[Favourable effects of kidney transplantation on vascular condition of patients: Potential prognostic significance of non-invasive measurement of arterial stiffness]. / A vesetranszplantáció pozitív hatásai a betegek angiológiai státuszára: Az artériás funkció (stiffness) noninvazív mérésének lehetséges szerepe az elorejelzésben.

INTRODUCTION: Development of atherosclerosis is accelerated in kidney transplant patients. Impaired metabolic pathways have complex effect on the arterial wall which can be measured by non-invasive techniques. Only few data are available on the change of stiffness parameters in the postoperative course. Therefore, in this study the authors analysed the stiffness parameters of kidney transplant recipients during the perioperative period. AIM: Non-invasive clinical trial of the arterial functional parameters in the early postoperative period. METHOD: Seventeen successful primary kidney transplant patients with uneventful postoperative period (8 females, 9 males; age, 46.16 ± 12.19 years) were involved in this short-term prospective longitudinal study. The authors analysed correlations between non-in vasively assessed stiffness parameters (pulse wave velocity PWV, augmentation index - AIx). Stiffness parameters were measured with a TensioMed Arteriograph. These parameters were assessed before the transplantation, as well as 24 hours, 1 and 2 weeks after surgery under standard conditions. RESULTS: It was found that PWV (p = 0.0075) and AIx (p = 0.013) improved significantly. There was no significant change in case of PP and the other monitored parameters. Serum creatinine decreased (p = 0.0008) and glomerular filtration rate increased significantly (p = 0.0005). CONCLUSIONS: Along with the available data in the literature, the findings suggest that kidney transplantation has a positive effect on the arterial function. Improvement can be detected non-invasively with Arteriograph in the early postoperative period.

[First outcomes, since being full member of Eurotransplant. A single center experience of cadaveric kidney transplantation]. / Eredményeink a teljes jogú Eurotransplant-tagság óta. A Debreceni Vesetranszplantációs Központ tapasztalatai.

INTRODUCTION: The first renal transplantation was completed in 1991 at the University of Debrecen. In 2013 Hungary joined Eurotransplant. AIM: The authors retrospectively compared the trends. METHOD: Comparison between Period A (from January 1, 2008 to August 31, 2013) and Period B (from September 1, 2013 to October 22, 2015). RESULTS: The proportion of living transplants rose from 3.5% to 9.1 %. During period B over 25% of utilized donors were over 60 years of age. Recipients with body mass index above 30 kg/m(2) increased from 12% to 31%. Prevalence of diabetes among recipients rose twofold. Uretero-neocystostomy was used during period A (99%) while in period B end to side uretero-ureteral anastomosis has also gained popularity (68%). In 2013 the authors introduced routine use of induction treatment. Acute rejection rate decreased from 34% to 8%. The rate of surgical complications did not change. Acute bacterial infections decreased from 41% to 33%. Cumulative renal allograft 1, 3 and 5 year survival rates were 86.6%, 85% and 82.7% in group A vs. projected rates 88%, 84% and 84% in group B, respectively. CONCLUSIONS: Despite the growing proportion of expanded criteria donors, the authors were able to maintain a low incidence of delayed graft function and a favorable graft survival. Since 2013 the authors introduced treatments for acute humoral rejection according to international standards.

[The effect of the I/D polymorphism of the angiotensin-converting enzyme gene on the cardiovascular risk and graft survival of kidney transplant patients]. / Az angiotenzinkonvertálóenzim-gén I/D polimorfizmusának hatása a vesetranszplantált betegek cardiovascularis rizikójára és a grafttúlélésre.

INTRODUCTION: Renal transplantation provides longer life expectancy in patients with renal failure. Nonetheless, this improved life expectancy is still shorter than that for the general population. The main couse of death in renal transplant patients is cardiovascular disease, and chronic allograft nephropathy is the most significant cause of graft loss. Genetic polymorphisms of the renin angiotensin system have been implicated in both chronic allograft nephropathy and fatal cardiovascular diseases. AIM: The long term goal of the authors was to improve the survival of renal transplanted patients. The authors aimed to identify novel biomarkers which correlate with the survival of the transplant organ and the recipient with a special attention to elements of the renin-angiotensin system. METHOD: A retrospective clinical trial was performed involving 72 renal transplanted patients. Angiotensin-converting enzyme I/D genotypes and activity, kidney function and morphological properties of the heart were determined. RESULTS: A significant positive correlation was found between the DD genotype of the angiotensin-converting enzíme gene, and the DD genotype predicted severe left ventricular hypertrophy. CONCLUSIONS: These findings suggest that the I/D genotypes of the angiotensin-converting enzyme gene predict not only the expected survival of the transplanted organ, but also that of the patient. Patients with the DD genotype are more susceptible for transplant failure. These patients should be identified and a special attention should be made on their pharmacological treatment (renin-angiotensin system inhibition), and their complience should also be maintained.

