Continuous Ambulatory Peritoneal Dialysis Fluids Research Articles

Microbial Profile, Peritoneal Fluid White Blood Cell Count, and Outcome of Peritoneal Dialysis-Related Peritonitis at Indonesian Tertiary Hospital.

Peritonitis caused by peritoneal dialysis (PD) remains a common complication of continuous ambulatory PD (CAPD). The purpose of this study is to determine the microbial profile in CAPD-related peritonitis, the optimal cutoff of white blood cell (WBC) count, and the percentage of polymorphonuclear (PMN) in CAPD fluid in the prediction of CAPD-related peritonitis, together with the outcome of CAPD-related peritonitis at an Indonesian tertiary hospital. This is a retrospective cohort study of CAPD-related peritonitis patients at Indonesian tertiary hospitals from November 2020 to October 2022. Patients with suspected CAPD-related peritonitis who were tested for CAPD fluid culture and WBC count in CAPD fluid were eligible for this study. Patient's diagnosis and outcome obtained from medical records. Differences in clinical outcomes by category of microorganisms were analyzed with Fisher exact test. The Mann-Whitney test and receiver operating characteristic curve were used to determine optimal WBC and PMN cutoff. This study included 58 patients and 102 episodes of CAPD-related peritonitis. CAPD-related peritonitis was caused by 29.4% Gram-negative bacteria, 21.5% Gram-positive bacteria, 7.8% fungi, and 6.9% polymicrobial bacteria. CAPD fluid WBC count >79 cells/μL and PMN percentage >50% had a sensitivity of 76.4% and a specificity of 92.9% in predicting CAPD-related peritonitis. There was a significant difference in outcome between Gram-negative and Gram-positive bacterial peritonitis. It is critical to understand the microbial profile in CAPD-related peritonitis. Lower WBC count cutoff points in CAPD fluids may improve sensitivity in predicting CAPD-related peritonitis.

Performance evaluation of UF-4000 body fluid mode for detection of bacteria in body fluids

BackgroundMicrobiological analysis of body fluids (BF) provides important information for diagnosis of infection. We evaluated the analytical performance of bacterial count by UF-4000 BF mode for ascitic, cerebrospinal, pleural, synovial and continuous ambulatory peritoneal dialysis fluids compared to classical microbiological procedure (direct Gram staining and culture). Materials and methodsFor the 1,734 BF analyzed, distribution of UF-4000 bacterial count was analyzed according to the level of growth culture and results were compared using Mann-Whitney test. ROC curves analysis allowed to define the best cut-off value to predict or exclude positive culture for each type of BF. ResultsUF-4000 bacterial counts were significantly lower in sterile than in infected BFs (p < 0.00001) and correlated with the level of growth on culture. The ROC curves of bacteria/μL and culture positivity yielded area under the curve >0.80 for each type of BF. Optimal cut-offs were chosen with excellent statistical parameters (sensitivity ranging from 0.70 to 0.86, specificity from 0.78 to 0.98, negative predictive value >0.95 and Youden index >0.55). ConclusionFor BF, UF-4000 bacterial count correlate with culture results and is a discriminative method enhancing detection of microbiological etiology. It could be used as a screening method based on the cut-off values proposed in this study.

Performance evaluation of UF-4000 body fluid mode for automated body fluid cell counting

BackgroundCytological analysis of body fluids (BF) provides important information for diagnosis in various medical conditions. We evaluated the analytical performance of the UF-4000 BF mode for ascitic, cerebrospinal, pleural, synovial and continuous ambulatory peritoneal dialysis fluids compared to light microscopy counting (LM). Materials and methods223 consecutive BF were analyzed by UF-4000 and results were compared using Pearson’s correlation, Bland-Altman analysis, and contingence tests at relevant cut-off values. This study also included the evaluation of precision, linearity, and carryover. ResultsFor white and red blood cells (WBC, RBC) counts in all BF, correlation was excellent with Pearson’s coefficients R2 > 0,98. Bland-Altman analysis didn’t reveal significant differences with limited bias for WBC ranging from −10 to −1 WBC/µL and bias ranging from −43 to −6/µL for RBC. At specific cut-off values for WBC, Se and Spe were 100% except for ascites (Spe = 98%) due to two false positive.Precision evaluated at three concentration levels was good for each parameter (WBC < 10%). Linearity was excellent for WBC (R2 > 0,99) and carryover negligible (<0,004%). ConclusionUF-4000 BF mode is a good alternative to manual LM for BF cell counting. This automated method gives rapid and accurate results which is important for therapeutic decisions.

