bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmacokinetics of Intraperitoneal Cefazolin and Gentamicin in Empiric Therapy of Peritonitis in Continuous Ambulatory Peritoneal Dialysis Patients
Authors: Tosukhowong Thanawat , Eiam–Ong Somchai , Thamutok Kannika , Wittayalertpanya Supeecha , Ayudhya Duangchit Panomvana Na 
Published: February 2020

Objective The aim of this study was to measure and evaluate the appropriateness of the actual concentrations of serum and dialysate cefazolin and gentamicin in Thai continuous ambulatory peritoneal dialysis (CAPD) patients treated following the International Society for Peritoneal Dialysis (ISPD) 1996 recommendations for the empiric therapy of CAPD-related peritonitis. Design Prospective and descriptive study. Setting Institutional level of clinical care. Patients CAPD-related peritonitis patients were diagnosed by dialysate effluent white cell count of more than 100/mm3 and polymorphonuclear leukocytes of at least 50%. There were 18 patients, all at least 15 years of age, entered; all completed the study. Intervention In accordance with the ISPD 1996 recommendations, the antibiotic regimen included continuous intraperitoneal (IP) cefazolin and once-daily IP amino-glycoside. Cefazolin was administered as loading and continuous maintenance doses of 500 and 125 mg/L dialysate, respectively. Gentamicin, 0.6 mg/kg body weight, was given IP once daily. Duration of treatment was 120 hours. Main Outcome Measures Serum and dialysate effluent samples of the 18 CAPD patients with peritonitis were measured and used for the synthesis of pharmacokinetic equations that could predict drug concentrations at any treatment time. Results Following administration according to the ISPD 1996 treatment recommendations, serum cefazolin reached levels higher than the recommended levels (8 mg/mL) at 3.3 minutes after drug administration, and persisted through the 5-day duration of the study. Dialysate cefazolin levels during the studied period also were persistently higher than the recommended values. The peak serum gentamicin levels were lower than the suggested values of 4 mg/mL, whereas the trough serum gentamicin levels were higher than the minimal toxic concentrations (2 mg/mL). Dialysate gentamicin levels were higher than therapeutic concentrations for only 4.75 hours in each day. It was difficult, using pharmacokinetic studies, to adjust the dosage regimen of gentamicin to achieve appropriately therapeutic levels in both serum and dialysate. Conclusions The ISPD 1996 recommended dosage of continuous IP cefazolin could be appropriate for the treatment of CAPD-related peritonitis. Once-daily IP gentamicin administration, however, has less therapeutic benefit and should be re-evaluated.
The Role of Extracellular Matrix in Transperitoneal Transport of Water and Solutes
Authors: Flessner Michael F. 
Published: February 2020

♦ Objective To define the extracellular matrix (ECM), to discuss the physical properties of its components and their impact on transport, and to review data in humans and in animals on the importance of hyaluronan to peritoneal dialysis. ♦ Methods Literature survey. ♦ Results The ECM fills the interstitium between parenchymal cells and blood vessels in the subperitoneal interstitium. It is responsible for the interstitial resistance to solute and water transfer through the peritoneal barrier. Major components are collagen and hyaluronan, which are synthesized locally in the peritoneal tissue. Synthesis and deposition of these components increase with inflammation, and concentrations of the components influence the mechanical properties of the tissue and the interstitial Starling forces as well as transport. Removal of hyaluronan appears to increase the rates of water and large-solute transport. Addition of hyaluronan to dialysate appears to enhance fluid recovery and to reduce protein loss. ♦ Conclusion Many of the physicochemical properties of ECM components are well described, but a large knowledge gap remains concerning the in vivo consequences of specific alterations in the interstitial components. More research is needed.
Influence of Neutral-Ph Dialysis Solutions on the Peritoneal Membrane: A Long-Term Investigation in Rats
Authors: Wieczorowska–Tobis Katarzyna , Polubinska Alicja , Schaub Thomas P. , Schilling Holger , Wisniewska Justyna , Witowski Janusz , Passlick–Deetjen Jutta , Breborowicz Andrzej 
Published: February 2020

