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R T Krediet

Publications and source records attributed to R T Krediet.

At least 19 recordsLinked to original sources
PubMed1996

Peritoneal transport characteristics with glucose polymer based dialysate.

Dialysate fluids containing glucose polymers as osmotic agent are different from the conventional solutions, because they are iso-osmotic to plasma and produce transcapillary ultrafiltration (TCUF) by colloid osmosis. To investigate the effects on fluid and solute kinetics, a comparison was made between a 7.5% glucose polymer based dialysate (icodextrin) and 1.36% and 3.86% glucose based dialysate in 10 stable CAPD patients. In each patient three standard peritoneal permeability analyses (SPA) were done with the osmotic agents and concentrations mentioned above. Dextran 70 was added to the glucose solutions to calculate fluid kinetics. In the glucose polymer SPAs fluid kinetics were calculated from the dilution and disappearance of dextrin. The TCUF rate with icodextrin was closer to that obtained with 3.86% glucose than to 1.36% glucose. Extrapolation of the fluid profiles revealed sustained ultrafiltration with icodextrin. TCUF increased linearly in time in the icodextrin tests, whereas a hyperbola best described the glucose profiles. The effective lymphatic absorption rate with icodextrin was similar to the glucose based solutions. Mass transfer area coefficients of low molecular weight solutes with icodextrin were also similar to the values obtained with glucose, as was D/P creatinine. A positive correlation was present between the MTAC creatinine and the TCUF rate with icodextrin (r = 0.66, P = 0.05), which was absent in the glucose SPAs. This suggests that in patients with a larger effective peritoneal surface area, more ultrafiltration can be achieved by glucose polymer solutions. Clearances of beta 2-microglobulin (beta 2m) were higher with icodextrin than with 3.86% glucose and 1.36% glucose dialysate (P < 0.05). No differences were found for the larger serum proteins albumin, IgG and alpha 2-macroglobulin. Initial D/PNa-->was higher (0.96) with icodextrin than with the glucose based solutions (0.92), due to the higher Na+ concentration of icodextrin, and it remained unchanged during the dwell. In contrast, D/PNa+ of 1.36% glucose increased during the dwell, whereas D/PNa+ decreased with 3.86% glucose until 60 minutes, followed by a subsequent increase. The ultrafiltration coefficient (UFC) of the total peritoneal membrane was assessed using 3.86% glucose (0.18 +/- 0.04 ml/min/mm Hg), and the UFC of the small pores was assessed using icodextrin (0.06 +/- 0.008 ml/min/mm Hg). The difference between these represented the UFC through the transcellular pores, which averaged 50.5% of the total UFC, but with a very wide range (0 to 85%). An inverse relation existed between the duration of CAPD treatment and the total ultrafiltration coefficient (r = -0.68, P < 0.04), which could be attributed to a lower UFC of the transcellular pores in long-term patients (r = -0.66, P < 0.05), but not to the UFC of the small pores (r = -0.48, NS). The TCUFRo-60 min through the transcellular pores correlated with the sodium gradient, corrected for diffusion, in the first hour of the dwell (r = 0.69, P < 0.04), indicating that both parameters indeed measure transcellular water transport. It can be concluded that the glucose polymer solution induced sustained ultrafiltration and had no effect on peritoneal membrane characteristics. In addition, the results of the present study support the hypothesis that the glucose polymer solutions exerts its osmotic pressure across intercellular pores with radii of about 40 A. This leads to increased clearances of low molecular weight proteins such as beta 2m that are transported through these pores without sieving of Na+. The latter, as found during 3.86% glucose dialysate, is probably caused by transcellular water transport. The transcellular water transport accounted for 50% of the total ultrafiltration with glucose based dialysis solutions. It was lower in long-term CAPD patients.

Adult↗
PubMed1996

Ingestion of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli by human peritoneal mesothelial cells.