Performance of Abbott Alinity hq hematology analyzer for automated cell counting of body fluids.

Body fluid cell counting and differentiation provide essential information for diagnosis and monitoring of diverse pathologies. We evaluated the performance of the newly launched Abbott Alinity hq hematology analyzer for automated cell counting in body fluids and compared red blood cell (RBC) and total nucleated cell (TNC) counts with the Cell-Dyn Sapphire automated hematology analyzer. Differential counts were compared with microscopic differentiation on cytocentrifuged preparations. Background concentration limits, limit of detection (LOD), linearity, imprecision, functional sensitivity and carryover were evaluated. For method comparison, we collected 172 body fluids (17 continuous ambulatory peritoneal dialysis fluids, 56 cerebrospinal fluids and 99 serous fluids). Background concentration limits were ≤1000 cells/μL for RBC counts and ≤3 cells/μL for TNC counts. The LOD was 1000 RBC/µL and 5 TNC/µL. Results from linear regression analysis revealed excellent linearity. Functional sensitivity was 3000 cells/µL for RBC counts and 50 cells/µL for TNC counts. Carryover was 0.6% and 0.1% for TNC and RBC, respectively. The Alinity hq shows good clinical performance. We demonstrated comparable performance for body fluid cell counting between the Alinity hq analyzer and the Cell-Dyn Sapphire. The Alinity hq can be very useful as a screening tool for body fluid cell counting.

Continuous ambulatory peritoneal dialysis, ascitic and pleural body fluids evaluation with the Mindray BC-6800 hematology analyzer.

Accurate evaluation of hematology analyzers is recommended before these devices can be broadly introduced for the routine testing of continuous ambulatory peritoneal dialysis (CAPD), ascitic, and pleural fluids. We evaluated the performance of Mindray BC-6800 for white blood cell (WBC) and differential cell count in 50 CAPD, 60 ascitic and 40 pleural compared with manual microscopy. Within-run precision, limit of blank (LoB), limit of detection (LoD), limit of quantitation (LoQ), and carryover were assessed. The Passing-Bablok regression in all fluids showed the following equations: yWBC =1.05x+3.31 (95%CI slope 0.95 to 1.12; intercept -0.25 to 5.52); yMN =0.85x+15.63 (95%CI slope 0.72 to 1.05; intercept -24.18 to 84.47); and yPMN =1.21x+13.37 (95%CI slope 1.03 to 1.35; intercept 4.00 to 32.47) with bias 78 cells/μL. The AUC for clinical PMN cut-off was 0.88 (95%CI: 0.77 to 0.98). In ascitic, pleural, and CAPD fluids the AUC for clinical PMN cut-off were 0.88 (95%CI: 0.63 to 1.00), 0.83 (95%CI: 0.68 to 0.99), and 1.00 (95%CI: 1.00 to 1.00) respectively. CV ranged from 3%-34%. LoB of 3cell/μL was verified. LoD and LoQ reported the same result (8cells/μL). Carry over never exceeded 0.05%. The effectiveness of BC-6800 to categorize cells from different body fluids was not compromised by the slight positive bias observed. This conclusion is supported by the high AUC and agreement between the automated method and the reference method. The results show that BC-6800 offers rapid, accurate, and reproducible results for clinical management of CAPD, ascitic, and pleural fluids.

Continuous ambulatory peritoneal dialysis: perspectives on patient selection in low- to middle-income countries.

