(BQ) Part 2 book "Fundamentals of renal pathology" presentation of content: Vascular diseases, tubulointerstitial diseases, plasma cell dyscrasiasand associated renal diseases, renal transplant pathology. | Part V Vascular Diseases Nephrosclerosis and Hypertension 10 Arterionephrosclerosis Introduction/Clinical Setting Approximately 60 million people in the United States have hypertension. Many are undiagnosed or untreated. Different populations have different risks and different consequences of hypertension. Increased hypertension is seen with aging, positive family history, African-American race, and exogenous factors such as smoking. Although African-Americans make up only 12 % of the US population, they are fivefold overrepresented among patients with end-stage renal disease (ESRD) presumed due to hypertension [1, 2]. Hypertension is associated with significant morbidity and mortality due both to cardiovascular and renal diseases [1–5]. Essential hypertension is diagnosed when no cause is found. Hypertension may also be secondary to various hormonal abnormalities, including excess aldosterone, norepinephrine, or epinephrine, or produced from adrenal cortical, medullary, or other tumors; renin-producing tumors; or hypercalcemia or hyperparathyroidism. Other secondary causes include neurogenic, iatrogenic, and structural lesions (., coarctation of the aorta). Renal hypertension refers to hypertension secondary to renal disease. Chronic renal disease is the most common form of secondary hypertension (5–6 % of all hypertension). The kidneys modulate blood pressure in several ways: They modulate salt/water balance under the influence of aldosterone. The kidney is also a major site of renin production, which allows generation of angiotensin II, an important vasoconstrictor and stimulus for aldosterone secretion. In renovascular disease (., stenosis of the renal artery), renal ischemia is thought to be the stimulus that increases renin-angiotensin system activity, thereby increasing systemic blood pressure. In renal parenchymal disease, multiple factors contribute to increased blood pressure. The decreased mass of functioning nephrons leads to a decrease in .