Effect of nutritional status on human paraoxonase-1 activity in patients with chronic kidney disease.

BACKGROUND/METHODS: The association between nutritional status, antioxidant human paraoxonase-1 (PON1) activity and low grade inflammation in hemodialized (HD) patients with chronic kidney disease (CKD) is unclear. The aim of this study was to determine PON1 paraoxonase and lactonase activities, ADMA, adiponectin and leptin concentrations, and to clarify the relationship between paraoxonase activity and a set of cardiovascular risk factors in malnourished, normal weight and obese HD patients; 114 HD patients with end-stage renal failure were enrolled. RESULTS: Leptin levels were significantly higher and PON1 paraoxonase activities were significantly lower in obese patients compared to the other groups. Plasma adiponectin concentration was significantly lower in obese subjects compared to malnourished patients. Paraoxonase activity was negatively correlated with CRP level in HD and malnourished patients. Furthermore, we found significant inverse correlation between paraoxonase activity and BMI in the whole patient group. In multiple regression analysis, PON1 lactonase activity, CRP level and leptin concentration proved to be independent predictors of paraoxonase activity. CONCLUSION: Despite the previous findings of reverse epidemiology for the mortality rate of HD patients, further studies are needed to clarify the effects of nutritional state on atherosclerosis in obese and malnourished patients with end-stage renal failure.

Decreased paraoxonase 1 (PON1) lactonase activity in hemodialyzed and renal transplanted patients. A novel cardiovascular biomarker in end-stage renal disease.

BACKGROUND: Human paraoxonase-1 (PON1) has also been described as a lactonase. Decreased PON1 lactonase activity was found to be a predictor of cardiovascular disease. Homocysteine thiolactonase activity may prevent proteins from homocysteinylation and is thought to be a protective factor against the progression of atherosclerosis. Previous studies have demonstrated decreased PON1 paraoxonase activity in hemodialyzed (HD) and renal transplant (TRX) patients; however, lactonase activity has not been investigated. We aimed to determine the paraoxonase and lactonase activities and to clarify the relationship between lactonase activity and a set of cardiovascular risk factors, such as homocysteine, cystatin C and asymmetric dimethylarginine (ADMA) levels, in HD and TRX patients and in healthy controls. METHODS: One hundred and eight HD and 78 TRX patients and 63 healthy controls were involved in the study. Paraoxonase and lactonase activities (paraoxon and gamma-thiobutyrolactone as substrates) were measured spectrophotometrically. ADMA level was determined with sandwich enzyme-linked immunosorbent assay. RESULTS: Both HD and TRX patients had significantly lower lactonase activities compared to the control group (P<0.05). Significantly lower paraoxonase activities were found in HD patients compared to the TRX group (P<0.05). Significant negative correlation was found between lactonase activity and ADMA level in the whole study population (P<0.001), while paraoxonase and lactonase activities showed significant positive correlation (P<0.001). Multiple regression analysis identified paraoxonase activity and homocysteine level as independent predictors of lactonase activity. CONCLUSION: Lactonase activity is a potential new predictor of cardiovascular risk in renal failure. Measurement of lactonase activity is recommended in future studies on HD and TRX patients.

Discordance in human paraoxonase-1 gene between phenotypes and genotypes in chronic kidney disease.

BACKGROUND: Human serum paraoxonase-1 (PON1) is a high-density lipoprotein-associated ester hydrolase which can inhibit low-density lipoprotein oxidation and has an antiatherogenic effect. Two common polymorphisms are known in the PON1 gene in humans (at positions 55 and 192), from which the latter gene alteration has been mainly attributed to alter the activity of the protein. Moreover, significantly reduced PON1 activity was found in chronic kidney disease (CKD) and renal transplant patients. METHODS: The aim of the present study was to investigate the genotype and phenotype distribution of the PON1 gene as well as its end product activity in patients with CKD (n = 117), in renal transplant recipients (n = 146) and in reference subjects (n = 1,180). RESULTS: Unexpectedly high discordances between phenotype and genotype assessments were observed in all studied groups (28.2% in the CKD, 20.55% in the transplant and 30.9% in the reference group). Arylesterase activity was significantly lower in the CKD group compared to the reference sample. There were no significant differences between patients and the reference group in the frequencies of polymorphisms PON1-55 and PON1-192. PON1 activity did not differ in patients compared to the reference group. CONCLUSIONS: Both PON1 phenotype and genotype determinations are necessary to estimate PON1 status.

Serum cystatin C is a determinant of paraoxonase activity in hemodialyzed and renal transplanted patients.