Chronic kidney disease is a major public health problem that continues to show an unrelenting global increase in prevalence. The prevalence of chronic kidney disease has been predicted to grow the fastest in low- to middle-income countries (LMICs). There is evidence that people living in LMICs have the highest need for renal replacement therapy (RRT) despite the lowest access to various modalities of treatment. As continuous ambulatory peritoneal dialysis (CAPD) does not require advanced technologies, much infrastructure, or need for dialysis staff support, it should be an ideal form of RRT in LMICs, particularly for those living in remote areas. However, CAPD is scarcely available in many LMICs, and even where available, there are several hurdles to be confronted regarding patient selection for this modality. High cost of CAPD due to unavailability of fluids, low patient education and motivation, low remuneration for nephrologists, lack of expertise/experience for catheter insertion and management of complications, presence of associated comorbid diseases, and various socio-demographic factors contribute significantly toward reduced patient selection for CAPD. Cost of CAPD fluids seems to be a major constraint given that many countries do not have the capacity to manufacture fluids but instead rely heavily on fluids imported from developed countries. There is need to invest in fluid manufacturing (either nationally or regionally) in LMICs to improve uptake of patients treated with CAPD. Workforce training and retraining will be necessary to ensure that there is coordination of CAPD programs and increase the use of protocols designed to improve CAPD outcomes such as insertion of catheters, treatment of peritonitis, and treatment of complications associated with CAPD. Training of nephrology workforce in CAPD will increase workforce experience and make CAPD a more acceptable RRT modality with improved outcomes.

Evaluation of different culture methods for the diagnosis of peritonitis in patients on continuous ambulatory peritoneal dialysis

A total of 170 continuous ambulatory peritoneal dialysis (CAPD) fluids were processed by various culture methods, including direct inoculation of the centrifuged sediment, inoculation into automated blood culture bottles, water lysis, Tween-80 incorporated blood agar, and Triton-X treatment of the specimen. Of 170 CAPD fluids, 127 showed the growth of bacteria/fungi. Sixty-three fluids showed growth by all methods, the water lysis alone detected 24 additional positive cultures, while Tween-80 blood agar and Triton-X yielded 30 additional positive cultures. A combination of water lysis, Tween-80 blood agar and Triton-X treatment of the CAPD fluid is recommended for diagnosis of CAPD peritonitis in resource-limited settings.

Hypertonic glucose-based peritoneal dialysate is associated with higher blood pressure and adverse haemodynamics as compared with icodextrin

Little is known about the haemodynamic effects of continuous ambulatory peritoneal dialysis (CAPD) despite its widespread use in the management of end-stage renal failure. We undertook a study to delineate the haemodynamic effects of CAPD using glucose-containing fluids (1.36 and 3.86% glucose) and icodextrin. Eight CAPD patients were recruited for a prospective crossover study. Patients attended for two investigatory days (in random order). CAPD was carried out using 1.36% followed by 3.86% glucose (buffered with lactate/bicarbonate, Physioneal) on one study day and 1.36% glucose followed by 7.5% icodextrin (Extraneal) on the other day. Dwell times were 150 min. Blood pressure (BP) and a full range of haemodynamic variables including pulse (HR), stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR) were measured non-invasively using continuous arterial pulse wave analysis. BP was significantly higher during 3.86% glucose dwells as compared with 1.36% glucose or icodextrin dwells (P<0.0001). TPR during all three dwells was similar; the higher blood pressure was due to an increased HR, SV and, therefore, CO during 3.86% glucose dwells. The higher blood pressure during the 3.86% glucose dwells was present despite the highest ultrafiltration volume and sodium removal. This study demonstrates large magnitude haemodynamic changes in response to CAPD. In addition to the well-recognized adverse effects on blood glucose and long-term peritoneal membrane viability, CAPD fluids containing high glucose concentrations may also exert undesirable effects on systemic haemodynamics, with potential long-term consequences for patient outcomes.

Catheter-related bacteremia due to Kocuria rosea in a patient undergoing peripheral blood stem cell transplantation

BackgroundMicrococcus species may cause intracranial abscesses, meningitis, pneumonia, and septic arthritis in immunosuppressed or immunocompetent hosts. In addition, strains identified as Micrococcus spp. have been reported recently in infections associated with indwelling intravenous lines, continuous ambulatory peritoneal dialysis fluids, ventricular shunts and prosthetic valves.Case presentationWe report on the first case of a catheter-related bacteremia caused by Kocuria rosea, a gram-positive microorganism belonging to the family Micrococcaceae, in a 39-year-old man undergoing peripheral blood stem cell transplantation due to relapsed Hodgkin disease. This uncommon pathogen may cause opportunistic infections in immunocompromised patients.ConclusionsThis report presents a case of Kocuria rosea catheter related bacteremia after stem cell transplantation successfully treated with vancomycin and by catheter removal.

