Alexander R Rosenkranz

Dr. Alexander R Rosenkranz

Division of Nephrology, Department of Internal Medicine, Medical University of Graz, 8036 Graz, Austria

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2015 in BMC Nephrology
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EKElisabeth Krones
Elisabeth Krones
Peter FickertPeter Fickert
Peter Fickert
SZSabine Zitta
Sabine Zitta
SNStefan Neunherz
Stefan Neunherz
KAKatharina Artinger
Katharina Artinger
Alexander R RosenkranzAlexander R Rosenkranz
Alexander R Rosenkranz
Accurate measurement of renal function in cirrhotic patients is still challenging. To find the best test for the determination of the true glomerular filtration rate (GFR) in cirrhotic patients this study prospectively compared measured (m)GFR, the gold standard, with estimated (e)GFR using equations based on serum levels of creatinine and cystatin C. GFR was measured by sinistrin clearance using the bolus method in 50 patients with cirrhosis (Child Turcotte Pugh score A, B and C) and 24 age-matched healthy subjects as controls. Measured (m)GFR was compared to eGFR using bias, accuracy 10 % and 30 %, as well as correlation coefficients. Creatinine-based equations generally overestimated GFR in patients with cirrhosis and showed a bias (average difference between mGFR and eGFR) of −40 (CG), −12 (MDRD) and −9 (CKD-EPI-Cr) ml/min/1.73 m2. Cystatin C-based equations underestimated GFR, especially in patients with Child Turcotte Pugh score C (bias 17 ml/min/1.73 m2for CKD-EPI-CysC). Of these equations, the CKD-EPI equation that combines creatinine and cystatin C (CKD-EPI-Cr-CysC) showed a bias of 0.12 ml/min/1.73 m2 as compared to measured GFR. The CKD-EPI equation that combines serum creatinine and cystatin C measurements shows the best performance for accurate estimation of GFR in cirrhosis, especially at advanced stages.

GJGalateja Jordakieva
Galateja Jordakieva
Igor GrabovacIgor Grabovac
Igor Grabovac
Margarete SteinerMargarete Steiner
Margarete Steiner
WWWolfgang Winnicki
Wolfgang Winnicki
SZSabine Zitta
Sabine Zitta
JGJasminka Godnic-Cvar
Jasminka Godnic-Cvar
Kidney transplantation (KTx) in end-stage renal disease is associated with a significant increase in quality of life (QoL) and self-perceived health, optimally leading to the maintenance of employment or return to work (RTW) in working-age patients. The aim of this study was to assess individual factors including the QoL and mental health of kidney transplant recipients (KTRs) associated with employment after transplantation. A cross-sectional study including working-age patients with a history of KTx after 2012 was conducted at two Austrian study centers (Vienna and Graz). Brief Symptom Inventory (BSI-18), World Health Organization Quality of Life (WHOQOL-Bref) and Workability Index (WAI) were assessed along with detailed questionnaires on employment status. Out of n = 139 KTRs (43.2 ± 9.07 years; 57.6% male), 72 (51.8%) were employed. Employed patients were more frequently in a partnership (p = 0.018) and had higher education levels (p = 0.01) and QoL scores (<0.001). Unemployed KTRs reported fatigue and mental health issues more often (p < 0.001), and had significantly higher anxiety, depression and somatization scores (BSI-18). In unadjusted logistical regression, workability score (WAS; odds ratio (OR) = 3.39; 95% confidence interval (CI) = 1.97–5.82; p < 0.001), partnership (OR = 5.47; 95% CI 1.43–20.91; p = 0.013) and no psychological counseling after KTx (OR = 0.06; 95% CI = 0.003–0.969; p = 0.048) were independently associated with employment. Self-assessed mental health, workability and QoL were significantly associated with employment status after KTx. Thus, in order to facilitate RTW after KTx in Austria, vocational rehabilitation and RTW programs addressing KTRs should focus on increasing social support and care for their mental health.

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SASimon Aberger
Simon Aberger
NSNikolaus Schreiber
Nikolaus Schreiber
Stefan PilzStefan Pilz
Stefan Pilz
KEKathrin Eller
Kathrin Eller
Alexander R RosenkranzAlexander R Rosenkranz
Alexander R Rosenkranz
AKAlexander H Kirsch
Alexander H Kirsch
High-dose vitamin D supplementation is common in the general population, but unsupervised high-dose supplementation in vitamin D-replete individuals poses a risk of severe toxicity. Susceptibility to vitamin D toxicity shows a significant inter-individual variability that may in part be explained by genetic predispositions (i.e., CYP24A1 polymorphism). The classic manifestation of vitamin D toxicity is hypercalcemia, which may be refractory to conventional therapy. Its causes include the endogenous overaction of 1α-hydroxylase, monogenic alterations affecting vitamin D metabolizing enzymes and exogenous vitamin D intoxication. In this manuscript, we include a literature review of potential pharmacological interventions targeting calcitriol metabolism to treat vitamin D intoxication and present a case of severe, exogenous vitamin D intoxication responding to systemic corticosteroids after the failure of conventional therapy. Systemic glucocorticoids alleviate acute hypercalcemia by inhibiting enteric calcium absorption and increasing the degradation of vitamin D metabolites but may cause adverse effects. Inhibitors of 1α-hydroxylase (keto/fluconazole) and inducers of CYP3A4 (rifampicin) may be considered steroid-sparing alternatives for the treatment of vitamin D intoxication.

