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The increased prevalence of chronic kidney disease (CKD) in elderly patients recognizes, as main cause, the long-term exposure to atherosclerosis and hypertension. Chronic ischemic damage due to critical renal arterial stenosis induces oxidative stress and intra-renal inflammation, resulting in fibrosis and microvascular remodelling, that is the histological picture of atherosclerotic renal vascular disease (ARVD). The concomitant presence of a long history of hypertension may generate intimal thickening and luminal narrowing of renal arteries and arterioles, glomerulosclerosis, interstitial fibrosis and tubular atrophy, more typically expression of hypertensive nephropathy. These complex mechanisms contribute to the development of CKD and the progression to End Stage Kidney Disease. In elderly CKD patients, the distinction among these nephropathies may be problematic; therefore, ischemic and hypertensive nephropathies can be joined in a unique clinical syndrome defined as atherosclerotic nephropathy. The availability of novel diagnostic procedures, such as intra-vascular ultrasound and BOLD-MRI, in addition to traditional imaging, have opened new scenarios, because these tools allow to identify ischemic lesions responsive to renal revascularization. Indeed, although trials have deflated the role of renal revascularization on the renal outcomes, it should be still used to avoid dialysis initiation and/or to reduce blood pressure in selected elderly patients at high risk. Nonetheless, lifestyle modifications (smoking cessation, increased physical activity), statins and antiplatelet use, as well as cautious use of renin-angiotensin system inhibitors, remain the main therapeutic approach aimed at slowing the renal damage progression. Mesenchymal stem cells and Micro-RNA are promising target of anti-fibrotic therapy, which might provide potential benefit in ARVD patients, though safety and efficacy profile in humans is unknown too.

Bone mineral abnormalities (defined as Chronic Kidney Disease Mineral Bone Disorder; CKD-MBD) are prevalent and associated with a substantial risk burden and poor prognosis in CKD population. Several lines of evidence support the notion that a large proportion of patients receiving maintenance dialysis experience a suboptimal biochemical control of CKD-MBD. Although no study has ever demonstrated conclusively that CKD-MBD control is associated with improved survival, an expanding therapeutic armamentarium is available to correct bone mineral abnormalities. In this position paper of Lombardy Nephrologists, a summary of the state of art of CKD-MBD as well as a summary of the unmet clinical needs will be provided. Furthermore, this position paper will focus on the potential and drawbacks of a new injectable calcimimetic, etelcalcetide, a drug available in Italy since few months ago.

Vascular accesses are essential for effective dialysis treatment. Arteriovenous fistulas, grafts and central venous catheters are the options available to the nephrologist, but they all have their pros and cons. All of the 3 types of vascular access share the same complications but at different rates, and their costs vary enormously, with on balance the arteriovenous fistula being the best choice. Nevertheless, recently the number of incident patients starting dialysis treatment with a venous catheter as vascular access has been steadily increasing. This is true even for more advanced countries such as the United States, where despite the efforts made to promote the use of fistulas, their prevalence is still low compared with Europe. Moreover, nowadays nephrologists are required to master technical skills that once were those of surgeons and to perform interventions to preserve the patency of the access. The aim of this paper is to review the prevalence, benefits and complications of the different vascular accesses in light of the most recent findings.

Background: Cardiovascular disease (CVD) is the leading cause of death in Western countries and is highly prevalent in patients with kidney disease. Traditional risk factors for CVD often accompany kidney dysfunction, and chronic kidney disease per se is considered an additional risk factor. Risk stratification for CVD remains suboptimal even after the introduction of global risk assessment by various scores. This has prompted the search for novel markers of cardiovascular risk, and several biomarkers have been suggested as candidates, together with C-reactive protein (CRP). The objective of the present study was to investigate the relationship between novel biomarkers of vascular inflammation (soluble form of the receptor for advanced glycation end products [sRAGE] and eotaxin-3) with CRP in a population of hypertensive patients at high cardiovascular risk. Methods: Plasma sRAGE, high-sensitivity CRP (hs- CRP) and eotaxin-3 were measured in 399 hypertensive patients (265 men, mean age 58 ± 8 years)with diabetes mellitus, metabolic syndrome or organ damage. Results: Plasma concentrations of sRAGE, eotaxin-3 and hs-CRP were not different between diabetic and nondiabetic subjects. Univariate analysis showed that plasma levels of sRAGE and eotaxin-3 were not associated with hs-CRP in either subgroup. Conclusion: Our study confirms the robust and widely studied role of CRP as an important marker of vascular inflammation. We also postulate the possible involvement of sRAGE and eotaxin, 2 novel biomarkers, in CVDs. On the basis of our results, we can put forward the hypotheses that hs-CRP, s-RAGE and eotaxin are reliable but unrelated cardiovascular risk markers. © 2012 Società Italiana di Nefrologia - ISSN 1121-8428.

