Dávid Ágoston Kovács

Noninvasive Perioperative Monitoring of Arterial Function in Patients With Kidney Transplantation

Development of atherosclerosis is accelerated in kidney transplant recipients. Impaired metabolic pathways have a complex effect on the arterial wall, which can be measured by noninvasive techniques. Few data are available on the change of stiffness parameters in the postoperative course, so in this study we analyzed the stiffness parameters of kidney transplant recipients during the perioperative period. Seventeen successful primary kidney transplant patients with uneventful postoperative period (7 woman, 10 men; 46.16 ± 12.19 years) were involved in our short-term prospective longitudinal study. We analyzed the correlation between noninvasively assessed stiffness parameters (pulse wave velocity [PWV], augmentation index [AIx], pulse pressure [PP], systolic area index, diastolic area index, diastolic reflection area), ankle-brachial index (ABI), and laboratory parameters (creatinine, glomerular filtration rate, urea, haemoglobin, C-reactive protein). Stiffness parameters were measured with a Tensiomed Arteriograph. These parameters were assessed before the transplantation, and 24 hours, and 1 and 2 weeks after surgery under standard conditions. We found that creatinine (P = .0008) and C-reactive protein (P = .006) serum levels decreased, and glomerular filtration rate increased significantly (P = .0005). We revealed that PWV (P = .0075) and AIx (P = .013) improved significantly. There was no significant change in ABI, PP, and the other monitored parameters. Along with the available data in the literature, our findings suggest that kidney transplantation has a positive effect on the arterial function.

A Single-center Experience of Allograft Nephrectomies Following Kidney Transplantation

INTRODUCTION Approximately 10% of renal allografts fail during the first year after kidney transplantation (KT) and 3%-5% thereafter yearly. The indication and timing of allograft nephrectomy (AN) is still uncertain in some cases. The aim of this study was to reveal the ratio, etiology, and complications of AN at our center. MATERIAL AND METHODS This is a retrospective study of all patients who underwent KT at our center between January 1, 2004 and December 31, 2014. We analysed the frequency, indications, timing, and complications of ANs. Also early and late ANs were compared. RESULTS From 417 renal transplantations 49 ANs were performed (11.7%). The most frequent indications were chronic allograft nephropathy (25; 51%), arterial blood supply complications, like arterial thrombosis and stenosis (7; 15%), treatment-resistant acute rejection (3; 6%), and nonreparable ureter complications (3; 6%). The average time of AN since KT was 28 months. ANs were performed as an urgent setting in 16 (33%) cases, whereas it was elective in 33 cases (67%). The AN was executed within 30 days (early) in 11 (22%) cases, and thereafter (late) in 38 (78%) cases. The main indication for early AN was renal artery thrombosis (4; 37%) and chronic allograft nephropathy (25; 66%) for late AN. Surgical complications occurred in 10 cases (20; 4%). The most common was hematoma. CONCLUSION The majority of the ANs were elective and late (more than 30 days; average time, 47 months). Leading indication was chronic allograft nephrectomy. Early ANs were urgent and life-saving in all cases.

Eredményeink a teljes jogú Eurotransplant-tagság óta. A Debreceni Vesetranszplantációs Központ tapasztalatai

Absztrakt Bevezetes: A Debreceni Egyetemen 1991-ben vegeztek el az első veseatultetest. Hazank 2013-ban csatlakozott az Eurotransplanthoz. Celkitűzes: A szerzők elemeztek a tapasztalatokat. Modszer: 2008. januar 1. es 2013. augusztus 31. kozott (A csoport = 163) es 2013. szeptember 1. es 2015. oktober 22. kozott vegzett cadavervese-atultetesek (B csoport = 90) adatait elemeztek. Eredmenyek: Az elődonorok aranya 3,5%-rol 9,1%-ra nőtt. 2013 ota a recipiensek 25%-a 60 evesnel idősebb, a >30 kg/m2 testtomegindex aranya 31%-ra, a diabetesesek aranya ketszeresere emelkedett. Az ureteroneocystostomia mellett bevezetesre kerult a veg az oldalhoz ureteroureteralis anastomosis. Indukcios kezeles mellett az akut rejectios epizod jelentősen csokkent (34%-rol 8%-ra). A technikai szovődmenyek aranya nem valtozott. A bakterialis fertőzesek aranya csokkent (41%-rol 33%-ra). Az 1, 3 es 5 eves veseallograft-tulelesek 86,6%, 85% es 82,7%, valamint 88%, 84% es 84% voltak a ket csoportban. Kovetkeztetesek: Az extended criteri...