In the present study we examined whether mesothelial cells can ingest and digest bacteria. The results showed that all strains were ingested. Ingested staphylococci proliferated abundantly, and only a few were digested. Escherichia coli, however, was digested during the first 8 h, whereafter the mesothelial cells disintegrated and proliferation of bacteria could be observed. The clinical implications of these findings are discussed.

Cells, Cultured↗
PubMed1996

Cytokine patterns in the effluent of continuous ambulatory peritoneal dialysis: relationship to peritoneal permeability.

Cytokines are pluripotent pleiotropic agents that have received widespread attention over the last few years. Not surprisingly, the have also been studied in the context of continuous ambulatory peritoneal dialysis. Cytokines play a central role in this treatment modality for uremic patients, because these inflammatory mediators act upon the biological dialysis membrane, i.e. the peritoneum, while simultaneously they participate in host defense mechanisms. This review describes which cytokines are present in dialysate, whether there is support for intraperitoneal release, and under which circumstances. If focuses particularly on the relationship between cytokines in peritoneal effluent and peritoneal permeability to macromolecules. In addition, the presence of prostanoids in dialysate and their role in the local regulation of peritoneal permeability are discussed, because cyclooxygenase products are tightly linked to cytokine networks.

Animals↗
PubMed1996

Fluid kinetics in CAPD patients during dialysis with a bicarbonate-based hypoosmolar solution.

The magnitude of transcapillary backfiltration by the colloidosmotic pressure within the peritoneal capillaries compared to the effective lymphatic absorption was investigated in continuous ambulatory peritoneal dialysis patients. This was done during a 4-hour dwell period, using a hypoosmolar dialysis fluid (280 mosm/kg H2O) in 8 patients and compared to 5 of these patients using a 1.36% glucose (GS; 324 mosm/kg H2O). The low molecular weight solute transport did not differ between the two solutions. The intraperitoneal dextran 70 concentration increased during the dwell with the hypoosmolar dialysis fluid (from 770 to 945 mg/l; p = 0.000002) and decreased with the GS (from 859 to 719 mg/l; p = 0.007). With the GS the transcapillary ultrafiltration was directed towards the abdominal cavity during the dwell period. With the hypoosmolar fluid, the transcapillary ultrafiltration was continuously directed towards the circulation. In this solution, the magnitude of transcapillary backfiltration due to colloidosmotic pressure within the peritoneal capillaries was 0.4 +/- 0.1 ml/min. In conclusion, intraperitoneal markers can be used in continuous ambulatory peritoneal dialysis patients for determination of effective lymphatic absorption and transcapillary fluid passage in both transport directions.

Adult↗
PubMed1996

Measurement of residual renal function in patients treated with continuous ambulatory peritoneal dialysis.

Renal function contributes markedly to the adequacy of continuous ambulatory peritoneal dialysis (CAPD). The best way to measure it in clinical practice has not been established. Ten stable CAPD patients with residual renal function were investigated to compare the GFR measured as inulin clearance (Cli) with the creatinine clearance (Clc), the urea clearance (Clu), and with 0.5(Clc + Clu). Thereafter, an analysis of whether the administration of cimetidine could improve the accuracy of these clearances was performed. Two clearance periods (CP) of 24 h were investigated. During CP-2, patients received 400 mg cimetidine twice daily, for a total dose of 1200 mg. Two h before the urine and dialysate collection period, inulin was administered iv. Calculations were done for each CP for Cli, Clc, Clu, Clc-Cli, the Clc/Cli ratio, and the tubular secretion of creatinine (TSc). No differences between CP-1 and CP-2 were present for urinary excretion of volume and solutes, and clearance rates of inulin and urea. The median TSc decreased from 0.71 mumol/min (range, -0.24 to 5.90) in CP-1 to 0.30 mumol/min (range, -0.18 to 0.64) in CP-2 (P < 0.05). Therefore, the median ratio of Clc/Cli decreased from 1.23 (range, 0.87 to 2.20) in CP-1 to 1.11 (range, 0.95 to 1.51) in CP-2 (P < 0.05). The median overestimation of the Cli in CP-1 by the Clc was 0.90 mL/min (range, -0.28 to 3.80) and by the 0.5(Clc + Clu) was 0.30 (range, -0.67 to 1.52). The median overestimation of Cli during cimetidine treatment in CP-2 was 0.43 mL/min (range, -0.21 to 1.20). The range, in differences between Cli and Clc, in CP-2 was smaller than that between Cli and 0.5(Clc + Clu) in CP-1. The difference between the clearance rate of inulin and creatinine or the combined clearance rate of urea and creatinine was not influenced by the magnitude of the average GFR. It can be concluded that the administration of cimetidine improved the accuracy of measuring the GFR with the Clc in CAPD patients.