Specific characteristics of peritoneal leucocyte populations during sterile peritonitis associated with icodextrin CAPD fluids.

Icodextrin dialysate used for peritoneal dialysis contains an iso-molar glucose polymer solution, which provides sustained ultrafiltration over long dwell times and is considered a valuable approach to reduce intraperitoneal glucose exposure. However, several side effects have been described, including abdominal pain and allergic and hypersensitivity reactions. Also, reactions compatible with chemical peritonitis have been reported. Over the period of a few months (January 2002-May 2002), a remarkable increase in the number of continuous ambulatory peritoneal dialysis (CAPD) patients using icodextrin dialysate diagnosed with sterile peritonitis was observed in our unit. Five of the CAPD patients using icodextrin dialysate in our unit and diagnosed with sterile peritonitis were screened for leucocyte count and leucocyte differentiation during a follow-up period of 77 +/- 23 days. In addition, expression of CD14, a receptor for lipopolysaccharide (LPS), on the peripheral and peritoneal monocyte population was analysed. These results were compared to CAPD patients suffering from bacterial peritonitis. The peritoneal leucocyte count of CAPD patients using icodextrin dialysate and diagnosed with sterile peritonitis did not decrease significantly before treatment with icodextrin dialysate was interrupted, whereas it currently disappeared within 2-4 days in proven bacterial peritonitis. The sterile, cloudy icodextrin effluent contained an excess of macrophages on the day of diagnosis, whereas in bacterial peritonitis essentially an increase in the granulocyte population was observed. No elevation in the eosinophil population was observed. In contrast to bacterial peritonitis, we observed no increase in CD14 expression on the peripheral and peritoneal macrophages on the day of presentation and during the follow-up period. Specific batches of the icodextrin CAPD fluids contain a macrophage chemotactic agent, which causes a sustained inflammatory state in the peritoneal cavity. Because no increase in the expression of the LPS receptor CD14 could be observed, the increased peritoneal leucocyte count is probably not caused by LPS or LPS-like (possibly peptidoglycan-like) contamination.

Total metal concentrations in serum of dialysis patients and fractionation of Cu, Rb, Al, Fe and Zn in spent continuous ambulatory peritoneal dialysis fluids

Total metal concentrations were determined in the serum of 12 continuous ambulatory peritoneal dialysis (CAPD) patients and in fresh and spent CAPD fluids by electrothermal and flame atomic absorption spectrometry (ETAAS, FAAS). Concentrations of Cu in serum of CAPD patients ranged from 720 to 1780 ng cm −3, Rb from 128 to 346 ng cm −3, Al from 10 to 72 ng cm −3, Fe from 800 to 2300 ng cm −3 and Zn from 659 to 1310 ng cm −3. The accuracy of the analytical procedure was checked by the analysis of the reference material Seronom™, Trace Elements in Serum. Good agreement between the certified and determined values was obtained for Al, Cu, Fe and Zn. The data on the total metal concentrations in CAPD fluids indicated that during CAPD fluid exchange the losses of Cu from 5.0 to 35 ng cm −3, of Rb from 50 to 110 ng cm −3 and of Al from 3.0 to 14.0 ng cm −3 occurred through the peritoneal membrane. Although fresh CAPD fluids contained traces of Fe (3.0–5.0 ng cm −3), the transfer of this element took place through the peritoneal membrane into spent CAPD fluid (13.0–38.0 ng cm −3). Zn concentrations were in general lower in spent (20.0–80 ng cm −3) than in fresh CAPD fluids (∼100 ng cm −3). To follow the mechanisms of the transfer of trace elements through the peritoneal membrane of CAPD patients, fractionation of metals was carried out in spent CAPD fluids by size exclusion chromatography with UV and AAS detection, applying Superdex HR 10/30 column. The chromatographic run was followed at 278 nm and separated metal species also determined ‘off line’ in 1 cm 3 fractions by ETAAS or FAAS. From the UV chromatograms and AAS analysis of trace elements in the separated fractions it was demonstrated that Cu, Al, Fe and Zn were bound to proteins and only partially to low molecular weight (LMW) species, while Rb was associated exclusively with LMW species. For characterisation of the high molecular weight (HMW) binding proteins, fractions containing trace elements were subjected to SDS-PAGE electrophoresis. Al and Fe were presumably bound to transferrin, but due to its low concentration in spent CAPD fluids, it was not possible to confirm its presence in the separated fractions. About 10% of Al and 15% of Fe corresponded to LMW species. A fraction of HMW proteins of Cu in spent CAPD fluids was most probably bound to albumin and Zn to albumin and globulins. About 50% of Cu and Zn existed in LMW proteins, while Zn was also found partially in ionic form.

