Predictor factors for renal outcome in renal artery stenosis.

BACKGROUND: Atherosclerotic ischemic renal disease is a frequent cause of end-stage renal failure. Correction of renal artery stenosis (RAS) may fail to stabilize or improve renal function. AIMS OF THE STUDY: Carotid and aortic Intima media thickness (IMT), resistance renal resistance index (RI), arterial blood pressure (BP), serum creatinine (SCr), creatinine clearance (CrCl), proteinuria and uricemia were considered as possible predictive factors and measured before renal-artery stenosis correction and during 12 months follow-up. MATERIALS AND METHODS: we performed an observational study on a total of 55 patients to find predictive factors of the outcome of renal function after renal percutaneous transluminal angioplasty and stenting (RPTAs). RESULTS: We found that uricemia, proteinuria and IR were higher at baseline in patients who worsened renal function after revascularization. CONCLUSIONS: The identification of predictive factors (uricemia; proteinuria and RI) of chronic kidney disease (CKD) progression in patients with RAS undergone revascularization could be useful to predict renal long term outcome and to select patients that really could benefit of this.

Downregulation of cell survival signalling pathways and increased cell damage in hydrogen peroxide-treated human renal proximal tubular cells by alpha-erythropoietin.

OBJECTIVE: Erythropoietin has been shown to have a protective effect in certain models of ischaemia-reperfusion, and in some cases the protection has been correlated with activation of signalling pathways known to play a role in cell survival and proliferation. We have studied whether erythropoietin would overcome direct toxic effects of hydrogen peroxide (H(2)O(2)) treatment to human renal proximal tubular (HK-2) cells. MATERIALS AND METHODS: HK-2 cells were incubated with H(2)O(2) (2 mm) for 2 h with or without erythropoietin at concentrations of 100 and 400 U/ml, and cell viability/proliferation was assessed by chemical reduction of MTT. Changes in phosphorylation state of the kinases Akt, glycogen synthase kinase-3beta (GSK-3beta), mammalian target of rapamycin (mTOR) and extracellular signal-regulated kinase 1 and 2 (ERK1/ERK2) were also analysed. RESULTS: Cells incubated with H(2)O(2) alone showed a significant decrease in viability, which did not significantly change by addition of erythropoietin at concentration of 100 U/ml, but was further reduced when concentration of erythropoietin was increased to 400 U/ml. Phosphorylation state of the kinases Akt, GSK-3beta, mTOR and ERK1/ERK2 of H(2)O(2)-treated HK-2 cells was slightly altered in the presence of erythropoietin at concentration of 100 U/ml, but was significantly less in the presence of erythropoietin at a concentration of 400 U/ml. Phosphorylation of forkhead transcription factor FKHRL1 was diminished in cells incubated with H(2)O(2) and erythropoietin at a concentration of 400 U/ml. CONCLUSIONS: Erythropoietin, at high concentrations, may significantly increase cellular damage in HK-2 cells subjected to oxidative stress, which may be due in part to decrease in activation of important signalling pathways involved in cell survival and/or cell proliferation.

[Nephroangiosclerosis and ischemic nephropathy: two different entities or two renal manifestations of the same systemic cardiovascular disease?]. / La nefroangiosclerosi e la malattia ateromasica ischemica renale: due entita' nosologiche diverse o solo due espressioni renali di una stessa patologia sistemica cardiovascolare?

Nephroangiosclerosis (NAS) is increasingly diagnosed in adult and elderly patients with slowly progressive chronic renal insufficiency. Since these patients usually present with arterial hypertension, this is considered the main cause of NAS (sometimes called, in fact, hypertensive NAS or hypertensive nephropathy). However, there is evidence that other factors such as aging, black race, smoking, and metabolic disturbances contribute to the development and progression of the disease. In some patients, these factors may be prominent while hypertension may be mild or even absent: this form has been denominated ischemic nephropathy (IN). Are NAS and IN really two different diseases or just different presentations of cardiovascular disease involving the kidney? The latter hypothesis is supported by evidence that (a) NAS and IN share a relative aspecificity in their clinical symptoms (low proteinuria, microhematuria, high blood pressure, dyslipidemia) and histopathological features (as determined in the few cases that undergo a kidney biopsy), and (b) there is a high likelihood that atheromatous and hypertensive lesions coexist in the same patient. In this ''Controversy in Nephrology'', Rosario Cianci and Alessandro Zuccala' analyze this issue and try to answer the following questions: 1 - Are NAS and IN two different diseases or two different expressions of the same disease? Rosario Cianci, ''They are two different diseases''. Alessandro Zuccala', ''They represent two different expressions of the same disease''. 2 - Is the pathogenesis different in nephroangiosclerosis and IN? Rosario Cianci, ''The pathogenesis is high blood pressure in NAS and renal ischemia in IN''. Alessandro Zuccala', ''NAS and IN share the same multifactorial pathogenesis: vascular metabolic alterations can cause chronic renal ischemia with or without hypertension''. 3 - Is a biopsy necessary for the diagnosis? Rosario Cianci, ''Yes, it is''. Alessandro Zuccala', ''No, it is not''. 4 - Is it possible to prevent or to slow the progression of the renal damage in this (these) disease(s)? Rosario Cianci, ''Yes it is, by reducing blood pressure''. Alessandro Zuccala', ''Normalization of blood pressure is not enough but all the other risk factors of vascular damage must be addressed, when possible''.

[Multiple peritrochanteric and pubic calcifications in a young woman on hemodialysis with severe renal osteodystrophy successfully treated with sevelamer+cinacalcet+paracalcitol combination therapy]. / Calcificazioni multiple peritrocanteriche e pubiche in giovane emodializzata con grave osteodistrofia renale risolte dall'associazione sevelamer+cinacalcet+paracalcitolo.

Secondary hyperparathyroidism is a frequent complication of chronic renal failure that can induce severe bone disease and negatively influence the cardiovascular outcome. Therefore, nephrologists should attempt to reach the targets recommended by national and international guidelines using all the available therapeutic strategies. We describe the case of a 37-year-old woman affected by spina bifida and myelomeningocele who had been on hemodialysis since 1993. In July 2006 she developed secondary hyperparathyroidism complicated by peritrochanteric calcifications which did not respond to standard therapy. Because it was impossible to perform a parathyroidectomy, we started medical therapy with a combination of sevelamer hydrochloride, paracalcitol and cinacalcet, which resulted in progressive improvement of laboratory data and osteodystrophy. A diagnosis of mixed secondarytertiary hyperparathyroidism was made, but a progressive increase in iPTH to very high levels suggested a rapid evolution toward a pure tertiary form.

Monitoring chronic hemodialysis patients: a questionnaire-based survey.

BACKGROUND: The monitoring program for patients on regular hemodialysis treatment (RDT) is not well defined yet by current international guidelines (CIG). METHODS: To evaluate the extent to which CIG are implemented, we sent a questionnaire to 100 Italian hemodialysis units (DU) with questions concerning: (a) the frequency with which routine tests were performed for the follow-up of patients on RDT; (b) which other non-routine tests were performed. We analyzed the response data and compared them with the CIG. RESULTS: We received 37 replies. We found several differences between the monitoring program of our respondents and the CIG. CONCLUSION: Because of the small number of responses, this survey is only preliminary; however, it shows the difficulty nephrologists have in using the CIG to create a correct monitoring program in patients on RDT. Although our analysis is limited to 37 DUs, it suggests that specific guidelines are necessary to optimize the management of patients on RDT.