Exit-site infection in continuous ambulatory peritoneal dialysis: a review.

Although the ability of CAPD to successfully treat end-stage renal disease is now well established, exit-site infection (ESI) remains a serious cause of morbidity. The objective of this article is to review recent advancements relating to ESI pathogenesis and its reduction. Current definitions of ESI are reviewed, as are comparative studies of etiology. Emphasis is placed on the literature identifying Staphylococcus aureus as the primary cause of ESI in CAPD. The article reviews reported rates of ESI and discusses reasons for variations of this complication's reported frequency. The selection of catheters available in CAPD are discussed, as are studies demonstrating the threat of S. aureus to catheter survival. The pathogenesis of exit-site infection related to S. aureus nasal carriage in CAPD is reviewed in light of recent findings indicating the pre-CAPD nasal carrier as the patient at risk for subsequent ESI. Postoperative and long-term care of the catheter patient are reviewed for various literature protocols. Treatment recommendations for choice of agents are discussed. Future research should include a better understanding of the morphology of the CAPD catheter exit-site in humans and the healing process. ESI epidemiological studies should be encouraged in tandem with well-designed, controlled studies on the value of prophylactic treatment.     

Chronic peritoneal dialysis in juvenile-onset diabetes mellitus: a comparison with hemodialysis.

Fourteen juvenile-onset diabetic patients accepted for renal transplantation and maintained on chronic peritoneal dialysis during a 3-year period were compared with a similar group of 43 patients accepted for renal transplantation and maintained on hemodialysis. The 1-year survival in each group was similar (52% on chronic peritoneal dialysis; 55% on hemodialysis), but there was a striking difference in progressive morbidity. Seven patients on chronic peritoneal dialysis were blind in one or both eyes at the onset, and visual acuity improved in two, including one bilaterally blind patient who achieved 20/35 vision bilaterally; none worsened. In the hemodialysis group, 12 patients were totally blind in one or both eyes and 11 additional patients became blind or had severe deterioration in vision; none improved. Neuropathy progressed in only 1 patient on chronic peritoneal dialysis, whereas it worsened in 17 patients on hemodialysis--9 to the extent that they needed braces or canes or were nonambulatory. All patients on chronic peritoneal dialysis were home trained and were dialyzed at night, with seven being able to work full or part time; virtually none of the patients on hemodialysis were able to work. Chronic peritoneal dialysis was relatively free of technical complication, and no significant difficulty was encountered in diabetic control, in the anephric state, or during abdominal surgery. Chronic peritoneal dialysis appears to have less associated morbidity than does hemodialysis in the treatment of chronic renal failure of juvenile-onset diabetes mellitus.     

Chronic peritoneal dialysis catheters in children: a fifteen-year experience of the Italian Registry of Pediatric Chronic Peritoneal Dialysis.

