Successes and pitfalls of chronic peritoneal dialysis in infants - a Polish nationwide outcome study

INTRODUCTION

Peritoneal dialysis (PD) is a preferred method of renal replacement therapy for end-stage renal disease in children. Recent advances have allowed chronic PD to be provided to children of all ages and sizes.

MATERIAL AND METHODS

The study was designed as a national (10 dialysis centres), multicentre retrospective analysis of the medical history of 33 children who started chronic peritoneal dialysis in their infancy between 1993 and 2005, with a follow-up period of at least 24 months.

RESULTS

The nutritional status of the infants was unsatisfactory. The mean SDS of body weight at the start was -2.0, at 1 year of age -1.7. Only 40% of infants were adequately nourished at 1 year of age. Long-term follow-up analysis showed that 12 children received a kidney transplant, 13 were still on dialysis (4 changed method) and 6 died (mortality rate in the first year of life of 9%). In 2 children we observed an improvement of renal function. We observed a relatively high (1/8.8 patient-months) peritonitis rate in the analysed children when compared to 1 : 22 patient-months in all children undergoing PD in Poland.

CONCLUSIONS

The results of our survey have shown that the management of dialysed infants is still a challenge for the medical team and families, but long-term results of the therapy are encouraging.

[Congenital and genetic related causes of end-stage renal disease--data from Polish Registry of Renal Rreplacement Therapy in Children 2000-2004]

One of the objectives of Polish Registry of Renal Replacement Therapy in Children established on 31st Dec. 2000 was to collect complete data on etiology of end stage renal disease (ESRD) in polish children.

MATERIAL AND METHODS

Data on 469 patients (251 boys, 218 girls) aged 0-22 years treated with renal replacement therapy (RRT) at 13 pediatric dialysis units in Poland from 2000 to 2004 were analyzed. The mean age at start of dialysis was 10 years and 3 months. Renal diseases were defined according to EDTA coding system. Data is presented for the whole group, in 5-year age groups and separately for both sexes.

RESULTS

Congenital and genetic renal diseases were the cause of ESRF in 56% of the polish population of children and adolescents on RRT. 39% of causes were acquired diseases, 5% remained unidentified. Congenital and genetic causes dominated in children < 5 years of age (71%). They accounted for 49%, 61% and 45% of causes in the consecutive 5-year age groups. The most numerous group of congenital diseases leading to ESRF were uropathies 37% and 25% of causes in the consecutive age groups. In boys the most frequent uropathy was obstructive uropathy (25%), the majority caused by posterior urethral valves. In girls the most frequent uropathies were reflux nephropathy (10%) and nephropathy secondary to neurogenic bladder (9%). Uropathies were followed by renal hypo-dysplasia without urinary tract anomalies (11%) and cystic diseases (10%).

CONCLUSIONS

Congenital kidney anomalies and genetic diseases are the leading cause of end-stage renal disease in children up to 15 years of age.

[Chronic peritoneal dialysis in infants--preliminary results of the multicenter survey]

We retrospectively analysed peritoneal dialysis treatment in 29 infants dialysed in 9 paediatric centres in Poland in the years 1993-2004. The mean age at the start of dialysis was 4.9 +/- 3.5 months (range 2 days to 11 months), mean body mass 5.6 +/- 2.5 kg (range 2.5 to 11 kg). The mean duration of PD was 6.8 +/- 3.9 in the first year of life and total duration of the therapy 34 +/- 27 months. Of the 29 infants 4 died (2 in infancy), 11 underwent renal transplantation, in 2 children PD was stopped (they received a conventional treatment) and 12 were still dialysed at the date of data collection. The peritonitis rate was 1/9.5 patient-month and exit site infection rate 1/16 patient-month up to 1 year of life. 9 children (31%) required hernia repairs and in 9 catheters were replaced. Chronic peritoneal dialysis in infants is associated with high risk of infections and surgical complications and remains a challenge for paediatric nephrologists.

[Peritoneal transport properties for glucose and creatinine in Polish children and adolescents on chronic peritoneal dialysis]

INTRODUCTION

The mode of PD treatment is dependent on the individual transport properties of the peritoneal membrane. Two multicentre trials performed in the U.S. (PPDSC) and Europe (MEPPS) have established reference curves for solute equilibration in children performed with the use of 1100 ml/m2 fill volume in the former and 1000 ml/m2 in the latter study.

AIM OF THE STUDY

Assessment of basal peritoneal membrane equilibration based on PET tests in polish children and adolescents treated with chronic peritoneal dialysis.

