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What is Malignant hypertension ?

Malignant hypertension and accelerated hypertension are both hypertensive emergencies, both of them have similar outcomes and therapies. Malignant hypertension may or may not be associated with clinical signs and symptoms present in hypertensive urgency. A patient is said to have malignant hypertension when he or she has retinal papilledema as well as flame-shaped hemorrhages and exudates. 
More modern definition for malignant hypertension,states that this is a hypertensive emergencies, in the absence of retinopathy, be based on the criteria of acute elevated blood pressure accompanied by damage to a minimum of three different target organs.
Other clinical features of malignant hypertension may include the following 
  • Encephalopathy 
  • Confusion 
  • Left ventricular failure 
  • Intravascular coagulation 
  • Impaired renal function, with hematuria 
  • Weight loss.
About 1% of patients with essential hypertension may develop malignant hypertension, but the reason why some patients develop malignant hypertension is unknown.
What is the pathologic hallmark of malignant hypertension?
The pathologic hallmark of malignant hypertension is fibrinoid necrosis of the arteriole, eventhough it occurs systemically, but specifically seen in the kidneys. These patients develop fatal complications if untreated, and more than 90% will not survive beyond 1-2 years.. 
Red blood cells are damaged when they flow through thse vessels that are obstructed by fibrin deposition, resulting in microangiopathic hemolytic anemia
What are the causes of malignant hypertension?
  • Any form of secondary hypertension; 
  • Complications of pregnancy
  • Renal artery stenosis
  • Pheochromocytoma
  • Aortic coarctation 
  • Hyperaldosteronism is also a secondary cause of hypertension
  • Both hyperthyroidism and hypothyroidism can cause hypertension.
  • Use of cocaine
  • Monoamine oxidase inhibitors (MAOIs)
  • Oral contraceptives
  • Withdrawal of alcohol, beta-blockers, or alpha-stimulants. 
Other conditions that should be excluded are 
  • Stroke
  • Intracranial mass
  • Head injury 
  • Epilepsy 
  • Postictal state 
  • Connective-tissue disease (especially lupus with cerebral vasculitis)
  • Drug overdose or withdrawal, cocaine or amphetamine ingestion
  • A anxiety
  • Thrombotic thrombocytopenic purpura.