OBJECTIVE: To analyze data on 503 chronic peritoneal dialysis (CPD) catheters implanted between 1986 and 2000 in pediatric patients enrolled in the Italian Registry of Pediatric Chronic Peritoneal Dialysis (the Registry), comparing three different time periods: 1986-1990, 1991-1995, and 1996-2000. DESIGN: Retrospective study. SETTING: 23 dialysis centers participating in the Registry. METHODS: Data were collected from questionnaires filled in every year. The information for each peritoneal catheter included type, site and technique of insertion, exit-site orientation, exit-site care, complications, survival, and reason for removal. PATIENTS: 503 catheters were implanted in 363 pediatric patients aged younger than 15 years at the start of CPD: 97 catheters in patients under 2 years of age, 67 in patients aged 2-5 years, and 339 in patients over 5 years of age. Mean patient age at onset of CPD was 8.0 +/- 5.1 years. All catheters were surgically implanted and omentectomy was performed in 82.4% of cases. The catheters used were Tenckhoff [468 (93.0%): 443 double cuff, 25 single cuff] and double-cuffed Valli [35 (7.0%)]. The entry site was in the midline in 153 cases (30.4%) and paramedian in 350 (69.6%). RESULTS: During 9048 dialysis-months we observed 451 catheter-related complications, yielding an incidence of 1 episode/20.1 CPD-months: 330 catheter infections (exit-site and/or tunnel infections), 26 leakages, 26 dislocations, 24 obstructions, 22 cuff extrusions, 6 hemoperitoneums, 17 others. 171 catheters were removed due to catheter-related causes; exit-site and/or tunnel infections were the main cause for removal (75.4%), followed by obstruction, dislocation, outer-cuff extrusion, and leakage. Younger children (< 2 years) had a higher risk of infectious causes of catheter removal compared to children aged 2-5 years (p = 0.004) and over 5 years of age (p = 0.002). During the 15-year observation period, a significant reduction in the incidence of leakage was observed and risk of leakage was lower in catheters with paramedian entry site compared to catheters with midline entry site. Removal and replacement of peritoneal catheters during the same surgical operation was performed in 76.3% of catheter removals. Catheter survival rate was 78.1% at 12 months, 58.5% at 24 months, 43.8% at 36 months, and 34.6% at 48 months. No difference in catheter survival was observed in younger children (< 2 years) compared with the two other age groups: < 2 years versus 2-5 years hazard ratio 0.7, 95% confidence interval (95%CI) 0.4-1.2; < 2 years versus > 5 years hazard ratio 0.8, 95%CI 0.5-1.1. CONCLUSIONS: In this survey, we observed better catheter survival in comparison with data reported by the Registry in 1998. Catheter survival improved especially in younger children (< 2 years), a group that previously had a decreased catheter survival rate compared to older age groups. In addition to the progressive increase in experience acquired by dialysis centers, this upward trend may also be related to greater use of double-cuffed catheters, with paramedian exit site, and a higher frequency of omentectomy.     

Continuous ambulatory peritoneal dialysis and haemodialysis in the elderly

The clinical course and outcome of 58 patients receiving haemodialysis or continuous ambulatory peritoneal dialysis aged 65 years and above at the start of dialysis treatment was examined over a six-year period. Method of presentation and mode of treatment did not affect survival, but the presence of ischaemic heart disease or congestive cardiac failure was significantly associated with increased mortality. The actuarial two-year patient survival was 54 per cent. Survival on continuous ambulatory peritoneal dialysis was 75 per cent, and the incidence of peritonitis was one episode per 7.36 patient-treatment months. The mean duration of hospital admission was 57.2 days per patient year for continuous ambulatory peritoneal dialysis, and 19.9 days per patient year for haemodialysis patients.     

Inflammation in peritoneal dialysis: a Latin-American perspective.

Peritoneal dialysis (PD) patients present an extremely high mortality rate, but the mechanisms mediating the increased risk of mortality observed in this group of patients are still largely unknown, which limits the perspective of effective therapeutic strategies. The leading hypothesis that tries to explain this high mortality risk is that PD patients are exposed to a number of traditional risk factors for cardiovascular disease (CVD) already at the onset of their chronic kidney disease (CKD), since many of these risk factors are common to both CVD and CKD. Of particular importance, chronic inflammation recently emerged as an important novel risk factor related to multiple complications of CKD. There are many stimuli of the inflammatory response in CKD patients, such as fluid overload, decreased cytokine clearance, presence of uremia-modified proteins, presence of chronic infections, metabolic disturbances (including hyperglycemia), obesity. Many of these factors are related to PD. Latin America has made some progress in economic issues; however, a large portion of the population is still living in poverty, in poor sanitary conditions, and with many health-related issues, such as an increasing elderly population, low birth weights, and increasingly high energy intake in the adult population, which, in combination with changes in lifestyle, has provoked an increase in the prevalence of obesity, diabetes, and CVD. Therefore, in Latin America, there seems to be a peculiar situation combining high prevalence of low education level, poor sanitary conditions, and poverty with increases in obesity, diabetes, and sedentary lifestyle. Since inflammation and mortality risk are intimately related to both sides of those health issues, in this review we aim to analyze the peculiarities of inflammation and mortality risk in the Latin-American PD population.     