Assessment of the FAN anaerobic bottle for culture of continuous ambulatory peritoneal dialysis fluid using the BacT/Alert system

The purpose of this study was to determine if the newly available FAN anaerobic bottle (FANAN) alone would be comparable to the combination of the FAN aerobic (FANAE) plus the standard BacT/Alert anaerobic (REGAN) bottles for culture of continuous ambulatory peritoneal dialysis (CAPD) fluid from patients with CAPD peritonitis. CAPD fluid (10 mL) was injected into each bottle, which was then monitored by the BacT/Alert instrument by using a 7-day protocol. Aerobic and anaerobic terminal subculture were performed on all bottles before they were classified as being culture negative. There were 181 effluents received that were suitable for analysis. Growth was detected in 76 (42%) effluents by at least one method. FANAE was the single best medium detecting 84/96 (88%) of all organisms whereas the FANAN and REGAN each detected 69/96 (72%). The combination of FANAE and REGAN bottles detected 92/96 (96%) isolates, which was significantly better than the FANAN or FANAE alone for isolate recovery ( p < 0.001). The isolates that were missed by the FANAN but that were recovered by either FANAE or REGAN were all facultative anaerobes commonly detected in CAPD fluids. Terminal subculture revealed otherwise undetected pathogens in 3.9% of positive effluents, usually Pseudomonas aeruginosa. Based on our data, FANAE was the single best bottle for detection of CAPD peritonitis and, in combination with an anaerobic bottle, detected growth from the most effluents. FANAN alone could not substitute for the FANAE/REGAN combination. Although terminal subculture remains controversial, we recommend routine aerobic subculture to ensure that no P. aeruginosa isolates are missed.

Optimisation of parameters for determination of rubidium in spent CAPD fluids by flame and electrothermal atomic absorption spectrometry

An analytical procedure is reported for the determination of rubidium in spent continuous ambulatory peritoneal dialysis (CAPD) fluids by flame and electrothermal atomic absorption spectrometry (FAAS, ETAAS). Samples of spent CAPD fluids were collected as 5 ml aliquots in polyethylene tubes and stored in a freezer at −20°C. Before analysis, samples were equilibrated to room temperature and analysed within 8 h. A total of 2 mg ml −1 of caesium was added to each sample and standard solution to overcome interferences from ionisation. An air–acetylene flame was applied in FAAS determinations. Analysis was performed against aqueous standards. The calibration graph was linear from 30.0 up to 5000 μg l −1 Rb, while the limit of detection (3 s) was found to be 20.0 μg l −1 rubidium. Good repeatability of measurement (RSD 1%) was obtained. Parameters were also optimised for determination of rubidium in spent CAPD fluids by ETAAS. Ten-fold diluted samples (3.5% nitric acid) were analysed applying standard addition calibration. The calibration graph was linear from 2.0 up to 30.0 μg l −1 rubidium, while the limit of detection (3 s) was found to be 1.0 μg l −1 rubidium (sample volume 10 μl). Good repeatability of measurement (RSD 5%) was obtained. The results of direct determination by FAAS and ETAAS were compared to those obtained after acid digestion of samples in Parr bombs. The accuracy of the procedure for direct determination was checked by spiking samples. In 73% of samples analysed, the differences between the results obtained by the two techniques, either for direct determinations of samples or for samples digested in a Parr bomb did not exceed ±10%.