Three-Year Longitudinal Clinical Trial of Arterial Function Assessed by a Oscillometric Non-Invasive Method in Comparison With Carotid Sclerosis and Transferrin Kidney-Transplanted Patients

Chronic kidney disease remains one of the main risk factors of cardiovascular disease. However, patients with kidney transplantation have better life expectancy and better quality of life compared with patients on dialysis. In patients with a well-functioning graft, the main cause of death is cardiovascular in origin. Metabolic pathways have complex effects on arterial function that can be monitored by conventional ultrasonography and with the assessment of arterial stiffness by oscillometric non-invasive technique. Forty-one primer cadaver kidney-transplanted patient were involved in a 3-year longitudinal clinical trial (21 female, 20 male; average age, 40.16 ± 12.56 years). Arterial stiffness parameters referring to rigidity of the arterial wall (pulse wave velocity [PWV], augmentation index, and pulse pressure) were investigated. Correlation between stiffness, and laboratory parameters (serum creatinine, urea, hemoglobin, albumin, cholesterine, triglycerides, transferrin, uric acid, glomerular filtration rate, and C-reactive protein) were analyzed. A non-invasive oscillometric method--Tensiomed Arteriograph--was applied to assess the arterial stiffness parameters. Statistical analysis was performed with the use of Statistica for Windows, version 8.0. A value of P < .05 was considered statistically significant for all statistical tests. We found a positive correlation between PWV and left ventricular wall thickness and a negative correlation between PWV and ejection fraction. We also found a positive significant correlation between serum level of transferrin and PWV. There was simultaneous significant progression concerning PWV and carotid artery sclerosis in a 3-year follow-up. There was no fatal cardiovascular event during the study period among our patients. All of our patients involved in this study are still alive. Our findings suggest that arterial stiffness monitoring is a reliable method to assess global cardiovascular risk among kidney-transplanted patients. The oscillometric method is convenient, fast, painless technique to monitor arterial function, which, in the case of pathological findings, proposes more frequent cardiovascular control.

Relationship Between Serum Paraoxonase and Homocysteine Thiolactonase Activity, Adipokines, and Asymmetric Dimethyl Arginine Concentrations in Renal Transplant Patients

Paraoxonase lactonase activity protects against homocysteinylation; therefore, it can be a potential contributing factor to prevent atherosclerosis. We aimed to determine paraoxonase and HTLase activities and to clarify the relationship between HTLase activity and some cardiovascular risk factors, such as homocysteine, cystatin C asymmetric dimethylarginine (ADMA), and adipokines both in hemo dialyzed and transplanted patients. Among 114 hemodialyzed, 80 transplanted and 64 healthy control subjects, we investigated body mass index (BMI) as well as fasting serum contents of urea, uric acid, creatinine, cystatin C, homocysteine, glucose, lipids, total protein and albumin. Serum paraoxonase (PON 1) and HTLase activities were measured spectrophotometrically. ADMA, ADPN adiponectin, leptin (LEP) levels was determined with a sandwich enzyme-linked immunosorbent assay method. Dyslipidemic patients showed hypercholesterolemia, and high low-density lipoprotein (LDL); parallel with improved renal function, they displayed decreased cystatin C and homocysteine levels (P < .001). There was a significant negative correlation between PON 1 activity and cystatin C and homocysteine concentrations (P < .05). Obese patients revealed significantly higher LDL (P < .05) and leptin concentrations (P < .01). There was a significant positive correlation between PON 1 activity and adiponectin levels (P = .0276). Both dialyzed and transplanted patients displayed significantly lower HTLase activities compared to the control group (P < .001), particularly lower HTLase and PON 1 activities in dialyzed subjects compared with the transplanted group (P < .05). HTLase activity showed significant negative correlations with ADMA levels among the whole study population (P < .001), whereas positive associations were noted between PON 1 and HTLase activities (P < .001). HTLase activity may be a new predictor of cardiovascular risk in renal failure although it is modulated by other risk factors.

Prospective study of changes in arterial stiffness among kidney-transplanted patients.

BACKGROUND Chronic kidney disease is one of the main risk factors for cardiovascular disease. Changes in stiffness parameters can predict the higher risk of the development of cardiovascular disease. METHODS Cadaveric donor kidney transplant patients (n=184) were followed in a cross-sectional single-center study. Arterial stiffness parameters were measured by arteriography. We analyzed the correlation between stiffness parameters and immunosuppressive therapy, the main operation parameters, patient age, elapsed time since transplantation, carotid artery stenosis, and septual wall thickness. We enrolled 24 patients in a 3-year longitudinal study to analyze changes in stiffness parameters. RESULTS Our cross-sectional study showed pulse wave velocity (PWV) to be significantly related to the age of the patient (P=.0001; r=0.41). There was no significant correlation between the stiffness parameters and type or dosage of immunosuppressive drugs and number of transplantations. We noted significant correlations between pulse pressure (PP) and pulse wave velocity (PWV), and augmentation index (AI) (P=.01). Patients with abnormal PWV (>12 m/s) showed significantly higher systolic blood pressures, body mass indexes, PP, and AI (P<.01). Our 3-year longitudinal study revealed a significant elevation in PWV. CONCLUSIONS Improving endothelial function and prevention of atherosclerosis may help to reduce cardiovascular complications. Among chronic kidney disease patients, early transplantation is a possible way to prevent cardiovascular events. It is better to perform the transplantation at as early an age as possible.

Pregnancy management of women with kidney transplantation.

