Definition and Causes of Hypertension

 

  HYPERTENSİON

  Hypertension is characterizied by elevation in blood pressure. There are 2 types of hypertesion. One with no diagnostic reason called essential hypertesion.Of all hypertesion cases 80-95% is called essential hypertension.The other type is called as secondary hypertesion.This type has a causative effect.Before aged 30 or after aged 55 with the new onset of hypertesion we should look for a secondary cause another say secondary hypertesion.

  SECONDARY HYPERTESİON

  RENAL ARTERY STENOSİS

  Renal artery stenosis can be caused by either atherosclerosis or fibromuscular dysplasia.Athero sclerosis is mostly seen in older men, on the other hand fibromuscular dysplasia is mostly seen in young women.Renin angiotensin aldosteron system activation cause the hypertesion.

  RENAL PARENCHYMAL DİSEASE

  There will be an abormality in urine anlayses.This cause some certain blood incredients increase such as creatinin.

  COARCTATİON OF AORTA

  Coarctation is usually seen in aorta at the level of left subclavian artery. This causes delayed and diminished pulse in femoral artery. Doppler echocardiography shows the region of coarctation.

                              

  PHEOCHROMACYTOMA

  Pheochromacytoma is a tumor that causes the realese of catecholamine.It is usually seen in adrenal medulla or extraadrenal paraganglion tissue.The symptoms of pheochromacytoma are palpitation headache and diaphoresis. Other symptoms are      glucose intolerance, wight lost and orthostatic hypotension.Pheochromacytome may also seen on bladder wall. We may see elevated plasma metaphanephrine level or urinary catecholamine in 24 hours urine sample.İf we see that than we order CT or MRI to localize the tumor.

  HYPERALDOSTERONİSM

  Hyperaldosteronism is caused by tumors that are aldosterone secreting adenoma or bilateral adrenal hyperplasia.Hypokalemia(low blood potassium level) is seen on disease progression.Refractory hypertension is present in hyperaldosteronism.

  OTHER CAUSES

  -Obstructive sleep apnea syndrome(OSAS)

  -Oral contraceptives

  -Thyroid disease

  -Cushing’s syndrome

  -Hypercalcemia

  -Acromegaly

  APROACH TO THE PATİENT

  However most patients show no symptoms, in severe cases headache, dizziness and blured vision may seen.

  We should have a detailed patients history fort the diagnosis of secondary hypertasion.

  Like other diseases we should make a ohysical examination for certain patterns.Measureing blood pressure in both arms and both legs(aortic coarcitation). Cushingoid appearance, thyromegaly, abdominal bruits(renal artery stenosis), and delayed femoral pulse(aorta coarctation) are the signs of secondary hypertesion.

  Labaratory:Serume creatinine, BUN, urinalysis, serum K+ measures, CXR, ECG, CBC, glucose, lipid levels, calcium, uric acid, TSH.

  Specific workup:Cushingoid syndrome; dexamethasone suppression test, renal artery stenosis; captopiril radionuclide scan, renal duplex USG, magnetic resonance angiography, pheochromacytoma; 24 h urine collection for cathecolamines, metanephrines and vanillymandelic acid(VMA), primary hyperaldosteronism; deppresed plasma renin activity and hypersecretion of aldosterone,   renalparenchymal disease.

  Best wishes...

  Dr. Rıdvan