Peritonitis-related mortality in patients undergoing chronic peritoneal dialysis.

Peritonitis is a well-known cause of mortality in peritoneal dialysis (PD) patients. We carried out a retrospective study to disclose the clinical spectrum and risk profile of peritonitis-related mortality. We analyzed 693 episodes of infectious peritonitis suffered by 565 patients (follow-up 1149 patient-years). Death was the final outcome in 41 cases (5.9% of episodes), peritonitis being directly implicated in 15.2% of the global mortality and 68.5% of the infectious mortality observed. In 41.5% of patients with peritonitis-related mortality, the immediate cause of death was a cardiovascular event. Highest mortality rates corresponded to fungal (27.5%), enteric (19.3%), and Staphylococcus aureus (15.2%) peritonitis. Multivariate analysis disclosed thatthe baseline risk of peritonitis-related mortality was significantly higher in female [relative risk (RR) 2.13, 95% confidence interval (CI) 1.24-4.09, p = 0.02], older (RR 1.10/year, CI 1.06-1.14, p < 0.0005), and malnourished patients (RR 2.51, CI 1.21-5.23, p = 0.01) with high serum C-reactive protein (s-CRP) levels (RR 4.04, CI 1.45-11.32, p = 0.008) and a low glomerular filtration rate (RR 0.75 per mL/minute, CI 0.64 -0.87, p < 0.0005). Analysis of risk after a single episode of peritonitis and/or subanalysis restricted to peritonitis caused by more aggressive micro-organisms disclosed that overall comorbidity [odds ratio (OR) 1.21, CI 1.05-1.71, p = 0.005], depression (OR 2.35, CI 1.14-4.84, p = 0.02), and time on PD at the time of the event (OR 1.02/month, CI 1.00-1.03, p = 0.02) were other predictors of mortality. In summary, the etiologic agent is a definite marker of peritonitis-related mortality but gender, age, residual renal function, inflammation (s-CRP), malnutrition, and depression are other significant correlates of this outcome. Most of these risk factors are common to cardiovascular and peritonitis-related mortality, which may explain the high incidence of cardiovascular event as the immediate cause of death in patients with peritonitis-related mortality.

Compared time profiles of ultrafiltration, sodium removal, and renal function in incident CAPD and automated peritoneal dialysis patients.

BACKGROUND: Fluid and sodium removal rates may not be equivalent in patients undergoing automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD). This may influence compared cardiovascular outcomes in both groups. METHODS: The authors compared prospectively the time courses of ultrafiltration, sodium removal, and residual renal function (RRF) in a group of incident patients treated with CAPD (n = 53) or APD (n = 51) for at least 1 year (mean follow-up, 28.9 months; range, 13 to 62). The authors analyzed potential effects of these factors on blood pressure (BP) control and cardiovascular morbidity and mortality. RESULTS: Ultrafiltration and sodium removal rates were consistently lower in APD patients (mean differences, 236 mL/d; P = 0.012, and 36 mmol/d; P = 0.018, respectively, end of first year). Moreover, univariate and multivariate analysis indicated that APD therapy results in a moderate, but significantly faster decline of RRF than CAPD therapy. Analysis of clinical outcomes showed that CAPD (versus APD) therapy or higher ultrafiltration or sodium removal rates were associated with a better time course of systolic, but not diastolic, BP. We were unable to identify PD modality, ultrafiltration, or sodium removal rates as independent predictors of cardiovascular morbidity and mortality. CONCLUSION: Ultrafiltration and sodium removal rates are consistently lower in incident APD patients than in their counterparts undergoing CAPD. Moreover, RRF declines faster during APD than during CAPD therapy, although this difference may be partially counteracted by a detrimental effect of ultrafiltration on RRF. Aside from a better control of systolic BP in CAPD patients, these differences do not portend significant cardiovascular consequences during the first years of PD therapy.

Incidence and significance of peritoneal eosinophilia during peritoneal dialysis-related peritonitis.

OBJECTIVE: To determine the incidence and significance of peritoneal eosinophilia (PEo) during peritoneal dialysis (PD)-related peritonitis. DESIGN: Retrospective observational study. SETTING: Tertiary-care public hospital. PATIENTS AND METHOD: We performed a cytological study of dialysate at the start of 465 cases of peritonitis diagnosed between January 1987 and May 2002. Cases associated with PEo (> 10% eosinophils) were classified according to their infectious or seemingly noninfectious origin. We compared the two groups, trying to disclose differentiating patterns of presentation. RESULTS: We found PEo in 42 cases. Infectious peritonitis was the final diagnosis in 22 of the 42 cases; a diagnosis of idiopathic eosinophilic peritonitis was finally established in 20 cases. The etiologic spectrum of infectious peritonitis with PEo did not differ markedly from the global spectrum of peritonitis in our unit. Infectious peritonitis with PEo tended to appear later in the course of PD therapy, presented with more severe clinical symptoms, displayed higher total peritoneal leukocyte and neutrophil counts, and showed lower degrees of PEo than idiopathic eosinophilic peritonitis, but overlap between the groups was significant. CONCLUSIONS: Peritoneal eosinophilia is infrequent but not rare during infectious PD-related peritonitis. Our findings agree with established concepts on idiopathic eosinophilic peritonitis, but overlap in presentation with infectious eosinophilic peritonitis is significant, which should be taken into consideration at the time of planning therapy for this condition.

Acute plasma ghrelin and leptin responses to oral feeding or intraperitoneal hypertonic glucose-based dialysate in patients with chronic renal failure.

BACKGROUND: Chronic renal failure (CRF) is associated with increased plasma levels of ghrelin and leptin, but the regulation of the secretion of these hormones has been insufficiently studied, in this setting. The aim of this study was to analyze the acute effects of oral feeding or intraperitoneal 3.86% glucose-based dialysate infusion on plasma ghrelin and leptin levels in patients with CRF undergoing peritoneal dialysis (PD). METHODS: Following a crossover design, 10 patients and eight healthy controls underwent a standardized oral intake, a 3.86% glucose-based dialysate PD exchange (patients) and placebo oral intake. We scrutinized acute changes in plasma ghrelin, leptin, glucose, insulin, and growth hormone (GH) levels. RESULTS: In patients, total ghrelin decreased modestly immediately after oral feeding (nadir 90.6% of baseline, range 85.1, 94.5, P= 0.03) or the PD exchange test (92.2%, range 58.7, 101.9, P= 0.05) (median). Response to oral feeding was markedly blunted when compared with healthy individuals (73.8%, range 56.1, 89.1, P= 0.007) (P < 0.005 vs. patients). Plasma acyl-ghrelin had a less marked but more persistent decay after the PD exchange test (nadir 80.4%, range 55.1, 96.3, P= 0.02) than after oral intake (64.4%, range 45.6, 82.3, P= 0.005); again, changes were more intense in normal controls (47.4%, range 32.1, 67.3, P= 0.01) (P < 0.05 vs. patients). Leptin levels decreased slightly (P < 0.05) after the PD exchange in patients, but did not respond acutely to oral feeding in patients or controls. CONCLUSION: Ghrelin secretion is partially refractory to the acute inhibitory effect of oral feeding in patients with CRF undergoing PD therapy. A 3.86% glucose-based PD exchange results in a significant decrease of plasma ghrelin levels. Plasma leptin levels are not acutely affected by oral feeding in patients with CRF or healthy individuals.