Transperitoneal water transport before, during, and after episodes with infectious peritonitis in patients treated with CAPD.
ABSTRACT Peritonitis is considered to change peritoneal permeability and influences the long-term change in permeability during peritoneal dialysis. The objective of this study is to evaluate water transport across the peritoneum, expressed as drained ultrafiltration volume, before, during, and after episodes of peritonitis.
A retrospective analysis of data from a group of patients was performed in which drained ultrafiltration volume and glucose concentration in dialysis fluid were recorded for each dwell time every day during time on continuous ambulatory peritoneal dialysis treatment as a part of the clinical routine performed. Days with peritonitis and average of daily measurements 1 month before and after each peritonitis episode were evaluated separately for day and night exchanges. In all, 64 episodes of peritonitis in 30 patients were included in this study. Approximately 15,000 exchanges were recorded. Paired t-test and repeated-measures analysis of variance were performed.
Compared with the average for the previous month, there was a significant decrease in ultrafiltration volume for day exchanges occurring 2 days before the appearance of other clinical symptoms of peritonitis (P = 0.029). For night exchanges, the decrease in ultrafiltration volume occurred 24 hours before diagnosis (P < 0.001). Ultrafiltration volume was at its minimum the day of diagnosis for both the day (P < 0.001) and night (P < 0.001) exchanges compared with average volume for the previous month. Ultrafiltration volumes remained low for 2 days after diagnosis during both the day (P = 0.009) and night (P = 0.017) exchanges. Relative to the previous month, glucose concentration on the day of clinical diagnosis of peritonitis did not differ significantly (P = 0.328 and P = 0.963 for day and night shifts, respectively). Overall, no significant changes in ultrafiltration volumes or glucose concentrations from the month before to the month after the peritonitis episode were found (P = 0.99 and P = 0.27 for measurements during the day, respectively).
Osmotic forced ultrafiltration decreased during infectious peritonitis, most significantly for a long dwell time, consistent with an increase in both functional peritoneal surface area and hydraulic conductivity. This finding appeared 2 days before other clinical symptoms and remained significantly low 2 days after diagnosis.
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ABSTRACT: In long-term peritoneal dialysis (PD) morphological and functional changes of the peritoneal membrane are common. Sub-mesothelial fibrosis, angiogenesis and vasculopathy are typical histomorphological alterations of the peritoneal membrane, which, to a certain degree, are induced by uremia and recurrent peritonitis. The most important causative factor, however, represents the chronic exposure to PD solutions. Glucose, glucose degradation products and advanced glycation end-products (AGEs) via different pathways induce inflammation, fibrosis and angiogenesis. As a functional consequence ultrafiltration failure due to peritoneal hyperpermeability and an increased effective peritoneal surface area represents a major clinical problem. An insufficient function of the water-selective aquaporin 1 (AQP-1) channel may also be causative for inadequate ultrafiltration. A rare but life-threatening complication of long-term PD is encapsulating peritoneal sclerosis (EPS). For both impaired AQP-1 function and EPS, the long-term effects of PD fluids are believed to be responsible, even though the mechanisms are not yet understood. The avoidance of glucose and modern PD fluids with fewer glucose degradation products, as well as first pharmacological attempts may help to preserve the peritoneal membrane in the long term.Pediatric Nephrology 02/2008; 23(1):19-25. · 2.94 Impact Factor
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ABSTRACT: The natural course of longitudinal changes in peritoneal permeability and membrane area has been studied mostly by performing single-dwell studies in selected patients during treatment with peritoneal dialysis. To evaluate the permeability characteristics of the peritoneal membrane by measuring drained ultrafiltration volume relative to initial glucose concentration in dialysis fluid from the start to the end of continuous ambulatory peritoneal dialysis (CAPD) treatment in a selected cohort of patients with and without peritonitis. A retrospective analysis of a group of patients whose peritoneal function was prospectively followed by recording drained ultrafiltration volume and glucose concentration in dialysis fluid for each dwell time, every day, during the time in CAPD treatment. Mean values from a 1-month period starting after the first 3 weeks of CAPD treatment were compared with the mean values from the last month of treatment. Approximately 11 500 exchanges were analyzed. Evaluations were done separately for short (day) and long (night) dwell times. PATIENTS AND STATISTICS: Of 132 patients commencing CAPD treatment in the time period selected for inclusion, 51 had enough data to be included in this study. Of these, 29 patients experienced one or more episodes of successfully treated peritonitis. The selection of patients was not based upon patient characteristics, but upon criteria to satisfy predefined demands, such as number of measurements in each period, time since an episode of peritonitis, and time on CAPD treatment. Data were analyzed in three different groups: patients with episodes of peritonitis, patients without peritonitis, and both groups together. To assess changes between monthly mean at the start and at the end of CAPD, paired t-test was performed. Patients were also stratified into two groups according to low and high glucose in dialysis fluid at the start of CAPD (cutoff = 2 g/dL). Additionally, we used linear regression analyses to predict the level of drained ultrafiltration volume for a given level and change in glucose concentration. Mean treatment time for the entire group was 20 months (median 14.3 months), ranging from 6 to 69 months. No statistical differences in glucose concentrations were found between the periods compared. In the entire group there was an increase in ultrafiltration volume from the start to the end of CAPD treatment, for both day (p = 0.009) and night (p = 0.013) exchanges. Also, for patients without peritonitis, an increase appeared for day (p = 0.046) and night exchanges (p = 0.053). However, for the cohort with peritonitis, only an insignificant increase was indicated. Patient characteristics, diabetic patients, the need for glucose in dialysis fluid when commencing CAPD treatment, the number of episodes of peritonitis, and time on CAPD did not influence the change in ultrafiltration. Regression analyses showed higher ultrafiltration response to a given level and change in glucose concentration at the end of CAPD treatment compared to the start values, also for the cohort with peritonitis. The regression coefficient between these variables was also significantly changed for both day (p < 0.0001) and night (p = 0.027) exchanges. A significant change in the regression coefficient between glucose in dialysis fluid and ultrafiltration volume reflects an increase in ultrafiltration response to a given level and change in glucose concentration during time on CAPD treatment. A parallel change after 5- and 9-hour dwells can be explained by a decrease in peritoneal surface area combined with a lesser decrease in peritoneal conductivity. However, changes in Starling forces across the peritoneal membrane are possible even in the absence of changes in peritoneal membrane characteristics.Peritoneal dialysis international: journal of the International Society for Peritoneal Dialysis 24(6):571-9. · 2.21 Impact Factor
- Der Nephrologe 01/2007; 2(2):90-99.