MATERIAL AND METHODS

58 PET tests from patients treated at 8 Polish PD centres were analysed. The mean time of performing PET test was 6,5 months after the start of PD therapy. All of the patients had been peritonitis free from onset. The mean fill volume was 1021 (906-1170) ml/m2.

RESULTS

Based on the results of creatinine and glucose equilibration we established basal peritoneal solute transport curves for polish PD children using an average fill volume of 1020 ml/m2. The following values were obtained at 4hrs of dwell time for 2.27% glucose solution: D/P for creatinine = 0.68 +/- 0.15 and D/Do for glucose = 0.39 +/- 0.12.

CONCLUSIONS

The DIP creatinine equilibration curves were similar to the previously published reference curves for children, whereas those for glucose was significantly lower. Using a fill volume scaled to body surface area of 1020 ml/m2 equilibration curves for glucose and creatinine are similar in children over 1 year of age and adults.

Abnormal Cytokine Synthesis as a Consequence of Increased Intracellular Oxidative Stress in Children Treated with Dialysis

BACKGROUND/AIM

End-stage renal disease (ESRD) induces a clinical state of immunodeficiency with a higher incidence of infections and higher mortality due to infectious complications compared with the normal population. The definite mechanism responsible for the host defense alterations is not well understood. The aim of the study was to investigate intracellularly the relationship between cytokine synthesis and oxidative stress in peripheral blood lymphocytes in children with ESRD.

METHODS

Twenty-one children (age 11.7 +/- 5.8 years) with ESRD treated with hemodialysis (HD; n = 10) and peritoneal dialysis (PD; n = 11) were studied. Nine healthy children of comparable age formed the control group. To determine intracellular oxidative stress we used dihydrorhodamine-123 (DHR), which after oxidation to rhodamine-123 (RHO) emitted a bright fluorescent signal. Intracellular oxidation of DHR in T lymphocytes reflected intracellular oxidative stress. The intracellular synthesis of cytokines (IL-2, IFN-gamma, IL-4, IL-6) was also measured. Both parameters were detected at a single-cell level by flow cytometry. Lymphocyte subsets were evaluated using the monoclonal antibodies conjugated with fluorochromes.

RESULTS

We found that in T lymphocytes the mean fluorescence intensity (MFI), which reflected intracellular oxidative stress, was increased in ESRD patients compared to the controls (CD3+: 34.77 +/- 11.55 vs. 22.55 +/- 4.97, p < 0.01; CD3+CD8+: 34.31 +/- 12.17 vs. 20.77 +/- 4.89, p < 0.01; CD3+CD4+: 36.06 +/- 6.98 vs. 24.44 +/- 7.68, p < 0.001). HD patients showed slightly higher MFI compared to PD patients in CD3+ cells (39.32 +/- 11.70 vs. 30.63 +/- 10.20, NS), in CD3+CD8+ cells (37.90 +/- 14.32 vs. 31.06 +/- 9.34, NS) and in CD3+CD4+ cells (40.10 +/- 2.28 vs. 29.33 +/- 7.06, p < 0.001). The intracellular synthesis of IL-2 was higher in ESRD patients compared to the controls, both in CD3+ cells (31.34 +/- 9.80 vs. 20.49 +/- 15.26%, p < 0.05) and in CD3+CD4+ cells (36.10 +/- 8.69 vs. 24.03 +/- 16.95%, p < 0.05). The intracellular synthesis of IFN-gamma, IL-4 and IL-6 was significantly lower in the ESRD group compared to the controls. Interestingly, in patients treated with HD, negative correlations between the degree of intracellular oxidative stress and intracellular cytokine synthesis in CD3+ lymphocytes were found.

CONCLUSION

Our results show that patients with ESRD, especially those treated with HD, present increased oxidative stress in T lymphocytes, which may lead to decreased cytokine synthesis and abnormal immune response.

Beneficial in vitro effect of N-acetyl-cysteine on oxidative stress and apoptosis

