, suggesting that proteins in dialysate are an ultrafiltrate of plasma. A greater loss of proteins overnight was due to longer dwell time as the mean rate of loss was similar for all exchanges. Losses were similar with 1.36% and 3.86% dextrose fluids, suggesting that the initial effects of hypertonicity are diminished or reversed by dilution and absorption of dextrose. Daily outflow volumes for 4 patients correlated inversely with the quantities of several proteins removed, probably due to effects of osmolality. It is concluded that protein losses are related to plasma concentration, molecular weight and osmolality of the dialysis solution and to the physiology of the patient.     

Alleviation of sleep apnea in patients with chronic renal failure by nocturnal cycler-assisted peritoneal dialysis compared with conventional continuous ambulatory peritoneal dialysis

Nocturnal hemodialysis has been shown to improve sleep apnea in patients who receive conventional hemodialysis. It was hypothesized that nocturnal peritoneal dialysis (NPD) also is effective in correcting sleep apnea in patients who receive continuous ambulatory PD (CAPD). Overnight polysomnography (PSG) was performed in 46 stable NPD and CAPD patients who were matched for demographic and clinical attributes. The prevalence of sleep apnea, defined as an apnea-hypopnea index (AHI; or frequency of apnea and hypopnea per hour of sleep) > or =15, was 52% for NPD patients and 91% for CAPD patients (P = 0.007). The mean (+/-SD) AHI in NPD and CAPD patients was 31.6 +/- 25.6 and 50.9 +/- 26.4 (P = 0.025), respectively. For validation of the efficacy of NPD in alleviating sleep apnea, a fixed sequence intervention study was performed in which 24 incident PD patients underwent one PSG study during mandatory cycler-assisted NPD while awaiting their turn for CAPD training and a second PSG recording shortly after they were established on stable CAPD. The prevalence of sleep apnea was 4.2% during NPD and 33.3% during CAPD (P = 0.016). AHI increased from 3.4 +/- 1.34 during NPD to 14.0 +/- 3.46 during CAPD (P < 0.001). With the use of bioelectrical impedance analysis, total body water content was significantly lower during stable NPD than CAPD (32.8 +/- 7.37 versus 35.1 +/- 7.35 L; P = 0.004). NPD delivered greater reductions in total body water (-2.81 +/- 0.45 versus -1.34 +/- 0.3 L; P = 0.015) and hydration fraction (-3.63 +/- 0.64 versus -0.71 +/- 0.52%; P = 0.005) during sleep. Pulmonary function tests remained unchanged before and after conversion from NPD to CAPD. These findings suggest that NPD may have a therapeutic edge over CAPD in sleep apnea that is associated with renal failure as a result of better fluid clearance during sleep.     

The red blood cell deformability in patients suffering from end stage renal failure on hemodialysis or continuous ambulatory peritoneal dialysis

Anemia is the main problem for patients suffering from end stage renal disease (ESRD). This study aimed to determine whether the index of rigidity (IR), that shows red blood cells (RBCs) deformability and the possible IR disturbances can provide an explanation about the cause of anemia, in patients undergoing maintenance hemodialysis (HD) or on peritoneal dialysis. The IR was determined in 39 hemodialyzed patients, who were already in dialysis for a period of time ranging from 16 to 120 months (mean+/-SD=41.8 +/-24.1) (Group A). Furthermore, the IR was measured in 32 patients on continuous ambulatory peritoneal dialysis (CAPD), who were in CAPD for a period of time ranging from 6 to 60 months (mean+/-SD = 10.7+/-9.9) (Group B). Finally, the IR was determined in 17 normal individuals (group C). The RBCs IR was measured twice in group A (before and after the end of a hemodialysis session) and once in groups B and C. The IR was determined by hemorrheometry (method of filtration), using special equipment. In group A the IR was increased in comparison to the control group (C) (17.9+/-6.2 vs. 10.2+/-1.8, p<0.0001). This increase was even higher in the measurement at the end of the hemodialysis session (paired t-test, p < 0.0001). The RBCs IR in CAPD patients was significantly lower than that of HD patients (12+/-3.8 vs. 17.9+/-6.2, p<0.0001) and was not statistically different from the control group (12+/-3.8 vs. 10.2+/-1.8, p=0.068). It is concluded from the study that: 1) in HD patients occur disturbances in the deformability of the RBCs, that are worsened by the hemodialysis session; 2) the index of rigidity of RBCs is significantly higher in the HD patients than in CAPD patients; 3) in patients on CAPD, the disturbance of deformability of the RBCs was less in comparison to the control group, which however does not reach the statistically significant levels.     