22 July 2013 in BMC Nephrology
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SZSabine Zitta
Sabine Zitta
WSWalter Schrabmair
Walter Schrabmair
GRGilbert Reibnegger
Gilbert Reibnegger
AMAndreas Meinitzer
Andreas Meinitzer
DWDoris Wagner
Doris Wagner
Alexander R RosenkranzAlexander R Rosenkranz
Alexander R Rosenkranz
In renal patients estimation of GFR is routinely done by means of population-based formulae using serum creatinine levels. For GFR determination in the creatinine-blind regions or in cases of reno-hepatic syndrome as well as in critical cases of live kidney donors individualized measurements of GFR (mGFR) employing the kinetics of exogenous filtration markers such as the inulin-like polyfructosan sinistrin are necessary. The goal of this study is to compare mGFR values with the eGFR values gained by the Modification of Diet in Renal Disease (MDRD4) and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) formulae. In 170 subjects comprising persons with normal renal function or with various stages of kidney diseases (CKD 1-4) GFR was measured by application of intravenous bolus of sinistrin and assessment of temporal plasma concentration profiles by means of pharmacokinetic methods (mGFR). Comparisons of mGFR with MDRD4- and CKD-EPI-derived eGFR values were performed by means of linear regression and Bland-Altman analyses. Reasonable agreement of mGFR and eGFR values was observed in patients with poor renal function [GFR below 60 (ml/min)/1.73 m2]. In cases of normal or mildly impaired renal function, GFR determination by MDRD4 or CKD-EPI tends to underestimate GFR. Notably, there is practically no difference between the two eGFR methods. For routine purposes or for epidemiological studies in cases of poor renal function eGFR methods are generally reliable. But in creatinine-blind ranges [GFR above 60 (ml/min)/1.73 m2] eGFR values are unreliable and should be replaced by clinically and physiologically suitable methods for mGFR determination. http://www.consort-statement.org/index.aspx?o=1190

14 April 2021 in Nutrients
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BOBalazs Odler
Balazs Odler
ADAndras T. Deak
Andras T. Deak
GPGudrun Pregartner
Gudrun Pregartner
RRRegina Riedl
Regina Riedl
JBJasmin Bozic
Jasmin Bozic
Alexander R RosenkranzAlexander R Rosenkranz
Alexander R Rosenkranz
Introduction: Magnesium (Mg2+) deficiency is a common finding in the early phase after kidney transplantation (KT) and has been linked to immune dysfunction and infections. Data on the association of hypomagnesemia and the rate of infections in kidney transplant recipients (KTRs) are sparse. Methods: We conducted a single-center retrospective cohort study of KTRs transplanted between 2005 and 2015. Laboratory data, including serum Mg2+ (median time of the Mg2+ measurement from KT: 29 days), rate of infections including mainly urinary tract infections (UTI), and common transplant-related viral infections (CMV, polyoma, EBV) in the early phase after KT were recorded. The primary outcome was the incidence of infections within one year after KT, while secondary outcomes were hospitalization due to infection, incidence rates of long-term (up to two years) infections, and all-cause mortality. Results: We enrolled 376 KTRs of whom 229 patients (60.9%) suffered from Mg2+ deficiency defined as a serum Mg2+ < 0.7 mmol/L. A significantly higher incidence rate of UTIs and viral infections was observed in patients with versus without Mg2+ deficiency during the first year after KT (58.5% vs. 47.6%, p = 0.039 and 69.9% vs. 51.7%, p < 0.001). After adjustment for potential confounders, serum Mg2+ deficiency remained an independent predictor of both UTIs and viral infections (odds ratio (OR): 1.73, 95% CI: 1.04–2.86, p = 0.035 and OR: 2.05, 95% CI: 1.23–3.41, p = 0.006). No group differences according to Mg2+ status in hospitalizations due to infections and infection incidence rates in the 12–24 months post-transplant were observed. In the Cox regression analysis, Mg2+ deficiency was not significantly associated with all-cause mortality (HR: 1.15, 95% CI: 0.70–1.89, p = 0.577). Conclusions: KTRs suffering from Mg2+ deficiency are at increased risk of UTIs and viral infections in the first year after KT. Interventional studies investigating the effect of Mg2+ supplementation on Mg2+ deficiency and viral infections in KTRs are needed.

28 September 2016 in Journal of the American Society of Nephrology
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KEKathrin Eller
Kathrin Eller
Alexander R RosenkranzAlexander R Rosenkranz
Alexander R Rosenkranz