Problems related to determination of trace elements in spent continuous ambulatory peritoneal dialysis fluids by electrothermal atomic absorption spectrometry

Critical parameters which influence the direct determination of trace elements in spent continuous ambulatory peritoneal dialysis (CAPD) fluids by electrothermal atomic absorption spectrometry (ETAAS) were investigated. Samples were collected after CAPD fluid exchange in 5.0 ml polyethylene cups and stored at −20°C. Daily spent CAPD fluids were frozen immediately, while nightly spent CAPD fluids were frozen 2–3 h after the morning exchange. Before analysis samples were equilibrated to room temperature and analysed within 8 h. It was found experimentally that some samples which were not frozen immediately leaked out of the pyrolytically coated graphite tube before the drying step. In order to keep the sample in the graphite tube and to obtain reproducible measurements of copper, aluminium and iron, samples were diluted before analysis 1+1 with 32% v/v nitric acid. The standard addition method was used in the calibration procedure. The results of direct ETAAS determinations for copper agreed well (±5–10%) with those obtained after acid digestion of CAPD fluids in Parr bomb. The procedure for direct determination of all three elements was validated with spiked samples.

Disadvantage of long-term CAPD for preserving cardiac performance: An echocardiographic study

The indices of cardiac performances were compared between 31 continuous ambulatory peritoneal dialysis (CAPD) and 20 long-term hemodialysis (HD) patients. They were subdivided into three groups according to dialysis duration: L-CAPD (n = 16, mean age and CAPD duration were, respectively, 53 +/- 8 [SD] years and 77 +/- 13 months); S-CAPD (n = 15; 52 +/- 12 years, 28 +/- 12 months); HD (n = 20; 51 +/- 10 years, 162 +/- 52 months). The diabetic HD patients (DM-HD; n = 13; 60 +/- 13 years of age, 22 +/- 11 months) were chosen separately. Thirteen normotensive subjects with normal kidney function (mean age, 57 +/- 9 years) were selected as an age-matched control group. There were no significant differences between groups in age, gender, incidence of original kidney disease, or serum biochemical data. The blood pressure and the cardiothoracic ratio in L-CAPD were highest among groups. The indices of left ventricular (LV) hypertrophy as well as LV performance by means of echocardiography or pulsed Doppler were compared. Among nondiabetic dialysis patients, the calculated LV mass index (LVMI) of 166.4 +/- 84.3 g/m2 and the ratio of the peak atrial filling velocity to the peak diastolic flow velocity of 1.25 +/- 0.4 in L-CAPD were greatest, and the left ventricular fractional shortening (%FS) of 34.2 +/- 10.8% in L-CAPD was smallest. LVMI or %FS of L-CAPD was the same as DM-HD of 161.0 +/- 40.7 g/m2 or 31.6 +/- 8.2%. Possibly, poor control of hypervolemia, which is caused by peritoneal problems induced by either peritonitis or chronic exposure to high-glucose dialysate, causes a substantial cardiac preload leading to incipient cardiac failure in L-CAPD. According to the similar results of L-CAPD and DM- HD, it may be that hypertension, hyperlipidemia, or long-term constant glucose loading of CAPD fluids in addition to impaired glucose tolerance by chronic renal failure is more or less related to the progression of LV hypertrophy and latent cardiac dysfunction in long- term CAPD patients. In this context, CAPD of more than 5 years' duration is disadvantageous for preserving cardiac function as compared with HD. (Am J Kidney Dis 1998 Sep;32(3):482-7)

Biocontainers and Water Quality for Continuous Ambulatory Peritoneal Dialysis Fluids

Biocontainers and Water Quality for Continuous Ambulatory Peritoneal Dialysis Fluids

Bicarbonate versus Lactate-Based Capd Fluids: A Biocompatibility Study in Rabbits

