Hypertension and nephrology

[Plasma ortho-tyrosine/para-tyrosine ratio predicts hyporesponsiveness to erythropoiesis-stimulating agents in dialyzed patients]

KUN Szilárd1, MIKOLÁS Esztella1, MOLNÁR Gergő Attila1, SÉLLEY Eszter1, LACZY Boglárka1, CSIKY Botond1, KOVÁCS Tibor1, WITTMANN István1

APRIL 10, 2016

Hypertension and nephrology - 2016;20(02)

[Objectives: Patients suffering from end-stage renal failure (ESRF) are mostly treated with erythropoiesis-stimulating agents (ESAs). They often show hyporesponsiveness to ESA, which condition is associated with elevated production of free radicals. Phenylalnine (Phe) is converted into para- and ortho-tyrosine (p- and o- Tyr) by hydroxyl free radical. o-Tyr is produced exclusively in this way. However, physiological isomer p-Tyr is formed in significantly higher amounts by phenylalaninehydroxylase, mainly in the kidney. It has been shown that p-Tyr production is decreased in ESRF. As a result, p-Tyr can be replaced by o-Tyr in proteins, e.g. in proteins playing part in signal transduction of erythropoietin. We aimed to study the association of different Tyr isoforms with ESA-responsiveness. Methods: Four groups of volunteers were involved in our cross-sectional study: healthy volunteers (CONTR; n=16), patients on hemodialysis without ESA-treatment (non-ESA-HD; n=8), hemodialyzed patients with ESA-treatment (ESA-HD; n=40) and patients on continuous peritoneal dialysis (CAPD; n=21). Plasma p-, o-Tyr and Phe levels were detected using a high performance liquid chromatography (HPLC)-method, with fluorescence detection. ESA-demand was expressed as ESA-dose, ESAdose/ body weight and erythropoietin resistance index1 (ERI1, weekly ESA-dose/body weight/hemoglobin). Multivariate regression models were used to examine predictors of ESA-demand. In these models, most of the known predictors of ESA-hyporesponsiveness were included. Results: Lower p-Tyr levels were found in dialyzed patients compared with control subjects. In contrast, o-Tyr levels and o-Tyr/p-Tyr ratios were higher in dialyzed patients. Regarding dialyzed patients, o-Tyr level and o-Tyr/p-Tyr ratio were higher in ESA-HD than in non-ESA-HD and CAPD groups. Weekly ESA-dose/body weight and ERI1 correlated with o-Tyr/p-Tyr ratio (r=0.441, p=0.001; r=0.434, p=0.001, respectively). Finally, o-Tyr/p-Tyr ratio proved to be an independent predictor of ERI1 (β=0.330, p=0.016). Discussion: Our results suggest that elevation of o-Tyr/p-Tyr ratio could be responsible for ESA-hyporesponsiveness in dialyzed patients.]


  1. Pécsi Tudományegyetem, Általános Orvostudományi Kar, II. Sz. Belgyógyászati Klinika és Nephrológiai Centrum, Pécs



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[Blood pressures of adolescents at screening program in Budapest]


[The Aim of the screening program was to investigate the blood pressure and the association with obesity, hypercholesterinaemia and increased body fluid in adolescents. Methods: A screening program was conducted during the period from April 2010 to May 2011.The screenings consisted of: blood pressure, heart rate, body composition determination, cholesterol, blood glucose, weight, height and BMI. Results: 2226 children fullfied all of the outlined criteria. Their range of age was between 14–18 years. The average systolic blood pressure was 126.34±12.55 Hgmm volt. At boys were higher 131.87±13.59 then at girls 117.49±5.69 Hgmm. The average diastolic blood pressure was 71.86±8.74 Hgmm. There were also higher at boys 72.61±9.17 then at girls 66.69±5.04 Hgmm. High systolic blood pressure (95%<) were 307/1326 cases at girls, and 403/876 cases at boys. High diastolic blood pressure were together with high systolic blood pressure, but less frequency. High diastolic blood pressure occurred at 85 girls and at 90 boys. Overweight and obes were 18.994% of girls and 15.26% of boys. The percentage of pathological high blood pressure was most frequent among boys and girls who are in the overweight group. The pathologically high level of body fat percentage appeared to be 12.98% among girls and 5.9% among boys. In elevated BMI groups the frequency of high body fat was 66% among girls and 81% among boys. The mean cholesterol was significantly higher in the overweight and obese group. Conclusions: Rates of hypertension and overweight and obesity are high in school children in Budapest, and increased bodyweight is a significant risk factor for hypertension. The results of the study will help to design preventive programmers.]

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[Rilmenidin - a versatile combination partner in the treatment of high blood pressure]


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[Notes on the management of hypertension in chronic kidney disease ]


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[Recommendation for the treatment of hyperlipidemia in chronic renal disease]


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[Sevelamer: an old-new phosphate binder in chronic kidney disease]


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[The significance of depressive disorders in patients with chronic kidney diseases]

ZALAI Dóra Márta, SZEIFERT Lilla, NOVÁK Márta

[In this article a practice-oriented narrative review of the depressive disorders in chronic kidney disease is provided. Depressive disorders affect approximately one fourth of the chronic kidney disease population. These mental disorders interfere with physical, cognitive and social functioning and are associated with poor prognosis of patients with chronic kidney disease. Bio-psycho-social factors, including immuno-inflammatory processes, disturbance in glucose- insulin homeostasis, sleep disorders, chronic pain, sexual difficulties, changes in social roles, losses in multiple areas of life and low social support increase the risk for the development of depression. Routine, regular screening of depression in the chronic kidney disease population seems to be warranted. Only limited published evidence is available on the therapeutic possibilities of depression in chronic kidney disease. Preliminary evidence indicates that short, structured psychotherapy may be effective for acute treatment and prevention of psychological distress. Some antidepressants can be applied without the need for dose adjustments. On the other hand, some of the psychotropic medications require dose reduction or should be avoided.]