Mary, a female in her early twenties, developed fatigue, low grade fever, knee pain, loss of weight, and abdominal pain.  She also presented with high blood pressure.  During physical examination, her left arm pulse was very weak.  An angiogram revealed narrowing, stenosis and occlusion, at the major branch of the aorta, renal and superior mesenteric arteries.  She was first treated with a high dose of prednisone and Methotrexate, and her treatment plan is to have revascularization when inflammation has subsided.

Takayasu’s Vasculitis, or Takayasu’s Arteritis (TAK), is a rare form of autoimmune vasculitis involving inflammation of the walls of the large arteries in the body–the aorta and its main branches.  Subsequent vascular inflammation leads to narrowing of the arteries, and eventually, reduced blood flow to affected organs.   TAK can result in a weak pulse or even loss of pulse in arms and legs.  For this reason, it is also known as the “pulseless disease”.

TAK was first described in 1908 by Dr. Mikito Takaysus.  TAK is a very rare disease and its estimated annual incidence in North America is only 2.6 cases per one million people.  Women are affected up to 10 times more than men, and peak incidence occurs in the 3rd decade of life.  TAK is most common is Asia.  Sometimes the condition runs in families.  Exactly what causes the initial inflammation in TAK is unknown; however, the disease may be triggered by a virus or infection.  It is likely the condition is an autoimmune disease, one in which the immune system attacks the body’s own arteries by mistake.

With TAK, the aorta and other major arteries, including arteries leading to the heart, brain and kidneys, become inflamed, resulting in thickening, narrowing, scarring and occlusion.  Patients can develop high blood pressure, heart failure or stroke.  Inflamed arteries can be abnormally dilated (resulting in aneurysm) and even rupture.

Visceral artery involvement is reported in 20-40% of cases.  Due to the body developing collateral vessels, symptoms usually do not occur unless two of the three main mesenteric vessels of abdomen are compromised.  Patients can experience abdominal pain after eating, abdomen distension, or even bowel rupture.  Patients with active disease who undergo revascularization are more likely to require later revision or risk aggravating the disease activity.  When possible, revascularization should be performed when the disease is quiescent.

Prednisone is the gold standard for initial therapy, but additional agents are needed in some cases, such as Methotrexate to decrease long term side effects of high dose prednisone.  Tocilizumab, an anti-IL-6 receptor (IL-6R) monoclonal antibody, was reported for the successful treatment of a patient with severe TAK. Even though severe TAK can be a medically debilitating illness, early diagnosis and treatment can prevent severe complications, improving the overall outcome.