Pediatric renal transplantation in Turkey: a review of 56 cases from a single center.

In order to assess certain aspects of pediatric kidney transplantation (Tx) in Turkey, we retrospectively analyzed the results of 56 of these pediatric procedures performed at our center. From January 1986 to January 1998, 56 pediatric renal Tx (29 males, 27 females; 0-17 yr of age) were carried out at Baskent University Hospital. All were first-time Tx. Fifty-one (91%) patients were on hemodialysis and four (7.3%) were on peritoneal dialysis prior to Tx. Pre-emptive Tx was performed for only one patient. Living-related donors (LRD) provided 47 (84%) of the transplanted organs and cadaver sources were utilized for nine (16%) patients. The mean cold ischemia time (CIT) for cadaveric donors (CD) was 38.6 h (range 23-56 h). Among living-related graft (LRG) recipients, the average waiting time for Tx was 4 months for Tx performed after 1990 and 8 months for those prior to 1990 (p < 0.05). Median length of hospital stay for Tx was 17 +/- 1.1 and 18 +/- 1.4 days for LRG and cadaveric graft (CG) recipients, respectively. Fifteen of 47 (33%) LRG recipients and six of nine (67%) CG recipients received anti-rejection treatment within 30 days following the Tx surgery. Graft failure developed in 16 (12 LRG, four CG) recipients. Two patients developed Kaposi's sarcoma, 17 and 3 months after Tx. There were total of six deaths (four with functioning grafts). The 1-, 3-, and 5-yr graft survival rates were 93%, 75%, and 63%, respectively, and corresponding patient survival rates were 96%, 92%, and 77%. The social and educational status of 27 patients with functioning grafts were also evaluated. Our results showed that 56% of patients ended their education before high school and only three patients have been married. The high rate of school drop-out and unemployment among pediatric renal transplant recipients in our population underline the need for a more intensive rehabilitation program.

Gastroduodenal lesions and Helicobacter pylori in children with end-stage renal disease.

Thirty-seven children with end-stage renal disease were evaluated for gastroduodenal lesions by upper gastrointestinal endoscopy between January 1993 and January 1998. The mean (+/-SD) age of the patients was 14.3+/-2.4 years (range 9-17 years). Endoscopic examination was abnormal in 17 patients (46%). The lesions were antral gastritis plus bulbitis (n=6), nodular bulbitis (n=4), antral gastritis (n=4), and duodenal ulcer (n=3). Fifteen patients had symptoms related to gastroduodenal disease, whereas 22 patients were asymptomatic at the time of endoscopic examination; 80% of the symptomatic and 23% of the asymptomatic patients had gastroduodenal lesions on endoscopy. Antral mucosal biopsy was taken from 26 of 37 children for the detection of Helicobacter pylori by the urease test. H. pylori was detected in 10 of 16 patients with gastroduodenal lesions (8 symptomatic, 2 asymptomatic). None of the patients with normal endoscopic examination were positive for H. pylori. Thus, we have demonstrated a significant number of gastroduodenal lesions and their frequent association with H. pylori in our pediatric renal transplant candidates. Our results emphasize the importance of gastrointestinal evaluation in these patients. Endoscopic examination should be considered in symptomatic patients and in areas where H. pylori is endemic.

Peritoneal loss of insulin-like growth factor-I and binding proteins in end-stage renal disease.

The kinetics of peritoneal transport of insulin-like growth factor (IGF) system-related proteins during dialysis is not well characterized. We studied temporal changes in dialysate and serum concentrations of IGF-I and IGF-II as well as IGF binding protein (BP)-1, -2, and -3 in ten children with end-stage renal disease (ESRD) undergoing continuous cycling peritoneal dialysis (CCPD) during a 4-h peritoneal equilibration test (PET). Dialysate concentrations of IGF-I, IGF-II, and all three IGFBPs demonstrated a time-dependent increase during PET. Despite their transport, the serum concentrations of these proteins did not change significantly during the PET. Dialysate/serum ratios for IGF-I, IGF-II, and IGFBP-1, -2, and -3 were significantly increased at 2 h and increased further at 4 h, at which time values averaged 1.3+/-0.2%, 3.1+/-0.5%, 6.2+/-1.0%, 2.4+/-0.2%, and 1.3+/-0.2% of serum levels, respectively. The transperitoneal clearance (microl/min per 1.73 m2) of the three IGFBPs was inversely related to both their molecular weight and plasma concentration. However, peritoneal clearance of IGF-I and -II was similar to that of the larger and more-abundant IGFBP-3. Mass transfer rates (microg/h per 1.73 m2) for the IGFs and their binding proteins were directly proportional to their prevailing plasma concentration. Based on estimates of mass transfer, only a small molar excess of IGFBPs was removed from the circulation relative to the combined molar concentration of IGF-I and IGF-II. Hence, it seems unlikely that any beneficial effect of CCPD on growth in children with ESRD is mediated via a preferential loss of IGFBPs into the dialysate fluid.