Oxalate elimination via hemodialysis or peritoneal dialysis in children with chronic renal failure

. Oxalate elimination and oxalate dialysance via hemodialysis (HD) or peritoneal dialysis (CAPD) has not been studied in detail in pediatric patients. We studied plasma oxalate, oxalate elimination, and oxalate dialysance in 15 infants and children undergoing CAPD (9 female, 6 male, aged 9 months to 18 years) and in 10 children on HD (4 female, 6 male, aged 7 – 18 years). Two children in each group had primary hyperoxaluria (PH). The mean duration of dialysis prior to examination was 12±11 months in CAPD and 31±23 months in HD patients. Bicarbonate HD was performed 5 h three times a week, CAPD consisted of five daily exchanges in 5 patients and four changes in the remaining 10 children (dwell volume 40 ml/kg body weight, 2.3 g/l glucose). Although oxalate dialysance was significantly higher in HD (mean 115.6 ml/min per 1.73 m² in HD versus 7.14 ml/min in CAPD), mean oxalate elimination per week was not different between both renal replacement therapies (3,478 μmol/1.73 m² surface area/week in CAPD versus 3,915 μmol/1.73 m² per week in HD). Oxalate elimination in patients with PH was between 6,650 and 9,900 μmol/week. Plasma oxalate remained elevated in both procedures [28 – 84 μmol/l in CAPD (92/148 in PH) and 33 – 101 μmol/l in HD (70/93 in PH)]. Oxalate elimination can be increased by a more frequent hemodialysis regimen. Received May 24, 1995; received in revised form and accepted October 31, 1995     

Plasma concentration and peritoneal clearance of oxalate in patients on continuous ambulatory peritoneal dialysis (CAPD)

Accumulation of oxalate, resulting in high plasma levels, is a common finding in end-stage renal disease. We investigated plasma concentration and peritoneal clearance of oxalate in 14 patients on continuous ambulatory peritoneal dialysis. The plasma oxalate levels in these patients (30.2 +/- 11.2 mumol/l) were as high as those in hemodialysis patients before dialysis (31.9 +/- 11.1 mumol/l). There was a significant correlation between plasma oxalate and urea nitrogen appearance (UNA). Dietary protein seems to be an important oxalate source in these patients, because the UNA reflects protein intake in stable patients. The mean peritoneal oxalate clearance was 6.64 +/- 1.56 l/day, close to the creatinine clearance. These results suggest that the plasma oxalate levels in CAPD patients may be sufficiently high to induce calcium oxalate deposition, and that methods of increasing oxalate removal and reducing oxalate burden are necessary for CAPD patients.     

Peritoneal tuberculosis in patients receiving continuous ambulatory peritoneal dialysis.

BACKGROUND: Patients with chronic renal failure have an increased risk of tuberculosis (TB). This occurs with much higher frequency within the first 12 months of initiating dialysis and is usually extrapulmonary in nature. Patients most at risk are those from susceptible ethnic groups, especially the Indian subcontinent. Peritoneal TB, otherwise relatively uncommon, has emerged as an important form of TB in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). METHODS: All cases of peritoneal TB occurring at our institution in patients undergoing CAPD over a 13 year period were identified and analysed. RESULTS: Eight cases were identified, of which seven were non-Caucasian. These patients' characteristics and outcomes are presented. All were undergoing CAPD and most developed TB within 12 months of initiating dialysis. All presented with fever, but symptoms and signs were indistinguishable from bacterial peritonitis. Six were culture-positive, mainly from peritoneal dialysis fluid, but only two cases proved smear-positive. All were treated with standard anti-tuberculous chemotherapy. Three went on to permanent haemodialysis as a result of peritonitis and three have died, one of these as a result of TB. CONCLUSIONS: Peritoneal TB, whilst otherwise relatively uncommon, is an important manifestation of TB in CAPD patients and usually develops soon after commencing dialysis. The reasons for this are unknown and require further research.     

