Renal artery stenosis : Causes, Symptoms, Daignosis and Treatment

Renal artery stenosis is the narrowing of the one or more arteries that carry blood to the kidneys. It prevents the normal amounts of oxygen-rich blood to reach the kidneys.

• It is mostly seen id order people with atherosclerosis (hardening of the artery)
• Over time it can get worse, which can lead to high blood pressure (hypertension) and then to kidney damage or failure.

Causes of renal artery stenosis:

There may be two main causes of stenosis:

• Atherosclerosis of the renal arteries: Atherosclerosis is the bulid up of fats and other deposits in the artery walls, as the deposits gets larger, they  can harden, reduce blood flow and cause scarring of the kidney. Which can further cause narrowing of the artery and stenosis
• Fibromuscular dysplasia: In this case, the muscles of the artery walls grows abnormally. It can cause the renal artery to narrow so much that kidneys doesn’t get adequate supply of blood and can become damaged.

Other rare causes can be:

• Inflammation of blood vessels
• Neurofibromatosis (a nervous system disorder that cause tumours to develop in nerve tissues)

Risk factors of renal artery stenosis:

Certain risk factors may include:

• Aging
• High blood pressure
• High cholesterol
• Diabetes
• Obesity
• Smoking or other tobacco use
• Family history of kidney diseases

Symptoms of renal artery stenosis:

Renal artery stenosis usually have no symptoms or signs. It can be developed suddenly during any other tests.

A problem can be suspected by a doctor if there is:

• High blood pressure that begins suddenly and worsens
• High blood pressure before age 30 or after age 50
• Elevated protein levels in the urine
• Fluid overload and swelling in the body’s tissue

Diagnosis of renal artery stenosis:

Certain diagnose techniques may include:

• Blood test and urine test to measure the elevate kidney function
• Kidney ultrasound, which shows the size and structure of the kidney
• Doppler ultrasound, which measures blood flow speeds in the arteries of the kidney
• Magentic resonance anteriogram and computed tomographic angiography, imaging study that uses a special dye to produce 3-D images of kidney and blood vessels.

Treatments of renal artery stenosis:

There may certain treatment procedures, which include:

• Lifestyle changes- Changing certain lifestyle to decrease blood pressure, such as to be physically active, reduce stress levels, eating aa healthy diet etc.
• Medication- Certain medications can be used to treat high blood pressure associated with renal artery stenosis, such as:
  
• Angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs)- It helps to relax the blood vessels and block the formation of angiotensin II which narrows the blood vessels.
• Diuretics- It help body eliminate excess sodium and water
• Beta blockers- It widens the blood vessels and help the heart beat slower
  
• Surgery- In some severe cases surgery may be the option to remove stenosis, which are:
  
• Renal angioplasty and stenting-The narrowed vessels if opened up and a device is placed that helps the vessel to remain open and allows better blood flow.
• Renal artery bypass surgery- Making a new route for the blood to reach the kidney by grafting a substitute blood vessel to the renal artery.