BACKGROUND: Human paraoxonase-1 (PON1) inhibits LDL-oxidation and atherogenesis, and possesses lactonase activity. Decreased PON1 activity was found in hemodialyzed and renal transplanted patients. Cystatin C plays a protective role in atherosclerosis, and is a new, sensitive marker of renal function. The relationship between these two markers in renal failure has not been investigated. AIMS: The goal of this study was to clarify the relationship between PON1 activity, cystatin C and homocysteine in chronic renal failure. We also determined the levels of oxidatively modified LDL (oxLDL) and thiobarbituric acid reactive substances (TBARS) to characterize lipid peroxidation. PATIENTS AND METHODS: 74 hemodialized (HD), 171 renal transplanted patients (TRX), and 110 healthy controls (C) were involved in the study. PON1 activity and TBARS levels were measured spectrophotometrically. OxLDL level was determined with sandwich ELISA. RESULTS: There was a negative correlation between PON1 activity and cystatin C level. Homocysteine level correlated negatively with PON1 activity, and positively with cystatin C level. OxLDL and TBARS levels were significantly higher in the HD and TRX groups compared to C. CONCLUSIONS: Cystatin C may be a good predictive factor not only for homocysteine levels but for the antioxidant status in patients with renal failure and renal transplantation.

Analgesic nephropathy in Hungary: the HANS study.

BACKGROUND: The diagnosis of analgesic nephropathy has improved significantly with modern imaging techniques. We reviewed a large portion of the Hungarian dialysis population to obtain additional insight into the problem. METHODS: Twenty-two participating dialysis units enrolled 1400 patients on renal replacement therapy between 1 January 1995 and 1 January 1998. Patients with no known aetiology (n = 284) were interviewed and studied with renal imaging. We assessed the presence of decreased renal mass combined with either bumpy contours, papillary calcification, or both. The subjects studied were interrogated extensively. RESULTS: Our survey suggested analgesic nephropathy in 47 of 1400 patients (3.3%), 3-fold higher than the EDTA database estimate for Hungary. The analgesics most commonly abused were phenacetin-containing mixtures. The driving symptoms were mainly headache and joint pain. Cardiovascular complications were more common than in the rest of the dialysis population, independent of smoking and lipid values (P<0.01). CONCLUSIONS: Phenacetin should be banned. Our study results support the need for longitudinal cohort and case-control studies in Hungary.

Comparison of dialysis and clinical characteristics of patients with frequent and occasional hemodialysis-associated hypotension.

BACKGROUND: Symptomatic dialysis hypotension (DH) continues to be a common problem. By comparing patients prone and resistant to DH, several dialysis session and patient related characteristics have been identified that confer susceptibility to DH. Less is known, however, about the comparison of patients with frequent and only occasional DH. The aim of the study was to compare clinical and dialysis-session- (complicated by hypotension) related data between those with frequent (fDH) and those with occasional dialysis hypotension (oDH). METHODS: Nine hundred and fifty-eight patients at 11 dialysis units were followed for 10 months and characteristics of patients with fDH (> or = 10 hypotensive events necessitating medical intervention) (n = 96) were compared to that of patients with oDH (1 or 2 events/10 months) (n = 130). Significant and independent predictors of fDH were obtained by multivariate logistic regression. RESULTS: Significant differences between fDH vs. oDH patients were older age (64.4 vs. 56.9 years, p < 0.001), more females (66 vs. 46%, p < 0.005) in fDH. More fDH patients had diabetes (27 vs. 15%, p < 0.05) and less had glomerulonephritis (15 vs. 35%, p < 0.001) as the cause for ESRD. Coronary artery disease (68 vs. 50%, p < 0.01) and long-acting nitrate treatment (51 vs. 30%, p < 0.001) was more frequent while treatment with ACEI (33 vs. 48%, p < 0.05) or Ca-channel blockers (40 vs. 53%, p < 0.05) were less frequent in patients with fDH. Patients with fDH had higher serum phosphorus levels (1.99 vs. 1.79 mmol, p < 0.005). Dialysis session related data were similar but the hypotensive episode occurred earlier during dialysis in fDH (136 vs. 156 min, p < 0.01). In multivariate analysis, significant independent predictors of fDH were older age (OR = 1.04 [1.02-1.07]), lack of glomerulonephritis as renal diagnosis (2.63 [1.18-5.87]), high phosphorus levels (5.0 [2.45-10.0]), lack of use of Ca-channel blockers (2.09 [1.12-3.91]), and the use of nitrates (2.38 [1.24-4.55]). CONCLUSION: Features of the dialysis sessions complicated by DH seem to be similar between patients with fDH and oDH, while patient characteristics such as older age, renal diagnosis other than glomerulonephritis, higher serum phosphorus levels, use of nitrates, and lack of use of calcium channel blockers are significantly and independently associated with fDH.