Calcium oxalate kidney stones in patients on continuous ambulatory peritoneal dialysis

Kidney stones were passed by ten out of 186 patients with endstage renal disease who were treated with continuous ambulatory peritoneal dialysis (CAPD). Stones from seven patients were examined by x-ray diffraction. In five of them the stones were composed of calcium oxalate monohydrate. The urine calcium oxalate activity product was determined in 44 CAPD patients, eight of whom were stone formers, and compared to that of 120 normal volunteers. In CAPD patients, mean urine ionic-calcium concentration was lower than in normal subjects whereas mean urine ionic-oxalate concentration was significantly higher than in normal subjects. In normal urine samples, the calcium oxalate activity product showed a significant correlation with both the urine ionic-calcium and the ionic-oxalate concentrations. In contrast, in CAPD patients the calcium oxalate activity product correlated with the ionic-calcium concentration but not with ionic-oxalate. Although the urine ionic-calcium concentration is lower in CAPD patients than in normal subjects, it is the relative increase in its concentration which appears to be associated with the increased risk of kidney stone formation in these patients. This relative hypercalciuria seems to follow 1,25(OH)2 vitamin D3 administration.     

Lipoprotein abnormalities in hemodialysis and continuous ambulatory peritoneal dialysis patients

Lipid abnormalities are important variables in the development of vascular atherosclerotic lesions in ESRD patients while Lp(a) represents an independent risk factor. In order to evaluate lipid changes in HD and CAPD patients, serum cholesterol (TC), HDLc, LDLc, TG, apolipoproteins (AI,AII,B,E), Lp(a), and albumin levels were estimated in 109 ESRD dialyzed patients, 46 in HD and 63 in CAPD (mean duration 50 +/- 40 and 25 +/- 19 months, respectively), and 45 volunteers with high serum levels of C and TG, without renal insufficiency. Both HD and PD group revealed statistically significantly higher levels than controls for TC, TG, LDL-C, Apo-B,-E, while HDL-C levels were significantly lower. Except for the lower serum albumin levels in both dialyzed groups after six months lower ApoAI levels and higher ApoB levels were observed in HD and PD patients respectively. Lp(a) levels remained unchanged in HD group, while a statistically significant increase appeared in PD patients that was negative correlated with the decreased serum albumin levels. These results indicate that renal replacement modalities result in a different effect in lipoprotein metabolism that may play an important role in atherosclerotic vascular disease of dialyzed ESRD patients.     

Behavior of beta 2-microglobulin in patients with chronic renal failure undergoing hemodialysis, hemodiafiltration and continuous ambulatory peritoneal dialysis (CAPD)

beta 2-microglobulin (beta 2-m) is the major component of a new form of amyloid deposit found in carpal tunnel syndrome and dialysis arthropathy of long-term hemodialysis patients. In 52 patients on maintenance hemodialysis, serum beta 2-m concentration was elevated to 37.9 +/- 1.4 (normal 1.2 +/- 0.6) mg/l. It was correlated with the time on hemodialysis (r = 0.43, p less than 0.01) and was inversely correlated with residual renal function (r = 0.87, p less than 0.001). In 20 patients on CAPD, beta 2-m likewise was increased to 31.6 +/- 2.3 mg/l; daily elimination by dialysate was only 34 mg (normal 150 mg). Hemodialysis with a cuprophane membrane caused a rise in serum beta 2-m, whereas hemodiafiltration with a polysulfone membrane performed in 5 patients over 2 1/2 months was accompanied by a decrease in serum beta 2-m from 39.5 +/- 0.7 to 29.7 +/- 1.0 mg/l predialysis (19.1 +/- 1.1 postdialysis). On the other hand, beta 2-m elimination reached only approximately 100 mg per day in spite of markedly elevated serum levels. It is concluded that serum beta 2-m is massively elevated in long-term hemodialysis and CAPD patients; contrary to routine hemodialysis with cuprophane membranes, newer more permeable membranes will permit some elimination of beta 2-m. However, based on quantitative considerations it seems difficult to obtain beta 2-m concentrations in the high normal or moderately elevated range with present day techniques.     