Chronic renal failure (CRF) is usually accompanied by abnormalities of both humoral and cellular immune response. The aim of the study was to investigate the influence of N-acetyl-cysteine (NAC) on intracellular oxidative stress and apoptosis rate of T lymphocytes in children with CRF. Twenty-two children (aged 4-16, mean 7.4) with CRF treated with dialysis were enrolled in the study. Intracellular reactive oxygen species (ROS) production was quantified by mean rhodamine 123 (RHO) fluorescence intensity with flow cytometry. Annexin V FITC was used for identifying apoptotic cells. Mean fluorescence intensity (MFI), which reflected intracellular oxidative stress in T lymphocytes, was increased in patients with CRF compared with the controls (CD3+: 31.58+/-11.58 vs 22.55+/-4.97, p = 0.043; CD3+CD4+: 32.50+/-8.59 vs 27.75+/-12.76, NS; CD3+CD8+: 32.10+/-11.85 vs 20.77+/- 4.89, p =0.012). Apoptotic T lymphocytes occurred more frequently in patients with CRF treated with hemodialysis (HD) (11.36+/-6.96%) than in the controls (6.14%+/-3.36%; p = 0.025). After 24 h incubation with NAC MFI and apoptosis rate decreased significantly in all subpopulations of lymphocytes. NAC, as a strong antioxidant, has a favorable effect on intracellular oxidative stress and apoptosis rate of T lymphocytes in patients with CRF. A decreased apoptosis rate may have positive effect on functional abnormalities of T cells already found in patients with CRF.

[Influence of vitamin E and N-acetylcysteine on intracellular oxidative stress in T lymphocytes in children treated with dialysis]

End-stage renal disease (ESRD) patients are subjected to enhanced oxidative stress. Excess of reactive oxygen species (ROS) may lead to the functional disabilities of lymphocytes. The aim of the study was to investigate the effect of vitamin E and N-acetylcysteine (NAC) on antioxidant status and intracellular oxidative stress in T-cells in children treated with dialysis.

MATERIAL AND METHODS

18 children treated with dialysis (hemodialysis n = 5 and peritoneal dialysis n = 13) were enrolled into the study. The age range was 2-20 ys. with a mean of 10.94 +/-5.86 ys. Vitamin E and NAC were given for six months orally. Throughout the study total antioxidant status (TAS), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity, and intracellular oxidative stress in T lymphocytes was measured.

RESULTS

In children treated with dialysis, TAS was significantly reduced compared to the controls (p = 0.012). We found no differences in GPx and SOD activities between patient and control groups. Mean fluorescence intensity (MFI), which reflected intracellular oxidative stress, was significantly increased in: CD3+, CD3+CD4- and CD8+CD28-. After six months of antioxidant treatment, a significant reduction in MFI was noted in most T-cell subsets (p < 0.001). MFI in T-helper cells remained unchanged. Although there was a trend toward rise in TAS and GPx activity, only significant differences in SOD activity were found (p = 0.022).

CONCLUSIONS

In children with ESRD treated with dialysis reduced TAS coexists with enhanced intracellular oxidative stress in T lymphocytes. The combined treatment with vitamin E and NAC lead to the reduction in oxidative stress within T-cells that might be of therapeutic value in dialyzed patients.

Heavy metals biosorption from aqueous solution by simple eucaryotic organisms

Biosorption of cadmium and chromium (III) ions by means of selected yeast species has been estimated. Kinetics and equilibrium measurements have shown the reliable efficiency of both metals removal for Candida tropicalis. The influence of pH and ionic strength on biosorption process has been examined as well. For both metals the adsorption isotherms have been presented. The equilibrium of chromium (III) sorption has appeared compatible to Langmiur model and the maximum sorption capacity has been determined.

[Clinical investigations of children with chronic renal failure and peritonitis treated with peritoneal dialysis]

Peritonitis and catheter-related infection are the most-common complications of peritoneal dialysis treatment. The aim of study was to analyse frequency causes, effectiveness of therapy and risk factors of peritonitis in patients treated with continuous peritoneal dialysis (CAPD). We described 13 patients aged 6-21 years, mean 12 years, who initiated CAPD between 1995 to 2000. The most-common primary cause of end-stage renal disease were chronic glomerulonephritis in 8 children, renal dysplasia in 3 children, hemolytic-uremic syndrome in 1 child and obstruction uropathy in 1 child. Peritonitis rate was 1 episode for 9 patient months. Staphylococcus aureus was the most-common infection factor. We performed exchange of catheter in 8 children. Causes of exchange were exit site infection, cuff excision, tunnel infection and peritonitis. Children were usually treated with two antibiotics for two weeks. Effect of treatment was better in these episodes treated longer than two weeks. As a risk factors of increasing peritonitis relapses we suggest immunosuppressive therapy, protein deficiency, catheter dislocation, not adequate education of patient family and chronic skin infections. We observed lower rate of peritonitis relapses in patients treated longer than two years on CAPD.

CONCLUSIONS

1. In patients with chronic renal failure treated with CAPD the preceding immunosupressive therapy increases the frequency of peritonitis. 2. More intensive treatment can cause decreasing frequency of peritonitis relapses. 3. Some risk factors increase the frequency of peritonitis relapses. 4. A better education of patient and his family decreases the frequency of peritonitis relapses.