Chronic peritoneal dialysis in South Asia - challenges and future.

Chronic peritoneal dialysis (PD), especially continuous ambulatory PD (CAPD), is being increasingly utilized in South Asian countries (population of 1.4 billion). There are divergent geopolitical and socioeconomic factors that influence the growth and expansion of CAPD in this region. The majority of the countries in South Asia are lacking in government healthcare system for reimbursing renal replacement therapy. The largest utilization of chronic PD is in India, with nearly 6500 patients on this treatment by the end of 2006. A large majority of patients are doing 2 L exchanges 3 times per day, using glucose-based dialysis solution manufactured in India. Chronic PD is not being utilized in Myanmar, Bhutan, or Seychelles. Affirmative action by the manufacturing industry, medical professionals, government policy makers, and nongovernmental organizations for reducing the cost of chronic PD will enable the growth and utilization of this life-saving therapy.     

Chronic inflammation in peritoneal dialysis: the search for the holy grail?

Mortality and morbidity in chronic kidney disease (CKD) patients are unacceptably high. The annual mortality rate due to cardiovascular disease (CVD) is approximately 9%, which, for the middle-aged person, is at least 10- to 20-fold higher than for the general population. Classic risk factors for CVD are highly prevalent in CKD patients, but they cannot fully account for the excessive rate of CVD in this population. Instead, it has become increasingly clear that nontraditional risk factors, such as systemic inflammation, may play a key role in the development of atherosclerosis. It is well established that inflammatory markers are very powerful predictors of high CVD morbidity and mortality not only in the general population, but particularly in CKD patients. Signs of a sustained low-grade inflammation, such as increased levels of C-reactive protein (CRP), are present in the majority of stage 5 CKD patients, even in patients in clinically stable condition, and they are also commonly observed after the initiation of dialysis therapy. Dialysis therapy--hemodialysis as well as peritoneal dialysis (PD)--may itself contribute to systemic inflammation. Local intraperitoneal inflammation can also occur in patients treated with PD. These local effects may result in a low-grade inflammation, caused by the bioincompatibility of conventional glucose-based dialysis fluids, to intense inflammation associated with peritonitis. Given these circumstances, it is reasonable to hypothesize that strategies aiming to reduce inflammation are potentially important and novel, and could serve to reduce CVD, thereby lowering morbidity and mortality in patients with CKD. In this review we provide information supporting the hypothesis that systemic inflammation is tightly linked to the most common complications of CKD patients, in particular those on PD, and that local inflammation in PD may contribute to various related complications. The aims of this review are to discuss the reasons that make inflammation an attractive target for intervention in CKD, the particular aspects of the inflammation-CVD axis during PD treatment that are likely involved, and possible means for the detection and management of chronic inflammation in PD patients.     

Brucella peritonitis in peritoneal dialysis: a case report and review of the literature

Brucellosis is a zoonotic infection that humans contract usually by ingestion of unpasteurized milk and milk products or by direct contact with raw infected animal products. Infection is endemic in many countries, including Turkey. Being a systemic disease, brucellosis may affect almost any part of the body. The peritoneum is a site rarely involved in brucellosis. Most peritonitis episodes involving Brucella species have been spontaneous cases reported in cirrhotic patients with ascites. To our knowledge, the literature contains only 5 cases of Brucella peritonitis related to continuous ambulatory peritoneal dialysis. Here, we report Brucella peritonitis in a continuous ambulatory peritoneal dialysis patient, and we discuss the relevant literature.     

High prevalence of hyperparathyroidism among peritoneal dialysis patients: a review of 176 patients.