Adult↗
PubMed1996

Effect of electric charge on the transperitoneal transport of plasma proteins during CAPD.

BACKGROUND: Controversy exists as to whether electric charges of plasma proteins influence their transport across the peritoneal membrane during CAPD. Fixed negative charges in the peritoneal membrane are diminished during peritonitis in rats. METHODS: Peritoneal clearances of 10 proteins and their isoforms were used to establish the relationship between peritoneal clearance and molecular weight. The observed protein clearances were compared with the predicted clearances based on molecular weight. Clearances of proteins with different charge but identical size were compared. Stable patients and peritonitis patients were compared. Results. Only the peritoneal clearance of lipase, LDH 4/5 and IgG3 were significantly different from the predicted values (P<=0.05). The peritoneal clearance of slightly anionic beta2 microglobulin (1072 microl/min) and cationic lysozyme (572 microl/min) showed no evidence for charge selectivity; neither did the peritoneal clearance of slightly anionic transferrin (86 microl/min) and highly anionic albumin (99 microl/min). The peritoneal clearance of IgG1, IgG2 and IgG4 were identical (32, 31 and 31 microl/min), despite their different charge. The peritoneal clearance of cationic LDH 4/5 was 137 microl/min and higher than the peritoneal clearance of neutral LDH 3 (97 microl/min, P=0.01) and LDH 1 (59 microl/min, P=0. 02). These results suggested charge selectivity; however in five additional patients during peritonitis the peritoneal clearance of LDH 4/5 increased to 10 times the peritoneal clearance of LDH 1. Local LDH isoenzyme release from the cells present in the dialysate was shown to be responsible in stable and peritonitis patients. Likewise, the higher peritoneal clearance of neutral pancreatic amylase (234 microl/min) compared to anionic salivary amylase (142 microl/min, P=0.03) could probably be attributed to local release of the former from the pancreas, as the peritoneal clearance of lipase (highly anionic) was higher than predicted and the difference remained during peritonitis. CONCLUSIONS: The peritoneal membrane constitutes a size- but probably not a charge-selective barrier for the transport of macromolecules between blood and dialysate during stable CAPD.

Adult↗
PubMed1996

Demonstration of aquaporin-CHIP in peritoneal tissue of uremic and CAPD patients.

Aquaporin-CHIP is a 28 kD channel forming integral membrane protein. It acts as an osmotically driven, water-selective pore. The presence of aquaporin-CHIP has been demonstrated in the proximal tubule in the kidney and in the pleura, as well as in other tissues. During peritoneal dialysis a dissociation between the transport of water and sodium using hyperosmolar solutions has been reported, suggesting the presence of ultrasmall pores. Water channels, like aquaporin-CHIP, could be the morphological equivalent of these pores. We investigated the possible presence of aquaporin-CHIP in cryo-sections of peritoneal tissue using affinity purified human anti-CHIP IgC (P. Agre, Baltimore, MD). Peritoneal biopsies (omenta) were obtained at catheter insertion in 2 uremic patients with end-stage renal disease, and at catheter reimplantation of 1 patient treated with continuous ambulatory peritoneal dialysis (CAPD) for two years. Peritoneal tissue obtained at autopsy from 1 patient who had been on CAPD for four years, but in whom CAPD had been discontinued for five months, was also studied. Aquaporin-CHIP antiserum specific staining was found in the endothelial cells of the peritoneal capillaries in all patients. No obvious difference in the intensity of staining was seen between uremic and CAPD patients. This demonstration of aquaporin-CHIP in human peritoneal endothelial cells supports the hypothesis of the existence of ultrasmall pores within the peritoneal membrane. These water channels facilitate the transcellular transport of water, induced by an osmotic gradient, in the absence of sodium transport. It may be the explanation for the dissociation of water and sodium transport that occurs during hyperosmolar solutions. Aquaporin-CHIP is present in human peritoneal endothelial cells in both uremic and CAPD patients. Aquaporin-CHIP may be the morphological equivalent of the ultrasmall pores within the peritoneal membrane.

