[Nephroangiosclerosis and ischemic nephropathy: two different entities or two renal manifestations of the same...

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''.