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.]

AFFILIATIONS

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

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Hypertension and nephrology

[Blood pressures of adolescents at screening program in Budapest]

KORMOS-TASI Judit, GÁCSI Erika, SCHEURING Noémi, TÓTH Fanni, CZINNER Antal, SZABÓ László

[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.]

Hypertension and nephrology

[Initiation of antihipertensive therapy with fix combinations, focusing on perindopril, amlodipine and indapamide]

FARSANG Csaba

[Early clinical studies proved that most hypertensive patients (>70%) need drug combinations to reach the target blood pressure. We should combine two or three - sometimes more - drugs from different antihypertensive classes for quicker normalisation of blood pressure and to reduce incidence and severity of hypertensive complications. Several international and Hungarian (MHT 2015) guidelines emphasize the advantages of fix combinations against free combinations. Most frequently used combinations contain ACEi + calcium antagonist, or ACEi + diuretic. From them I will focus on the perindopril + amlodipine or perindopril + indapamide combinations. If we do not reach target blood pressure, triple fix combinations (e.g. perindopril + amlodipine + indapamide) can also be used. Now there are fix combinations of different strengths, therefore we may start the therapy with these fix combinations according to patients’ characteristics (e.g. age, complications, concomitant diseases).]

Hypertension and nephrology

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

KÉKES Ede

[The rilmenidin as an imidazoline agonist drug strongly decreases the central sympathetic activity, release of renine and the RAS activity. Because of these advantageous properties the peripheral vascular resistance falls and the blood pressure is decreased. Today it is excellent tool for combination therapy. Useful especially in stress induced hypertension. The antihypertensive effects of ACE inhibitors sor calcium antagonists are increased by rilmenidine. This drug decreases the insuline resistance, it has a positive effect on the carbohydrate and fat metabolism, because it is useful as a complementary therapy in metabolic syndrome and diabetes mellitus of type II. It is useful in stress induced hypertension, and in menopause as well.]

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Risk factors for ischemic stroke and stroke subtypes in patients with chronic kidney disease

GÜLER Siber, NAKUS Engin, UTKU Ufuk

Background - The aim of this study was to compare ischemic stroke subtypes with the effects of risk factors, the relationship between grades of kidney disease and the severity of stroke subtypes. Methods - The current study was designed retrospectively and performed with data of patients who were hospitalised due to ischemic stroke. We included 198 subjects who were diagnosed with ischemic stroke of Grade 3 and above with chronic kidney disease. Results - In our study were reported advanced age, coronary artery disease, moderate kidney disease as the most frequent risk factors for cardioembolic etiology. Hypertension, hyperlipidemia, smoking and alcohol consumption were the most frequent risk factors for large-artery disease. Female sex and anaemia were the most frequent risk factors for small-vessel disease. Dialysis and severe kidney disease were the most frequent risk factors in unknown etiologies, while male sex, diabetes mellitus, prior stroke and mild kidney disease were the most frequent risk factors for other etiologies. National Institute of Health Stroke Scale (NIHSS) scores were lower for small-vessel disease compared with other etiologies. This relation was statistically significant (p=0.002). Conclusion - In order to improve the prognosis in ischemic stroke with chronic kidney disease, the risk factors have to be recognised and the treatment options must be modified according to those risk factors.

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

AMBRUS Csaba

[The prevalence of hypertension among pa­tients with chronic kidney disease is high, reaching more than 80%. Hypertension is both one of the main causes and also the most common consequence of chronic kidney disease. It is also a main factor responsible for the high cardiovascular morbidity and mortality in this patient population. Blood pressure control can improve patient outcomes, lower cardiovascular risk and slow down the progression of kidney dis­ease, irrespective of the underlying cause. The optimal therapy should therefore focus not only on blood pressure reduction but also on renoprotection. Basic understanding of the renal pathophysiology in hypertension and renal effects of various medications is of paramount importance. In this review, we summarized cornerstones of the antihypertensive therapy in patients with chronic kidney disease. The management of patients receiving kidney replacement therapies, such as hemodialysis, peritoneal dialysis or transplanta­tion requires special knowledge and expe­rience, therefore it is not discussed here. The aim of this review was to allow non-nephrologist physicians to take care of their kidney patients with more confidence and effectiveness.]

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

MÁTYUS János, PARAGH György

[The incidence of chronic kidney disease continuously increases worldwide. Studies suggest that kidney disease is an as powerful cardiovascular risk factor as diabetes mellitus. Because of the high prevalence of lipid disorders, it is likely that dyslipidaemia plays a major role in the high cardiovascular risk of these patients. Evidence supports treating dyslipidaemia in patients with mild or moderate kidney disease, but the results of statin trials in dialysed patients are inconclusive. A practical treatment algorithm is proposed considering the special aspects, the effectiveness and safety of the drugs in the whole spectrum of kidney disease.]

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

BERECZKI Csaba, TÚRI Sándor

[Sevelamer HCl is a non-metal and non-calcium based phosphate binder, ion exchange resin, which not selectively binds the phosphate ions in the gastrointestinal tract. In Hungary since 2005, on the basis of strict professional guidelines, sevelamer is available therapy for chronic kidney disease patients with severe hyperphosphatemia on dialysis. On the basis of 17 prospective and retrospective studies, sevelamer HCl is an at least as effective phosphate binder as other calcium based binders, in reducing the serum phosphate level. The advantage of sevelamer compared to the other widely used calcium based phosphate binders is the significantly lower serum calcium level and less hypercalcemic episodes. Sevelamer therapy in chronic kidney disease patients reduces the progression of cardiovascular calcification and it has also a positive effect on cholesterol and LDL-cholesterol levels. The side effects of sevelamer therapy may be acidosis, and gastrointestinal complaints. This year the improved form, sevelamer carbonate, becomes available in Hungary. Sevelamer carbonate has similar phosphate and cholesterol binding capacity as that of sevelamer HCl, but it has several advantages: it has a positive effect on acid-base parameters, and may be administered in powder form, which is beneficial for children and for patients with swallowing disorders. The primary analysis of the DCOR study has not revealed any significant difference in the survival and cardiovascular mortality between patient groups treated with calcium based binder or sevelamer. The RIND trial data showed improved survival of new dialysis patients, who were initially treated with sevelamer. Further clinical studies are needed to kaverify the benefits of sevelamer therapy (mortality, cardiovascular calcification) in chronic kidney disease patients. The management of hyperphosphatemia in chronic renal failure is a major challenge even in the first decade of the 21th century. This is the fact, despite that recently three different groups of phosphate binders are available in the clinical practice: the calcium based binders (calcium carbonate, calcium acetate), sevelamer and lanthanum. Which is the best binder? A calcium based or a non-calcium based one? Over the past decade, these issues are in the mainstream of clinical research of nephrology.]

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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.]