OBJECTIVES: Parathyroid dysfunction continues to produce significant morbidity in dialysis patients. Since the introduction of low calcium dialysate for peritoneal dialysis (PD), no large studies have been done to determine the prevalence of parathyroid dysfunction in these patients. This study was done to assess the prevalence of parathyroid disease in the PD population and to determine the risk factors associated with this dysfunction. DESIGN: We analyzed data on 176 patients who received PD at a single center between August 1998 and February 1999. Clinical data, laboratory variables related to parathyroid function, and data pertaining to dialysis treatment and weekly drug dosing were obtained for each patient on two different occasions, approximately 3 months apart. Variables predictive of the development of parathyroid dysfunction were calculated by univariate and multivariate logistic regression analysis. RESULTS: Two-thirds of the patients surveyed had an abnormal intact parathyroid hormone (iPTH) level: 47% had an iPTH level more than three times normal, the mean was 54.6+/-35.4 pmol/L; 23% had an iPTH value below the upper limit of normal, here the mean was 3.6+/-1.8 pmol/L. Diabetic patients had lower iPTH levels (22.2+/-28.4 pmol/L) than nondiabetics (33.9+/-34.8 pmol/L) (p = 0.02). On multivariate regression analysis, we found that age, duration of dialysis, Kt/V, serum bicarbonate, and serum ionized calcium levels did not significantly affect parathyroid function. Hyperphosphatemia was the only factor that was associated with the development of secondary hyperparathyroidism in this study population (p = 0.029). CONCLUSION: There is a high prevalence of hyperparathyroidism in the current PD population. Phosphate control is suboptimal and hyperphosphatemia is an independent risk factor for the development of hyperparathyroidism.     

The utility of a structured evaluation of elderly patients for continuous peritoneal dialysis.

The elderly comprise an increasing proportion of chronic dialysis patients. Recruiting them for continuous peritoneal dialysis (CPD) would help CPD programs maintain a patient population. We retrospectively studied the ability of a prospective evaluation to predict success with CPD in elderly (age greater than 60 years) patients. PD nurses and a renal social worker assigned scores in 10 categories, which were then averaged to obtain an over-all evaluation score. Scores were from 1-5 with 1 = good, 5 = poor, and 3 = average. Thirty-four elderly patients began CPD during the study period. Evaluation scores were available for 28 of these patients before they began dialysis. Evaluation scores less than 3 predicted success with CPD (2.2 +/- 0.2 versus 3.2 +/- 0.4 in patients transferring to hemodialysis, p less than 0.02). Patient motivation and preference were the categories that predicted success with CPD. Elderly patients were more likely than younger patients (those less than 60 years of age) to decline CPD for social reasons (46% versus 4% respectively, p less than 0.001). Elderly patients required more CPD training time than young patients (4.9 +/- 0.7 days versus 3.3 +/- 0.8 days respectively, p less than 0.01). We conclude that a prospective assessment of elderly patients can predict success with CPD and provide information important to individual structuring of CPD training and follow-up.     

The standard peritoneal permeability analysis in the rabbit: a longitudinal model for peritoneal dialysis.