♦ Objective Glucose degradation products (GDPs) and low pH are potential causes of bioincompatibility of peritoneal dialysis fluids (PDFs). The aim of the present study was to compare the effect of 6 weeks’ exposure of the peritoneum in rats to two different PDFs: a standard PDF with a low pH and high level of GDPs (CAPD 3: Fresenius Medical Care, Bad Homburg, Germany), and a modified PDF with a low level of GDPs and a physiologic pH (CAPD 3 Balance: Fresenius Medical Care). ♦ Methods After catheter implantation, rats were exposed twice daily for 6 weeks to CAPD 3 fluid or to CAPD 3 Balance. At the beginning and at the end of the study, a 4-hour dwell was performed in every rat to evaluate intraperitoneal inflammation and its effect on total collagen synthesis in the in vitro cultured rat mesothelial cells ( ex vivo study). Additionally, after 6 weeks’ exposure, the peritoneal cavity was opened, and macroscopic changes were evaluated according to a semiquantitative scale. Peritoneal samples were also taken for morphology study. ♦ Results In rats treated with CAPD 3 fluid, intraperitoneal inflammation was comparable at the beginning and at the end of the experiment. In animals exposed to CAPD 3 Balance, the intensity of the intraperitoneal inflammation decreased during the study (cell count, p = 0.0781; neutrophil:macrophage ratio, p < 0.01; nitrite concentration, p < 0.05; hyaluronan level, p < 0.05). The capacity of effluent dialysate from CAPD 3 rats to activate collagen synthesis in in vitro–cultured mesothelial cells was the same at the beginning and at the end of the study. In the CAPD 3 Balance group, this capacity was statistically significantly lower at the end of the study than at the beginning ( p < 0.05). The mean thickness of the visceral peritoneum was comparable in both groups of animals, but, macroscopically, more severe fibrosis was found in the peritoneum of rats exposed to CAPD 3 as compared with animals treated with CAPD 3 Balance ( p < 0.05). ♦ Conclusion We showed that, in the rat model of peritoneal dialysis, chronic exposure of the peritoneum to PDFs with low GDPs and a physiologic pH diminished the intraperitoneal inflammatory reaction induced by dialysis, and reduced peritoneal fibrosis.
Is Growth a Valid Outcome Measure of Dialysis Clearance in Children Undergoing Peritoneal Dialysis?
Authors: Chadha Vimal , Blowey Douglas L. , Warady Bradley A. 
Published: February 2020

♦ Objective Our study evaluated growth as a clinical outcome measure of peritoneal dialysis (PD) adequacy in children with end-stage renal disease (ESRD). ♦ Design This retrospective single-center study was carried out in our tertiary-care medical center. ♦ Patients The study enrolled 24 patients who initiated dialysis after January 1, 1995, and who had been on dialysis for a minimum of 1 year. ♦ Results The weekly mean total [PD + residual renal function (RRF)] creatinine clearance (CCr) and Kt/Vurea were 70.3 ± 18 L per 1.73 m2 and 3.45 ± 0.73, respectively. Of the 24 patients, 12 (50%) were anuric. The mean height standard deviation score (SDS) changed to –1.78 at the end of 1 year from –1.58 at baseline. Catch-up growth (positive Δ height SDS) was observed in 9 patients (37%), 7 of whom (78%) had residual renal function (RRF). In contrast, only 5 of 15 patients (33%) with a negative ΔSDS for height had RRF ( p < 0.025). The mean height SDS in patients with RRF improved to –1.64 from –1.78; in patients without RRF, it worsened to –1.90 from –1.37 ( p = 0.01). While the weekly total Kt/Vurea in patients with RRF (3.53) was similar to that in patients without RRF (3.37, p = 0.6), only the native Kt/Vurea had a significant (but weak) positive correlation with Δheight SDS ( r 2 = 0.17, p = 0.04). In contrast, the total weekly CCr was significantly higher ( p = 0.001) in patients with RRF (81.1 L/1.73 m2) as compared with those without RRF (59.5 L/1.73 m2). However, only the native CCr—and not the dialysis CCr—had a significant (but weak) positive correlation with Δheight SDS ( r 2 = 0.17, p = 0.04). ♦ Conclusions These preliminary data provide evidence for a correlation between solute clearance and growth, with RRF exerting a significant influence on that outcome. The Kt/Vurea data also appear to contradict the presumed equivalence of PD and native clearance in children with ESRD.
Effect in a Rat Model of Heparinized Peritoneal Dialysis Catheters on Bacterial Colonization and the Healing of the Exit Site
Authors: Kim Yong-Lim , Cho Seong , Kim Jun-Chul , Cho Dong-Kyu , Kim Yong-Jin , Larm Olle , Mathiesen Torbjorn , Lindholm Bengt , Bergström Jonas 
Published: February 2020