Plasma concentrations of 18-hydroxycorticosterone and aldosterone in continuous ambulatory peritoneal dialysis and hemodialysis patients

This study explores the hypothesis that the continuous ultrafiltration that accompanies continuous ambulatory peritoneal dialysis (CAPD) produces greater activation of the renin-angiotensin aldosterone axis than does the intermittent ultrafiltration that accompanies thrice weekly hemodialysis (HD). Plasma renin activity (PRA), active renin (AR), total renin (TR), inactive renin (IR), 18-hydroxycorticosterone (18-OH-B), aldosterone (PAC), and cortisol were measured in plasma from CAPD (n = 6) and HD (n = 10) patients. Blood from CAPD patients was sampled at 8 AM after overnight recumbency and at 12 noon after four hours ambulation. Blood from HD patients was sampled immediately pre-HD (8 AM) and post-HD (12 noon) at both 8 AM and 12 noon. PRA (P less than 0.01), AR (P less than 0.01), and AR/TR (100%; P less than 0.01) were higher in CAPD than in HD. IR and TR were not different in the two groups. Plasma 18-OH-B was normal in HD but markedly elevated in CAPD. 18-OH-B was higher in CAPD than in HD at 8 AM (P less than 0.05) and at 12 noon (P less than 0.05). Plasma cortisol was not different in the two groups. We conclude that the greater degree of renin activation in CAPD versus HD contributes to the higher levels of 18-OH-B and PAC observed in CAPD patients.     

Management of coronary artery bypass grafting surgery by continuous ambulatory peritoneal dialysis in a patient with chronic renal failure under hemodialysis

A 64-year-old patient with chronic renal failure underwent coronary artery bypass grafting (CABG) because of the frequent severe angina during hemodialysis. Intraoperative hemodialysis and extra-corporeal ultrafiltration method (ECUM) was used during cardiopulmonary bypass. Postoperative management was successfully performed by continuous ambulatory peritoneal dialysis (CAPD), which made hemodynamics stable and prevented postoperative bleeding, providing with adequate fluid removal and satisfactory control of serum chemistry.     

Mycobacterium fortuitum peritonitis in two patients receiving continuous ambulatory peritoneal dialysis

We present two cases of non-resolving peritonitis treated with a standard peritonitis protocol. The organism identified from the peritoneal effluent was Mycobacterium fortuitum, a group IV (Runyon's classification) rapidly growing, nontuberculous mycobacterium. M. fortuitum is ubiquitous and can be isolated from a number of natural sources. Risk factors these two patients had for developing M. fortuitum peritonitis included underdialysis, the immunocompromised state associated with end stage renal disease, prior or prolonged broad spectrum antibiotic treatment, and possible exposure to environmental factors, since both were hospitalized at about the same time. The isolates were resistant to the conventional antibiotics recommended for the treatment of this mycobacterium. Both patients, however, responded to catheter removal and antibiotics administered according to the sensitivities of the mycobacterium isolated. Copyright Copyright 1999 S. Karger AG, Basel     

Eating behavior in continuous ambulatory peritoneal dialysis and hemodialysis patients.

Three groups consisting of 12 subjects each (continuous ambulatory peritoneal dialysis [CAPD] patients, hemodialysis patients, and healthy controls) matched for age, sex, and body weight were invited to a test meal for the study of hunger, fullness, and food preferences. They were served an excess portion of hash served on a plate placed on a hidden scale ("VIKTOR"), which was connected to a computer registering the eating process on-line. The patients filled in visual analogue scales (VAS) concerning appetite and food preferences before and after the test meal. Mean total intake of food (+/- SD) was significantly higher for healthy controls (357 +/- 175 g) compared with hemodialysis patients (295 +/- 105 g), which in turn was higher than in CAPD patients (206 +/- 70 g). Eating velocity was lower in both dialysis groups compared with controls. CAPD patients experienced less hunger and desire to eat compared with hemodialysis patients and controls. The reason for the low eating drive in CAPD patients despite their great need for protein and calories is unknown, but might be explained by gastric retention, insufficient dialysis, metabolic effects of the high sugar load from the dialysate, or combinations of these factors.     

Neurotoxicity of acyclovir in patients with end-stage renal failure treated with continuous ambulatory peritoneal dialysis.

We report two cases of herpes-zoster in which the administration of acyclovir to patients with end-stage renal failure treated by continuous ambulatory peritoneal dialysis (CAPD) resulted in acyclovir neurotoxicity, even though the doses administered were within those recommended by the manufacturer's data sheet for patients with renal failure. Acyclovir removal was negligible with peritoneal dialysis and one patient died. The other patient was successfully treated with hemodialysis, which effectively reduced plasma concentrations, resulting in an improvement in conscious state. Acyclovir neurotoxicity should be considered in patients with renal failure who have been treated for viral infections, in whom the conscious state has deteriorated despite normal brain computed tomography (CT) scan and lumbar puncture investigations. Hemodialysis is the preferred treatment for the rapid removal of acyclovir.