Aquaporin 1↗
PubMed1996

Impaired initial cell reaction in CAPD-related peritonitis.

Our objective was to determine the incidence of peritonitis episodes with an impaired initial cell reaction (IICR:neutrophil number < 100 x 10(6)/L) over a period of ten years, and to find possible explanations for this unusual presentation of peritonitis. A retrospective review of the files of continuous ambulatory peritoneal dialysis (CAPD) patients included in the CAPD program 1984 and 1993 was done. Analysis of cytokine and prostanoid patterns during four peritonitis episodes with an IICR was compared to 12 episodes with a normal initial cell reaction (NICR). Dialysate cell numbers and immunoeffector characteristics of peritoneal cells were compared in 7 IICR patients in a stable situation and a control group of 70 stable CAPD patients. The setting was a CAPD unit in the Academic Medical Center in Amsterdam. Thirty-five CAPD patients who had one or more peritonitis episodes with an IICR and a control group of 249 CAPD patients were included in the study. The incidence of peritonitis with an IICR was 6%. These episodes occurred more than once in 51% of the patients who presented with IICR. In 72% the cell reaction was only delayed: a cell number exceeding 100 x 10(6)/L was reached later. Staphylococcus aureus was significantly more frequently the causative microorganism compared to all peritonitis episodes (PE) that occurred during the study period. Patients with IICR had lower dialysate cell counts in a stable situation, compared to a control group (p < 0.01). This was caused by a lower number of macrophages and CD4 positive lymphocytes. The phagocytosis capacity of the macrophages appeared to be normal. In a comparison of four PE with an IICR and 12 episodes with an NICR, the tumor necrosis factor-alpha (TNF-alpha) response was similar and occurred on day 1, also pointing to normally functioning macrophages. However, the maximal appearance rates of interleukin-6 (IL-6) and IL-8 occurred later in the episodes with IICR compared to NICR (day 2 vs day 1, p < 0.05). No differences were found in vasodilating prostaglandins, mesothelial cell markers (cancer antigen 125, phospholipids, hyaluronan), and mesothelial cell numbers in the stable situation nor during peritonitis. Peritonitis can present as abdominal pain in the absence of a cloudy dialysate. In some of the patients this presentation occurred more than once. This impaired, most often delayed, cell reaction was associated with a delayed secondary cytokine response. As IL-6 and IL-8 can be synthesized by mesothelial cells, this suggests an impaired functioning mesothelium. This could not be confirmed, however, by a lower number of mesothelial cells in effluent or lower dialysate levels of mesothelial cell markers.

Adolescent↗
PubMed1996

Effect of amino acid based dialysate on peritoneal blood flow and permeability in stable CAPD patients: a potential role for nitric oxide?