We performed a prospective, double-blind, randomized study to evaluate whether stable surface heparinization of silicone peritoneal dialysis (PD) catheters prevents bacterial colonization or biofilm formation and improves healing of the exit site. Heparinized catheters were implanted in 20 Sprague–Dawley rats (group H) and non heparinized catheters in another 20 (group C). The PD catheters, constructed of silicon tubing with two polyester cuffs, were patterned after the standard Tenckhoff catheter. A covalent multipoint method of attachment onto polymeric surfaces was used for stable, permanent chemical immobilization of heparin on the PD catheter. Dialysis exchanges (25-mL instillation volume) were performed twice daily for 4 weeks through the permanent catheter. Prophylactic antibiotics were not used. The exit sites were evaluated at 2-week intervals. The extent of biofilm coverage on the intraperitoneal portion of the catheter (obtained at the end of the experiment) was assessed, and sonicated fluid from the catheter tip was cultured for evaluating bacterial colonization of the catheter. Exit-site scores in group H were lower than in group C ( p = 0.052) at the end of week 4. Bacterial colonization tended to be less common in group H [2 of 12 catheters (17%)] than in group C [8 of 15 catheters (53%); p = 0.058], but the extent of biofilm, the peritonitis rate, and the inflammation score of tissue adjacent to the cuff were not different between the groups. Those data suggest that heparinized PD catheters can be a practical approach to the prevention of bacterial colonization and can improve healing of the exit site.
Comparison of the Biocompatibility of Phosphate-Buffered Saline Alone, Phosphate-Buffered Saline Supplemented with Glucose, and Dianeal 3.86%
Authors: Wieczorowska–Tobis Katarzyna , Styszynski Arkadiusz , Breborowicz Andrzej , Oreopoulos Dimitrios G. 
Published: February 2020

Objective We compared the effects of intraperitoneal infusion of phosphate-buffered saline (PBS, pH 7.4), of PBS supplemented with 3.86% glucose (G), and of standard dialysis solution [Dianeal 3.86%: Baxter Healthcare Corporation, Deerfield, IL, U.S.A. (D)] on intraperitoneal inflammation in dialyzed rats. Methods After catheter implantation, rats were infused on day 1 with PBS, on day 3 with PBS+G, on day 5 with D, and on day 7 again with PBS (PBS-2). After a 4-hour dwell, dialysate samples were collected and analyzed. Results All dialysate parameters studied [dialysate cell count, neutrophil:macrophage ratio (Ne:Ma), and total protein], except tumor necrosis factor alpha (TNFα), were comparable during both PBS infusions. During dialysis with PBS+G, the inflammatory response was suppressed as compared with the first dialysis with PBS (cell count, p < 0.001; Ne:Ma, p < 0.05; TNFα, p < 0.001; total protein, p < 0.001). During dialysis with D, peritoneal inflammatory parameters were further suppressed (cell count, p < 0.001 vs PBS and p < 0.01 vs PBS+G; Ne:Ma, p < 0.001 vs PBS and p < 0.05 vs PBS+G; TNFα, p < 0.001 vs PBS and p < 0.001 vs PBS+G; total protein, p < 0.001 vs PBS and p < 0.01 vs PBS+G). Conclusions Hypertonicity of the dialysis fluid suppresses intraperitoneal inflammatory parameters in rats. The suppression was even more severe when Dianeal 3.86% was used. That finding could be due to the low pH and presence of GDPs in the fluid.
Lack of Isoprene Overproduction during Peritoneal Dialysis
Authors: Capodicasa Enrico , Trovarelli Gianfranco , Brunori Federica , Vecchi Luigi , Carobi Carmen , De Medio Gianna E. , Pelli Maria A. , Buoncristiani Umberto 
Published: February 2020

Objective Isoprene is the constitutive unit of isoprenoid lipids and sterols. However, it is also a potential toxic and carcinogenic agent. Recent findings of a marked and prolonged isoprene overproduction induced by hemodialysis sessions raises the question of isoprene behavior in patients on peritoneal dialysis. Design A study with repeated measures per patient and healthy control. Setting Nephrology and Dialysis Unit and Perugia University Medical School. Patients Sixteen consecutive patients on regular continuous ambulatory peritoneal dialysis (CAPD) were evaluated. Endogenous isoprene was analyzed using gas chromatographic assay of breath isoprene, collected at set times before and after dialysis fluid exchange. Results No significant variations were found in breath isoprene concentrations in the different samples from each patient, and levels were almost stable within the normal range of healthy controls. Conclusion These results show that CAPD, unlike hemodialysis, has little or no effect on isoprene and isoprenoid-related lipid turnover. This lack of increased endogenous isoprene synthesis, in addition to being a distinctive metabolic feature of CAPD, could have important pathophysiological and clinical implications.
Efficacy of a Low-Dose Intravenous Iron Sucrose Regimen in Peritoneal Dialysis Patients
Authors: Dittrich Elisabeth , Schillinger Martin , Sunder–Plassmann Gere , Hörl Walter H. , Vychytil Andreas 
Published: February 2020

