Takayasu’s Arteritis is a type of vasculitis which occurs due to inflammation of the blood vessels. This type affects large blood vessels including the aorta and its major branches. It predominantly affects young women between the ages of 10 and 40 years. It is relatively rare in the United States and Europe with an incidence of 1 to 3 new cases per million annually.
The underlying cause of Takayasu’s arteritis is unclear and is suspected to be immune medicated. It shares many similarities with Giant Cell Arteritis which predominantly occurs in older individuals over the age of 60.
Symptoms of Takayasu’s Arteritis
Patients experience generalised symptoms due to ongoing inflammation such as:
The involvement of the aorta and its branches cause localised symptoms:
Pain in the arms and legs on activity due to reduced blood supply
Chest pain from involvement of the aorta and coronary vessels supplying the heart
Light-headedness and loss of consciousness from reduced blood supply to the brain, even strokes may occur
Shortness of breath and coughing up blood may occur with involvement of the vessels supplying the lung
Diagnosis of Takayasu’s Arteritis
The diagnosis is suspected based on the history and physical examination. Confirmatory tests are then ordered to establish the diagnosis
Physical Examination: The doctor would perform a complete examination including the chest, limbs, abdomen and a neurological examination. Patients may often have elevated blood pressures and/or abnormal pulses.
Inflammatory markers such as Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) may be elevated in active disease
Imaging studies: the definitive diagnosis of Takayasu Arteritis is made from looking at images of the involved blood vessels. The test commonly performed are
MRA- Magnetic Resonance angiography: this involves introducing a contrast dye into the vessels to help visualise them
CTA – Computed Tomogram angiography: This also involves inserting a dye but uses a CT machine to obtain images
Color Doppler Ultrasound: This is the use of ultrasound waves to obtain images of the vessels and can also detect the flow of blood across them
Biopsy: Obtaining a tissue from a major vessel is difficult and is hence rarely done, but can be performed for confirming the disease activity if feasible.
Complications of Takayasu’s Arteritis
Arterial Stenosis: This is a narrowing of the blood vessels resulting in poor blood supply to organs. It can affect the kidney vessels as Renal artery stenosis.
Aneurysm: This is an abnormal dilatation of the vessel. Ongoing inflammation can weaken the walls of the vessels leading a ballooning dilatation. This can affect blood supply downstream and also poses a risk of rupture.
Aortic Valve regurgitation: when disease involves the early part of the aorta it may also damage the aortic valve leading to leaking of blood around the valve causing aortic regurgitation.
Stroke: Involvement of the arteries supplying the brain can lead to damage leading to stroke
Treatment of Takayasu’s Arteritis
The goal of treating Takayasu arteritis is to control ongoing inflammation. The following medications are generally used
Steroids or glucocorticoids like prednisone: This is the treatment of choice and is generally effective at controlling the disease and results in symptomatic improvement.
Immunosuppressive medications: In case of long term requirement of steroids or absence of response to steroids, alternative medications are also effective such as methotrexate, leflunomide, azathioprine and mycophenolate mofetil.
Biologicals: these are newer drug groups which are antibodies targeted against substances in the body which lead to inflammation. Tocilizumab, infliximab and etanercept are drugs which are being investigated for use in this condition.
In case of complications of Takayasu Arteritis such as stenosis and aneurysms, surgical treatment options can be considered
Angioplasty: This is a procedure to open up narrowed vessels. It may be done through a minimally invasive route through inserting a wire through a peripheral vessel to reach the area affected.
Bypass grafts: This is a surgical procedure which is preferred when large portions of the vessel is affected and involves replacing the vessel tract with a graft.
Aortic Valve Surgery: In case of aortic regurgitation, the aortic valve may be repaired or replaced as appropriate.
Prognosis of Takayasu’s Arteritis
This is a chronic condition which undergoes waves of disease exacerbation and resolution. It can be effectively controlled with steroid use alone though the side effects can be problematic. In many individuals the disease may resolve completely leading to stopping therapy. However, it is important to monitor for return of symptoms in these cases.
References:
Arend WP, Michel BA, Bloch DA, Hunder GG, Calabrese LH, Edworthy SM, et al. The American College of Rheumatology 1990 criteria for the classification of Takayasu arteritis. Arthritis Rheum. 1990 Aug;33(8):1129–34.