Amino acid dialysis solution 1.1% (Nutrineal) contains L-arginine, a substrate for nitric oxide (NO) synthesis. NO causes vasodilation in many organs. To investigate effects of the amino acid dialysis solution on peritoneal permeability and perfusion, standard peritoneal permeability analyses were performed in 10 stable CAPD patients; one with Nutrineal and another with glucose dialysate (Dianeal 1.36%). The mass transfer area coefficient (MTAC) of nitrate and cGMP were calculated to study a possible role of NO. The MTAC of CO2 was measured to estimate peritoneal blood flow. The MTAC of CO2 was higher during the 4-hour dwell with the amino acid solution: median 93 ml/min (amino acid solution) vs. 60 ml/min (glucose solution); p < 0.01. This suggests an increased peritoneal blood flow during the administration of amino acids. Also the MTACs of low molecular weight solutes were greater with amino acids compared to glucose: creatinine 11.6 ml/min vs. 10.0, urea 19.0 vs. 16.6, urate 9.5 vs. 8.0; p < or = 0.01 for all. This points to an increased effective peritoneal surface area during amino acids. The clearances of the macromolecules beta 2-microglobulin and alpha 2-macroglobulin were also greater with the amino acid dialysis solution (p < 0.05), but there was only a small increase in the clearances of albumin and IgG. The increase in albumin loss during the 4-hour dwell with amino acids was only marginal. The MTACs of nitrate and cGMP were similar with the 2 solutions, without evidence of local production of these solutes. No difference was found between the 2 solutions in the dialysate concentrations of the prostaglandins PGE2, 6-keto-PGF1 alpha, PGF2 alpha and TxB2. The transcapillary ultrafiltration rate was higher during the amino acid dwell (p < 0.01), but no significant difference in net ultrafiltration was found, because the lymphatic absorption tended to be slightly greater with amino acids. The difference in transcapillary ultrafiltration with the 2 solutions was probably blood flow dependent, as the peritoneal filtration fraction was essentially the same in the 2 experiments. It is concluded that amino acid dialysis solution had a vasoactive effect. It mainly influenced the peritoneal blood flow and the effective peritoneal surface area. These effects could not be attributed to NO, as judged from nitrate or cGMP MTACs.

Adult↗
PubMed1996

Renal function influences interleukin-8 background production by cultured human mesothelial cells.

Previous studies have demonstrated that mesothelial cells (MC) are important in the local host defense system of the peritoneal cavity. Most studies on the function of MC are performed on MC derived from material of patients with normal renal function (NRF). The aim of the present study was to examine differences in interleukin (IL)-8 expression by MC from patients with NRF and from patients with end-stage renal disease (ESRD). Therefore, MC were isolated from the omentum and pleural exudate of patients with NRF, from spent effluent of stable peritoneal dialysis (PD) patients, and from omentum obtained during catheter implantation prior to PD treatment. MC were stimulated with increasing doses of IL-1 beta or tumor necrosis factor-alpha for 24 hours, after which the supernatant was analyzed for IL-8 content. The IL-8 background level of MC isolated from patients with NRF was significantly lower than the IL-8 background level of MC derived from patients with ESRD. Although IL-8 production appeared to be higher in the ESRD MC, this difference was not significant after stimulation. While the overall immunity is depressed in uremia, MC are activated. The relatively high background of IL-8 might lead to an insensitivity of neutrophils by blocking the receptors and explain their impaired chemotaxis in uremia.

Adult↗
PubMed1996

Similarities in functional state of the kidney in patients treated with CAPD and hemodialysis.

Differences have been reported in the decline of residual renal function in patients on continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD), but it is unknown whether the urinary handling of water and solutes is similar in these patient groups. Ten CAPD patients with residual renal function were investigated during a clearance period (CP) of 24 hours, and 11 HD patients were investigated during one interdialytic interval of three days. In CAPD patients the urinary volume excretion was 0.65 +/- 0.31 mL/min (mean +/- SD), and the inulin clearance was 3.85 +/- 2.82 mL/min. A negative correlation was found between the peritoneal net ultrafiltration rate and both the urinary volume excretion rate (r = -0.80, p < 0.01) and the fractional sodium clearance (r = -0.69, p < 0.05). In HD patients the urinary volume excretion increased from 0.36 +/- 0.36 mL/min during the initial eight hours of CP (HD-A) to 0.64 +/- 0.29 mL/min during the last ten hours of CP (HD-D, p < 0.05), and the inulin clearance increased from 1.9 +/- 1.3 (HD-A) to 2.9 +/- 1.1 (HD-D, p < 0.005). The fractional sodium clearance increased from 8.5 +/- 5.7% (HD-A) to 14.4 +/- 9.0% (HD-D, p < 0.05). It can be concluded that the fractional excretion of volume and fractional clearance of solutes were similar in patients treated with CAPD and hemodialysis. The most important regulating factor seems to be the volume status influenced by volume removal by peritoneal net ultrafiltration in CAPD patients, and volume expansion during the interdialytic interval in hemodialysis patients.