Objective Sufficient iron substitution leads to a decrease in the required recombinant human erythropoietin (rHuEPO) dose and/or an increased hematocrit in dialysis patients. Intravenous (IV) application of larger doses of iron sucrose may be associated with hyperferritinemia, appearance of catalytically free iron, and impaired phagocyte function. Therefore, we investigated the effectiveness of a low-dose IV iron regimen in peritoneal dialysis (PD) patients. Patients and Interventions Forty-five PD patients were followed over a period of 1 year. Serum ferritin, serum transferrin saturation, and hemoglobin were measured monthly. In cases of absolute iron deficiency (serum ferritin < 100 μg/L), 50 mg iron sucrose was given IV every second week. In cases of functional iron deficiency (ferritin ≥ 100 μg/L and transferrin saturation < 20%) and in iron repleted patients (ferritin ≥ 100 μg/L and transferrin saturation ≥ 20%), 50 mg IV iron sucrose was applied monthly. Iron therapy was stopped in cases of acute infection (until complete recovery) and when serum ferritin level was ≥ 600 μg/L. Results To analyze the influence of iron substitution on erythropoiesis and rHuEPO requirements, the EPO resistance index (ERI; quotient of rHuEPO dose in units/kilogram/week and hemoglobin in grams per deciliter) was calculated every 3 months. The ERI decreased significantly during the course of the study in the whole patient group ( p = 0.009) as well as in the subgroup of 21 patients with absolute iron deficiency ( p = 0.01). A nonsignificant decrease in the ERI was observed within the group of 14 iron repleted patients ( p = 0.5). There was no significant change in the ERI in 10 patients with functional iron deficiency ( p = 0.6). Conclusion The low-dose IV iron regimen used in this study substantially decreased rHuEPO requirements in patients with absolute iron deficiency and was effective in maintaining iron stores in iron repleted patients. However, in the absence of significant hyperparathyroidism, aluminum toxicity, or inadequate dialysis, it did not improve the ERI in patients with functional iron deficiency.
Changes in Peritoneal Coagulation and Fibrinolysis after Discontinuation of Chronic Peritoneal Dialysis
Authors: Homma Sumiko , Masunaga Yoshinori , Kurosu Megumi , Inoue Makoto , Sakurai Toshihiro , Asano Yasushi 
Published: February 2020

♦ Objectives To study changes in peritoneal function after transfer from chronic peritoneal dialysis (CPD) to hemodialysis (HD), especially the effects on peritoneal coagulation, fibrinolytic markers, and mesothelium. ♦ Design Prospective observational study. ♦ Setting A tertiary-care university hospital. ♦ Patients Nine patients who transferred from CPD to HD were enrolled in the study after giving fully informed consent. ♦ Methods After transfer to HD, the peritoneal cavity was lavaged with low glucose PD solution once per day through PD catheters left in place. Thrombin–antithrombin III complex (TAT) was measured serially as a marker of peritoneal coagulation. As fibrinolytic markers, fibrinogen/fibrin degradation products (FDP) and plasmin–α2-antiplasmin complex (PIC) were assessed. Cancer antigen 125 (CA125) was measured as a marker of mesothelial cell mass. ♦ Results Levels of peritoneal TAT and FDP were much higher than plasma levels, indicating high local fibrin turnover. Transfer to HD induced a significant fall in mean peritoneal TAT, from 115.8 ± 52.1 to 60.7 ± 21.8 ng/mL, p < 0.05. Except for 1 patient with a 20-fold increase, mean peritoneal FDP decreased significantly, from 43.6 ± 11.1 to 19.6 ± 3.5 μg/mL, p < 0.05. Mean peritoneal PIC increased significantly, from 1.9 ± 0.4 to 3.9 ± 0.6 μg/mL, p < 0.05. Peritoneal CA125 increased from 156.4 ± 57.3 to 1426.2 ± 389.4 U/mL, p < 0.05. ♦ Conclusions Peritoneal fibrin turnover was accelerated on CPD and stabilized after transfer to HD. Transfer to HD also induced mesothelial regeneration.
Peritoneal Dialysis Retardation of Progression of Advanced Renal Failure
Authors: Berlanga Jose Ramon , Marrón Belen , Reyero Ana , Caramelo Carlos , Ortiz Alberto 
Published: February 2020