OBJECTIVE: The development of an experimental peritoneal dialysis (PD) model in rabbits to investigate peritoneal transport characteristics during a longitudinal follow-up and to assess normal values of these peritoneal transport parameters. DESIGN: Peritoneal transport parameters were determined in conscious, unrestrained rabbits by standard peritoneal permeability analysis adjusted for rabbits (SPAR). In this test a 1-hour dwell with 3.86% glucose dialysate is used. Dextran 70 (1g/L) was added to the dialysate to allow calculation of fluid kinetics. Dialysate samples were taken before, 10, and 40 minutes after instillation and at the end of the dwell. Blood was drawn at the end of the dwell. EXPERIMENTAL ANIMALS: Eighteen female New Zealand White rabbits (2565 g) were included for catheter implantation. SPARs were performed in 15 animals; the other 3 were excluded due to complications. MAIN OUTCOME: The mass transfer area coefficients (MTACs) of the low molecular weight solutes urea (MTAC(urea)) and creatinine (MTACcr) were calculated.The clearances of albumin (CIalb) and IgG (CI(IgG)), glucose absorption, and fluid transport were computed. Coefficients of intraindividual variation (Vc) were calculated for these parameters. RESULTS: The main complications were catheter obstruction and/or dislocation. Five rabbits underwent uncomplicated PD during a 4-week period. Fifteen SPARs in 15 stable rabbits were performed and analyzed to obtain normal values. Means and standard deviations of the transport parameters were as follows: MTAC(urea) 2.24+/-0.57 mL/min, MTACcr 1.61+/-0.30 mU/min, CI(alb) 52.9+/-17.2 microL/min, CI(IgG) 44.5+/-22.9 UL/min. The transcapillary ultrafiltration rate was 0.66+/-0.13 mL/min and the lymphatic absorption rate 0.47+/-0.26 mL/min. The parameters of solute transport were upscaled to those in humans using two different methods. MTACs of low molecular weight solutes in rabbits and patients were of the same order of magnitude, but the clearance of albumin was approximately four times higher in rabbits than in patients, and that of IgG eight times. In all rabbits sieving of sodium was observed. The dialysate/plasma (D/P) of sodium decreased to a minimum at 40 min (p<0.003 vs the initial value), followed by a rise to 60 min.The minimal value was 0.884+/-0.002. The coefficients of variation calculated on 7 rabbits that underwent two or more SPARs were similar to those assessed from the patient data. This indicates stability of the model and reproducibility of the SPAR. CONCLUSION: The conscious rabbit model for PD can be used for repeated studies on peritoneal transport.     

Oral protein-energy supplements in peritoneal dialysis: a multicenter study.

BACKGROUND: Protein-energy malnutrition is prevalent in peritoneal dialysis (PD) patients and is associated with increased morbidity and mortality. OBJECTIVE: To evaluate the impact of prophylactic treatment with an oral protein-energy supplement (Protenplus; Fresenius AG, Bad Homburg, Germany) on nutritional parameters in patients starting PD. DESIGN: Prospective, multicenter, randomized study of group A patients (Protenplus, n = 35) and group B (controls, n = 30), with evaluations at baseline and at 6 and 12 months. Statistical Methods: Efficacy of factors by linear mixed model analysis for repeated measurements, chi-square, t-test, and Mann-Whitney test. OUTCOME PARAMETERS: Patient compliance, serum albumin, and other nutritional parameters. RESULTS: No significant differences were found at baseline evaluation. During follow-up, a significant number of group A patients abandoned intake of the supplement due to non-compliance (n = 7) or side effects (n = 8) (chi2 p < 0.01). Patients with lower residual renal function were less likely to comply. The mixed model in the "intention to treat" analysis showed a significant increase related to supplement intake only in total lymphocyte count in group A. The "as treated" analysis of the 29 patients who fulfilled the study (9 in group A, 20 in group B) disclosed that belonging to group A constituted an independent factor for increased lymphocyte count (p < 0.001), body weight (p < 0.03), tricipital skinfold thickness (p < 0.01), middle-arm muscle circumference (p < 0.025), lean body mass (LBM) (p < 0.002), creatinine LBM related to body surface area (p < 0.001), and creatinine generation rate (p < 0.002). However, these data may have been biased by the high rate of noncompliance in group A. CONCLUSIONS: Protenplus proved to be unsuitable as a long term, oral protein-energy supplement in PD patients due to a high rate of noncompliance and intolerance, primarily among patients with lower residual renal function. The question of whether other products, better-tolerated as nutritional supplements, could compensate for daily protein peritoneal losses in long-term PD remains open.