Adult↗
PubMed1995

Treatment of proliferative lupus nephritis with methylprednisolone pulse therapy and oral azathioprine.

OBJECTIVE: To evaluate the treatment of proliferative lupus nephritis with methylprednisolone pulse therapy and oral azathioprine. PATIENTS AND METHODS: Eighteen patients with severe proliferative lupus nephritis (Class III, IV or Vd according to criteria of the World Health Organization) were treated with intravenous methylprednisolone (MP) pulse therapy in combination with a low oral maintenance dose of prednisone (20 mg) and azathioprine (2 mg/kg). Thirteen patients (Group I) had a recent onset of clinical manifestations of nephritis at referral (mean and median 4 months). Five patients (Group II) had clinical signs of nephritis for a long time (median 4 years, mean 5 years) and were referred because of progressive renal failure. The mean plasma creatinine in Group I was 109 mumol/l with a mean GFR of 58 ml/min, the mean plasma creatinine in Group II was 284 mumol/l with a mean GFR of 12 ml/min. Renal histology in Group II was characterized by severe chronic damage (chronicity index 8-10). RESULTS: Short-term and long-term effects of treatment were excellent in Group I. The mean plasma creatinine was 68 mumol/l with a mean GFR of 102 ml/min at a mean follow-up of 7 years, median 4 years (range 1-15 years). All patients in Group II needed renal replacement therapy after a mean follow-up of 2.6 years, median 2 years (range 0-8 years). Major side-effects of treatment were only seen twice. CONCLUSION: Methylprednisolone pulse therapy in combination with low oral maintenance doses of prednisone and oral azathioprine is an effective and safe treatment for patients with severe active proliferative lupus nephritis. In patients with extensive irreversible lesions, this treatment has no or only a temporary effect.

Adolescent↗
PubMed1995

Dialysis treatment in patients with rheumatoid arthritis.

The results of dialysis treatment in 24 rheumatoid arthritis patients, 20 chronic rheumatoid arthritis (RA) and 4 juvenile rheumatoid arthritis (JRA), were analysed. Presence of secondary amyloidosis, renal function, morbidity and survival were examined. Amyloidosis was present in 13 patients. Especially among amyloidosis patients, renal function declined rapidly in the last year before dialysis started. On average, 63 days per patient-year were spent in the hospital, 58% was dialysis-related, mainly due to vascular access problems. Hospitalization was even more widespread in amyloidosis patients (79 days, 72% dialysis-related). Median survival in RA patients with amyloidosis was 11 months; in RA patients without amyloidosis this was 29 months. Two-year survival was only 1 out of 10 for the RA amyloidosis patients; for the RA non-amyloidosis patients this was 5 out of 6 (p < 0.01). Cardiovascular causes of death were most frequent. In conclusion, high morbidity and low survival make RA patients with amyloidosis a high-risk group on renal replacement therapy.

Adult↗
PubMed1995

The standard peritoneal permeability analysis: a tool for the assessment of peritoneal permeability characteristics in CAPD patients.