Macrophages during infection with Trichinella spiralis in mice

Behaviour of macrophages in experimental mice trichinellosis was investigated using the immunoenzymatic technique with monoclonal antibodies CD11b/CD18 within the framework of avidin-biotin-DAB. The maximum and earliest mobilization of macrophages 7 day post infection (dpi) was observed in the lamina propria of the intestinal mucosa. The highest level of macrophages in the muscles tissue was noted on day 21 of infection, however as early as in 28 dpi, their maximum level was observed inside the larval capsules. They line, especially between 35-42 dpi internal capsule surface.

The cells observed inside capsules of larvae in the course of experimental trichinellosis in mice

In the course of trichinellosis in mice the numerous cells inside larval capsules were observed. Beginning on 14 day post infection (dpi) they were seen in about 7% of infected muscles fibers but at 21 dpi the percentage of capsules with the cells amounted to 77. In the next stage of infection the number of capsules containing cells continued to increase and reach almost 100% at 60 dpi. The identification of the cells was carried out by the indirect immunoenzymatic method using anti-CD4+, anti-CD8+ and anti-macrophage (Mac-1 antigen) monoclonal antibodies. In course of observation the level of CD4+ cells decreased from 11.3 to 0.7, of CD8+ from 17.7 to 3.0 and of macrophages from 71.0 to 23.1%. The most numerous CD4+ cells were seen at 14 dpi while the CD8+ and macrophages at 21 dpi. Beginning on 28 dpi negatively reacting cells inside larval capsules were also observed. The number of these cells increased from 23.8 to 73.2% at 60 dpi and their identification requires further investigations. The role and the function of all these cells are discussed.

[The influence of ricin on the course of experimental infections of mice with Trichinella spiralis]

Mice received 5 ng of ricin 24 hours after infection (experiment I) or 1 ng of ricin twice, 24 hours and 17 days of infection (experiment II). Animals were killed in 7, 14, 21, 28, 35, 42 and 60 days after infection. In the jejunum and masseter muscle sections, CD4+ and CD8+ lymphocytes, mast cells and eosinophils were studied. Heavy suppression of CD8+ lymphocytes, strong eosinophils and less pronounced mast cells stimulation was observed in the jejunum of mice received ricin (experiment I). Worm expulsion in intestine was faster than in the control (opposite results in experiment II). The composition of cells infiltration in the muscle was in both experiments similar to the control, however, fewer CD4+ lymphocytes were observed in larva capsule and there were fewer muscle larvae. Therefore CD8+ cells are believed to take part in restricting only the muscle stage of trichinellosis.

[One center's experience with fibrinolytic treatment in children]

Fifteen children treated with fibrinolytic agents are presented. The most frequent indication was thromboembolic disease (TED). Eleven patients received streptokinase, 5-urokinase and 3-tissue plasminogen activator. Concomitant heparin was administered to 9 patients with TED. Total resolution was achieved in 9 children, partial improvement in 5; 1 child died during treatment without any improvement. Bleeding complications were observed in 6 patients, 1 of them died due to haemorrhagic stroke. According to the literature and our own experience, we recommend fibrinolytic agents as the treatment of choice for severe TED also in children.

[The influence of phytohemagglutinin P on CD4+ and CD8+ cells in the course of experimental trichinellosis in mice]

Experiments were carried out with mice of CFW inbred strain infected with 200 Trichinella spiralis larvae and divided into two groups: experimental and control. The experimental mice were injected with phytohaemagglutinin P (PHA-P), 24 h before infection. The all animals were killed between 7-133 days post infection and the pieces of spleens, mesenteric lymph nodes, jejunum and masseter muscles were sectioned in a cryostat and examined with monoclonal antibodies (anti-Thy 1, 2, anti-CD4+ and anti-CD8+) by immunoenzymatic method. In the animals treated with PHA-P, more numerous CD4+ cells were observed in comparison with the control. The CD8+ cells were stimulated only in the muscles. The most important problem were the CD4+ and CD8+ cells inside the larvae capsules. The role of the CD4+ and CD8+ cells in the immunopathological changes in the course of trichinellosis was discussed.

An unusual pedigree with microcornea-cataract syndrome

A pedigree with 14 patients affected with microcornea-cataract (MC) syndrome is described. MC syndrome is very rare and this pedigree is probably the sixth to be reported. Transmission is most likely autosomal dominant, but the unusual feature of the present family is the fact that the proportion of affected members is so high that one is tempted to suspect preferential transmission of the chromosome carrying the MC gene.