The aging process results in remarkable changes in the kidney. These changes are both anatomical and functional and have been considered the cause of the increased propensity of the elderly to acute or chronic renal failure. However, the majority of the early studies on aging enrolled institutionalized elderly patients with several comorbidities such as hypertension and heart disease which could by themselves induce renal alterations. Recently the selection of subjects lacking renal disease or processes known to affect renal function has demonstrated that aging changes are less pronounced in healthy aged subjects. Nonetheless, understanding aging-induced renal changes may help to prevent life-threatening kidney disease. This review will focus on glomerular hemodynamics, and on renal sodium and potassium handling and diluting and concentrating ability.

Aging is characterized by a decline in renal function and by a susceptibility to renal diseases. However it is not clear whether the observed changes are solely hemodynamic, structural or both. We evaluated renal function, functional reserve (RFR) and morphology in healthy elderly individuals.Healthy participants (n=19) were divided into young (n=6, age range 25-37 years), middle-aged (n=6, 44-74 years) and elderly (n=7, 81-96 years). Nitric oxide (NO), plasma renin activity (PRA) and aldosterone, renal plasma flow (RPF) by p-aminohippurate clearance (CPAH) and glomerular filtration rate (GFR) by inulin clearance (CIN) were determined before and during maximal vasodilating stimuli, induced with the infusion of dopamine and amino acids. Glomerular sclerosis, lumen area and wall thickness of afferent arterioles were determined by kidney biopsy from 36 healthy kidney donors and from 6 nephrectomies for renal carcinoma.GFR and RPF were slightly reduced in elderly individuals whereas filtration fraction (FF) was increased. GFR and RPF did not increase in the elderly after maximal vasodilating stimuli as in young and middle-aged subjects suggesting a reduction of RFR. NO, increased at baseline, did not increase further after vasodilating stimuli; while on the contrary, PRA, similar in the 3 groups at baseline, was not reduced by vasodilating stimuli in the elderly. Sclerotic glomeruli but not glomerular volume were significantly increased by aging. Afferent arteriole lumens were reduced by aging whereas wall thickness was unchanged.Renal function is preserved with aging in healthy subjects at the expense of a complete reduction of RFR. RFR may be wasted to compensate for the increased number of sclerotic glomeruli. Vascular changes, suggested by reduced arteriolar lumen, may be so advanced that even in the presence of high levels of vasodilatory molecules, kidneys are not responsive anymore to maximal vasoactive stimuli.

Cardiovascular complications are the main cause of death in uremic patients. Uremic angiopathy has been regarded as an accelerated form of atherosclerosis. However the mechanism leading to vessel wall injury is still unknown. We hypothesized that uremic serum affects endothelium inducing a proatherogenic state.We studied the effects of uremic serum on human endothelial cells (HECs). Cell proliferation and adhesion of mononuclear cells to HEC monolayers were evaluated by cell counting, apoptosis and collagen production by ELISA, and nitric oxide (NO) by measuring the concentration of nitrite/nitrate in the cell supernatant. (alfa2)IV collagen, tissue inhibitor of metalloproteases-1 (TIMP-1) and transforming growth factor-beta (TGF-beta) mRNA levels were measured by reverse transcriptase polymerase chain reaction (RT-PCR). In some experiments cells were preincubated with anti-receptor for advanced glycation end product (anti-RAGE) blocking antibodies.Uremic serum did not modify HEC proliferation but induced apoptosis after 72 hours of incubation. Adhesion of mononuclear cells to HEC monolayers was significantly increased by uremic serum. In addition, uremic serum increased (alfa2)IV collagen, TIMP-1 and TGF-beta mRNA levels. There was no increase in nitric oxide concentration in ure-mic serum-treated endothelial cells, and the expression of TGF-beta was neither modified by L-NAME nor by anti-RAGE antibodies.Our results indicate that uremic serum affects HEC inducing a proatherogenic state that may be responsible for the accelerated atherosclerosis of uremic patients. Apparently uremic serum effect is not mediated by NO or by AGEs.