Peritoneal transport characteristics in CAPD patients are often assessed by the peritoneal equilibration test (PET), which uses a four hour dwell with glucose 2.27% dialysate. From the test, the dialysate/plasma ratio of creatinine (D/PCr), the dialysate/initial dialysate ratio of glucose (D/Do) and net ultrafiltration (NUF, drained minus instilled volume) are calculated. The standard peritoneal permeability analysis (SPA) is a modification and extension of the PET: glucose 1.36% dialysate is used, to which dextran 70 (1 g/liter) is added for the calculation of fluid kinetics. Mass transfer area coefficients (MTAC's) of low molecular weight solutes, clearances of proteins and the change in intraperitoneal volume (delta IPV) can be assessed. In this study the SPA was analyzed, and a comparison with the PET was made. A total number of 138 SPA's was analyzed in 86 different clinically stable patients. Normal values were calculated for both SPA and PET parameters in the same tests. Median (ranges) of comparable transport parameters from SPA and PET were: MTACCr, 10.4 ml/min (5.7 to 19.3); glucose absorption, 61% (35 to 87); delta IPV, 9.5 ml (-761 to 310); D/PCr, 0.76 (0.53 to 1.14); D/D0, 0.37 (0.13 to 0.56); NUF, -75 ml (-675 to 450). The agreement between SPA and PET was analyzed using the method of Bland and Altman. A fairly good agreement was present between NUF and delta IPV. Systematic errors were found when D/PCr and MTACCr were compared: D/P overestimated MTAC mainly in the low range, whereas in the high range values were underestimated. A similar pattern was seen for the transport parameters of glucose. In 40 patients negative net ultrafiltration was present, and possible reasons for this were assessed. In 9 patients no reason could be identified. It can be concluded that the SPA provides useful and extensive information on peritoneal transport parameters. Compared to the PET, the SPA has better discriminative power for the transport of glucose and creatinine.

Adult↗
PubMed1995

Time course of inulin and creatinine clearance in the interval between two haemodialysis treatments.

BACKGROUND: Urinary volume of haemodialysis patients with residual renal function increases during the interdialytic interval. The contribution of GFR to this change in water and solute excretion has not been quantified in detail. The creatinine clearance (Clc) as a determinant of the GFR may overestimate GFR caused by the tubular secretion of creatinine. Cimetidine has been used to inhibit the secretion of creatinine in non-dialysed patients. No data are available on its usefulness in haemodialysis patients. METHODS: Two identical interdialytic intervals (DI) of 3 days (DI-1, DI-2) were investigated in 11 patients. The interval between DI-1 and DI-2 was 1 week. During DI-2 cimetidine 800 mg daily was administered. Each DI was divided in four urine-collection periods. RESULTS: The water and solute excretion in DI-1 and DI-2 were similar. Urinary production increased from 0.37 +/- 0.30 ml/min to 0.66 +/- 0.33 ml/min (P < 0.05), inulin clearance (Cli) increased from 1.8 +/- 1.1 ml/min to 2.7 +/- 1.2 ml/min (P < 0.05), fractional sodium excretion from 9.0 +/- 5.7% to 14.5 +/- 9.0% (P < 0.05). In contrast to Cli the Clc showed no increase during the interdialytic interval both in DI-1 and DI-2. The overestimation of GFR by creatinine (Clc-Cli) decreased during DI-1 from 1.35 +/- 1.69 ml/min to 0.26 +/- 0.60 (P < 0.05) and during DI-2 from 1.01 +/- 1.33 ml/min to 0.10 +/- 0.67 (P < 0.01). The ratio Clc/Cli decreased during DI-1 from 1.78 +/- 0.53 to 1.09 +/- 0.19 (P < 0.01) and during DI-2 from 2.02 +/- 1.13 to 1.05 +/- 0.30 (P < 0.01). All parameters were not different between the comparable days of DI-1 and DI-2. CONCLUSION: We conclude that the urinary volume in the interdialytic interval is directly related to changes in GFR. During the interdialytic interval GFR increased and tubular secretion of creatinine decreased. The administration of cimetidine did not improve the accuracy of Clc as a measurement of GFR in end-stage renal failure.

Adult↗
PubMed1995

Interleukin-8 production by human mesothelial cells after direct stimulation with staphylococci.

Mesothelial cells (MC) are able to produce interleukin-8 (IL-8) after stimulation with IL-1 beta or tumor necrosis factor alpha. The aim of our study was to investigate whether MC are able to produce IL-8 after direct stimulation with clinically relevant bacteria. We observed a significant IL-8 response by the MC which were directly stimulated with viable staphylococci.

Cells, Cultured↗