Women with renal disease, besides many dysfunctions, face increasing infertility and high-risk pregnancy due to uremia and changes of the hormonal functions. After renal transplantation, sexual dysfunction improves, providing the possibility of successful pregnancy for women of childbearing age. However, kidney transplanted patients are high-risk pregnant patients with increased maternal and fetal risks, and the graft also may be compromised during pregnancy; most studies report on several successive deliveries due to multidisciplinary team management. In clinical practice, the graft is rarely affected during the period of gestation. Fetal development disorders are also rare although preterm delivery and intrauterine growth retardation are common. For now, several studies and clinical investigations proved that, under multidisciplinary control, kidney transplanted female patients are also possible to have safe pregnancy and successful delivery. There are conflicting data in the literature about the prevention of complications and the timing of pregnancy. Herein, we would like to present some experience of our centre. A total of 847 kidney transplantations have been performed between June 1993 and December 2013 with 163 childbearing aged females (18-45 years) in our center. We report on three kidney transplanted patients who have given birth to healthy newborns. In our practice, severe complications have not been observed.

Az angiotenzinkonvertálóenzim-gén I/D polimorfizmusának hatása a vesetranszplantált betegek cardiovascularis rizikójára és a grafttúlélésre

Absztrakt Bevezetes: A vegstadiumu vesebetegsegben szenvedők kezeleseben a veseatultetes hosszabb tulelest biztosit, mint a vesepotlo kezelesek egyeb formai. A recipiens varhato tuleleset leginkabb a magasabb sziv-er rendszeri eredetű halalozas befolyasolja. A transzplantalt vese karosodasanak leggyakoribb oka az idult allograft-nephropathia. Celkitűzes: A szerzők a recipiens es a beultetett vese hosszu tavu tulelesevel egyertelmű osszefuggest mutato biomarkerek azonositasat tűztek ki celul. Modszer: A retrospektiv vizsgalatba 72 beteget vontak be. Meghataroztak az angiotenzinkonvertaloenzim-gen I/D polimorfizmusat, az enzim aktivitasat, a vesefunkciot, valamint a sziv morfologiai jellemzőit. Eredmenyek: Az angiotenzinkonvertaloenzim-gen DD genotipusa egyarant osszefuggest mutatott az idult allograft-nephropathia es a sulyos foku bal kamrai hypertrophia előfordulasaval. A vesefunkcio es a szivizom-hypertrophia merteke kozott szoros osszefuggest talaltak. Kovetkeztetesek: Eredmenyeik szerint az angiotenzin...

Graftectomiák a debreceni vesetranszplantációs programban

Absztrakt Bevezetes: A graftectomia indikacioja es pontos időzitese bizonyos esetekben vita targya, elsősorban a tuneteket nem okozo, mar nem műkodő graftok eseten. Celkitűzes: A szerzők atfogo kepet kivantak adni a debreceni veseatultetesi programban elvegzett graftectomiakrol. Modszer: Retrospektiv vizsgalattal elemeztek a 2004. januar 1. es 2015. december 31. kozott veseatultetett betegek adatait. Attekintettek a graftectomiak indikacioit, időziteset, szovődmenyeit, tovabba osszehasonlitottak a korai es kesői graftectomiakat. Eredmenyek: A vizsgalt időszakban 480 veseatultetes tortent. Kozuluk 55 betegnel (11%) tortent graftectomia. A gyakoribb indikaciok a kovetkezők voltak: kronikus allograft-nephropathia (47%), arterias keringesi zavar (13%), ureterszovődmenyek (9%). A grafteltavolitas 22 betegnel (40%) akut, 33-nal (60%) tervezett volt. A graftectomiak 24%-a a transzplantacio utan 30 napon beluli, 76%-a kesői volt. Korai graftectomiat tulnyomoreszt arterias keringeszavar (31%), a kesőiek tobbseget ...

Donorszelekciós kritériumok vizsgálata a debreceni veseátültetési programban

Absztrakt Bevezetes: A donorszervhiany, a donorok eletkoranak novekedese es a tarsbetegsegek gyakoribba valasa arra osztonzi a transzplantalokozpontokat, hogy olyan donorvesek elfogadasat is merlegeljek, amelyeket korabban elutasitottak volna. A donorszelekcios kriteriumok segithetnek ennek eldonteseben. Celkitűzes: A kulonboző kriteriumok hasznossagat illetően nincs egyseges allaspont, ezert a szerzők megvizsgaltak az expanded criteria donor, a deceased donor score es a kidney donor risk index donorszelekcios kriteriumok hatasat a posztoperativ vesefunkciora es grafttulelesre. Modszer: Oteves intervallumban 205 donor parametereinek es 138 veseatultetes kimenetelenek retrospektiv elemzeset vegeztek el. Eredmenyek: Az expanded criteria donor rendszer szerint optimalisnak velemenyezett donorok negyede a magas kockazatu csoportba kerult a deceased donor score alapjan. A magas kockazatu csoportokban rosszabb volt a műtet utani graftfunkcio. A deceased donor score segitsegevel tovabb lehetett bontani a magas k...