Common Causes of Secondary Hypertension






1. Genetic causes
  • Hypertension can be caused by mutations in single genes.
  • Liddle syndrome is an autosomal dominant condition characterized by early-onset hypertension, hypokalemic alkalosis, low renin and low aldosterone levels.

2. Renal disease
  • Renal parenchymal disease is the most common cause of secondary hypertension. 
  • Mechanisms : related to increased intravascular volume or increased activity of the renin–angiotensin–aldosterone system.

3. Renal vascular hypertension
  • Due to atherosclerotic stenoses of the renal arteries.
  • Mechanisms : relate to excessive renin release due to reduction in renal perfusion pressure and attenuation of pressure natriuresis with stenosis affecting a single kidney or with bilateral renal artery stenosis.
  • Renal vascular hypertension should be suspected in the following circumstances:
    • (1) if the documented onset is before age 20 or after age 50 years.
    • (2) hypertension is resistant to three or more drugs.
    • (3) if there are epigastric or renal artery bruits.
    • (4) if there is atherosclerotic disease of the aorta or peripheral arteries.
    • (5) if there is an abrupt increase (> 25%) in the level of serum creatinine after administration of ACE inhibitors.
    • (6) if episodes of pulmonary edema are associated with abrupt surges in blood pressure.

4. Primary hyperaldosteronism
  • The lesion responsible for hyperaldosteronism is an adrenal adenoma or bilateral adrenal hyperplasia and can be demonstrated by CT or MRI scanning.

5. Cushing syndrome
  • Excess glucocorticoid may induce salt and water retention through mineralocorticoid effects.

6. Pheochromocytoma
  • The blood pressure elevation caused by the catecholamine excess results mainly from α-receptor-mediated vasoconstriction of arterioles, with a contribution from β1-receptor-mediated increases in cardiac output and renin release.

7. Coarctation of the aorta

8. Hypertension associated with pregnancy
  • preeclampsia
  • eclampsia

9. Estrogen use
  • A small increase in blood pressure occurs in most women taking oral contraceptives, mostly in obese older than age 35 who have been treated for more than 5 years.

10. Other causes of secondary hypertension
  • hypercalcemia
  • acromegaly
  • hyperthyroidism
  • hypothyroidism
  • baroreceptor denervation
  • compression of the rostral ventrolateral medulla
  • increased intracranial pressure

A number of medications may cause or exacerbate hypertension:
  • cyclosporine
  • tacrolimus
  • angiogenesis inhibitors
  • decongestants
  • NSAID

Source: CMDT 2013
 

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