Removal of Pb(II), Cd(II), Cu(II), and Zn(II) from Aqueous Solutions by Adsorption on Bentonite

Removal of Pb(II), Cd(II), Zn(II), and Cu(II) from aqueous solutions using the adsorption process on bentonite has been investigated. In order to find out the effect of temperature on adsorption, the experiments were conducted at 20, 35, and 50degreesC. For all the metals, maximum adsorption was observed at 20degreesC. The rate of attaining equilibrium of adsorption of metal ions follows the order Zn(II) > Cu(II) > Cd(II) > Pb(II). Equilibrium modeling of the adsorption showed that adsorption of Pb(II), Cd(II), and Cu(II) were fitted to a Langmuir isotherm, while the adsorption of Zn(II) was fitted to a Freundlich isotherm. Dynamic modeling of the adsorption showed that the first order reversible kinetic model was held for the adsorption process. The overall rate constant k', the adsorption rate constant k1, the desorption rate constant k2, and the equilibrium constant Ke for the adsorption process were calculated. From the results of the thermodynamic analysis, standard free energy DeltaG0, standard enthalpy DeltaH0, and standard entropy DeltaS0 of the adsorption process were calculated.

Plasminogen activator inhibitor-1 and peritoneal transport in peritoneal dialysis patients.

Plasminogen activator inhibitor-1 (PAI-1) is involved in the accumulation of extracellular matrix in various tissues. Since peritoneal interstitium is one of the resistance sites for transport during peritoneal dialysis (PD), the peritoneal PAI-1 level may have a significant effect on peritoneal transport. It was the purpose of this study to examine the associations between plasma or dialysate PAI-1 levels and the variables of peritoneal transport during peritoneal equilibration tests (PET) in 25 stable, adult PD patients. The dialysate PAI-1 levels increased with dwell time. Hematocrit was a positive predictor of plasma PAI-1 concentration and the change of dialysate PAI-1 amount scaled by body surface area (delta DPAI/ BSA). The peritoneal clearance of PAI-1 was higher than expected for its molecular size, suggesting a local production of PAI-1 in peritoneal tissue. The mass transfer coefficient of creatinine scaled by BSA (MTCcr/BSA) was a positive predictor of delta D PAI/BSA, suggesting the diffusion of plasma PAI-1 into the peritoneal cavity also accounted for part of the increased dialysate PAI-1 levels during PET. delta DPAI/BSA was a positive predictor of MTC of urea (ur) MTCwr/BSA and MTCcr/BSA, parameters for diffusive transport. Our findings are consistent with the hypothesis that peritoneal PAI-1 level has a significant effect on peritoneal transport during PD.

Pediatric renal transplantation.

Renal transplantation in children is a most rewarding treatment that dramatically changes the overall health and lifestyle of children with ESRD. Complexities in different aspects of renal transplantation in children are obvious. Optimum technical conditions and drug therapy must be provided for the success of renal transplantation. Application of recent advances in immunology and long-term care to clinical transplantation continue to improve graft and patient survival rates. Optimization of growth and development also can be improved with the use of rhGH.

Plasminogen activator inhibitor-1 and peritoneal transport in diabetic and non-diabetic peritoneal dialysis patients.

Plasminogen activator inhibitor-1 (PAI-1) is an important regulator of plasminogen activators and has been shown to be involved in the accumulation of extracellular matrix (ECM) in various tissues. Since peritoneal interstitium is one of the main resistance sites of peritoneal transport, the level of PAI-1 in the peritoneum may have a significant effect on water and solute transport during peritoneal dialysis (PD) via its effect of peritoneal ECM. Therefore, we studied the associations between plasma or dialysate PAI-1 levels and the peritoneal transport during standard peritoneal equilibration test (PET) in 8 diabetic and 8 non-diabetic stable PD patients who were matched for their demographical data. There were no differences in plasma PAI-1 levels and PET variables between these two groups of patients. In each group, there was an increase in dialysate PAI-1 level with dwell time as a result of the diffusion of plasma PAI-1 into peritoneal cavity and the local production and release of PAI-1 in peritoneal tissue. However, the extent of this increase was less in the former. In non-diabetic patients, the change in dialysate PAI-1 amount was a significant positive predictor for the diffusive transports of urea and transport. These results are consistent with the hypothesis that peritoneal PAI-1 has a significant effect on peritoneal transport during PD. Further studies including more patients are needed to confirm our observations, and studies providing more direct evidence are needed to test this hypothesis.