Previous in vitro biocompatibility studies have shown bicarbonate-based continuous ambulatory peritoneal dialysis (CAPD) fluids to be superior to those based upon lactate/acetate. To evaluate these findings in vivo, 41 rabbits were subjected to CAPD for four weeks in a randomized prospective study using either Dianeal, a commercially available dialysis fluid containing lactate, or 87b, a bicarbonate-based CAPD fluid. Ten rabbits with CAPD catheters, which were flushed with a heparin solution every 36 hours, served as controls. None of the control rabbits showed clinical or histopathological signs of peritonitis, while 8 of 20 in the Dianeal group and 6 of 21 in the 87b group contracted peritonitis. Four rabbits in the Dianeal group had to be sacrificed early due to severe peritonitis. Post mortem examinations, including scanning and light microscopy, did not reveal any macroscopic or microscopic differences among the three groups of noninfected animals. No significant distinctions between the groups could be made for body temperature, weight gain, dialysate volume, dialysate differential leukocyte count, dialysate protein content, and food intake during the course of the study. In conclusion, the present animal model did not reveal any major difference in the biocompatibility between the lactate- and the bicarbonate-based CAPD fluids.

Stability of Amphotericin B in CAPD Fluid

Amphotericin B is the drug of choice in continuous ambulatory peritoneal dialysis (CAPD) associated fungal peritonitis and is usually administered intraperitoneally. The drug is stated to be incompatible with anions. All CAPD fluids contain chloride and lactate anions. Therefore, the physical and chemical compatibility of amphotericin B with dextrose 5%, Dianeal 1.36% CAPD fluid, and Dianeal 1.36% peritoneal effluent was studied at amphotericin B concentrations of 1, 2, and 5 mg/L. Amphotericin B was most stable in Dianeal CAPD fluid. The rate of degradation was concentration dependent in dextrose 5% and peritoneal effluent. The higher the concentration, the lower the rate of degradation. After an incubation of 6 h at 37 degrees C, no significant decomposition was found at all concentrations studied in Dianeal CAPD fluid whereas 12-18% decomposition was found in effluent. No physical incompatibility with any solution was observed.

Dialysis fluids and local host resistance in patients on continuous ambulatory peritoneal dialysis.

The ability of polymorphonuclear leukocytes, monocytes and peritoneal macrophages to mount a respiratory burst in continuous ambulatory peritoneal dialysis (CAPD) fluids was tested in a phorbol-myristate acetate stimulated chemiluminescence assay. Fresh CAPD fluids depressed the chemiluminescence response of all three types of phagocytes tested to less than 18% of their chemiluminescence response in control buffer. When tested in spent CAPD fluids the suppression of chemiluminescence was 30-32%. Oxygen consumption of polymorphonuclear leukocytes was depressed in fresh CAPD fluids to below 40%. Both phagocytosis of Escherichia coli by and bactericidal capacity of polymorphonuclear leukocytes and monocytes were suppressed in fresh CAPD fluids but not in spent effluents. The influence of acidic pH and hyperosmolality on phagocytic functions were studied separately by modifying the acidity or the glucose content of the control buffer. pH values below 6.0 significantly inhibited chemiluminescence but not phagocytosis. Under hypertonic conditions, both phagocytosis and chemiluminescence were inhibited. We conclude that the currently available CAPD solutions are beyond the limits of acid and osmotic tolerance of human phagocytic cells, and may thus compromise the peritoneal defenses of CAPD patients.

Exposure of patients to phthalates from polyvinyl chloride tubes and bags during dialysis.

The exposure of patients to the plasticizer di-(2-ethylhexyl)phthalate (DEHP) from polyvinyl chloride (PVC) tubes and bags during dialysis has been investigated. In vitro studies of the migration of DEHP from hemodialysis tubes into plasma revealed a migration coefficient of 7.7 micrograms/ml/h. An artificial kidney did not influence the plasma concentration of DEHP. The calculated exposure from a single hemodialysis can be as much as the total annual exposure using continuous ambulatory peritoneal dialysis (CAPD). CAPD fluids in PVC bags contain low concentrations of DEHP and its hydrolysis product mono-(2-ethylhexyl)phthalate (MEHP). These phthalates were analyzed in serum from patients receiving both CAPD and hemodialysis using gas chromatography. A group of patients not yet on dialysis treatment was used as control. In no case could MEHP be detected. The DEHP concentration was 0.8-4.2 micrograms/ml serum in the 17 hemodialysis patients after dialysis and 0.1-0.9 microgram/ml in 4 of the CAPD patients. In 3 of the CAPD and all of the predialysis patients, DEHP could not be detected (less than 0.1 microgram/ml).