♦ Objectives The rate of decline of residual renal function is slower in peritoneal dialysis (PD) than in hemodialysis. However, it is unclear which and whether either of the two techniques modifies the natural course of renal failure. We tested whether PD influences the natural course of the progression of chronic renal failure in humans. ♦ Design Retrospective review of clinical charts. ♦ Setting Tertiary-care center. ♦ Patients Fourteen patients were selected from the 36 patients that were treated with PD in our center from January 1997 to June 2000, applying the following criteria: predialysis follow-up longer than 12 months, renal creatinine clearance 20 mL/minute or more at the start of predialysis follow-up, follow-up while on PD longer than 6 months, and renal creatinine clearance above 0 mL/minute at the start of PD. ♦ Main Outcome Measure Residual renal function calculated as renal creatinine clearance obtained from 24-hour urine samples. ♦ Results A lower mean rate of decline of residual renal function was observed during PD than during the predialysis period (–0.06 ± 0.16 vs –0.94 ± 0.74 mL/min/month, p < 0.0005). The rate of decline in renal creatinine clearance was faster in every patient during the predialysis period than during his or her time on PD. ♦ Conclusions These preliminary data support the hypothesis that PD may contribute to the slowing of the natural progression of renal disease in humans, as it does in rodents. Prospective studies involving a larger number of patients are needed to settle the question.
Comparison of the Radioiodinated Serum Albumin (RISA) Dilution Technique with Direct Volumetric Measurements in Animal Models of Peritoneal Dialysis
Authors: Biesen Van Wim , Devriese An S. , Carlsson Ola , Landschoot Van Mike , Dheuvaert Tomy , Lameire Norbert H. 
Published: February 2020

Background Rat models of peritoneal dialysis (PD) are useful for studying the physiology of peritoneal transport and evaluating new osmotic agents. Intraperitoneal (IP) solute concentrations and their evolution over time are easy to measure, but IP volume (IPV) is not. Direct volumetric measurements are the “gold standard,” but they are expensive and do not allow for repetitive measurements in the same animal. The indicator dilution technique is therefore used as an alternative. However, that technique is based on assumptions that are not always valid. The present study compares direct volume measurement with the indicator dilution technique [radioiodinated serum albumin (RISA)] to determine the IPV over time curves in a rat model of PD. Methods In series 1, 17 Sprague–Dawley rats were instilled IP with 25 mL 1.36% glucose dialysate through a Teflon catheter. In 9 animals, 0.35 mL dialysate was sampled and discarded at time points 0, 3, 15, 30, 60, 180, and 240 minutes. In the other 8 animals, no sampling was performed. At 240 minutes, all 12 animals were humanely killed, and direct volumetric measurements of IPV were performed. In series 2, rats were instilled IP with 25 mL 1.36% glucose dialysate containing 18.5 kBq 131I RISA. In 9 animals, dialysate was sampled at 0, 3, 15, 30, 60, 90, 120, 180, and 240 minutes for the construction of the RISA concentration-over-time curve, and to calculate the elimination constant Ke. At 30, 60, 180, and 240 minutes, dialysate was sampled in 6 different animals (total n = 24) to calculate IPV using the RISA dilution technique. Immediately afterward, the animals were humanely killed, and direct volumetric measurements of IPV were performed. Results In series 1, after 240 minutes’ dwell time, the IPV was lower in the sampled animals as compared with the non sampled animals (27.11 ± 1.85 mL vs 30.75 ± 0.59 mL, p = 0.001). In series 2, the evolution of RISA activity in the dialysate over time was described by piecewise linear regression, yielding 3288 – 8.2T counts (cts) for T < 52.72 minutes and 2973 – 1.99T counts for T > 52.72 minutes. The IPV was better predicted with a Ke that took into account the disappearance of RISA by sampling than with a Ke that took into account disappearance of RISA only by absorption. Conclusions If indicator dilution techniques are used to measure IPV, attention must be paid to the disappearance of the osmotic agent and the marker by multiple sampling. The best way to meet that goal is to use micropipettes to avoid large sample volumes.