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Takayasu Disease
In 1908, there was an ophthalmologist named Dr.
Mikoto Takayasu who reported ocular changes in
a 21 year old Japanese woman. Subsequently,
Dr. Onishi and Dr. Kagoshima mentioned similar
manifestations with the addition of absent pulses
in the arms. Data collected through the years
framed the criteria for classifications and
presentation of Takayasu's Arteritis. By 1975, the
disease was formally labeled Takayasu's Arteritis.
Takayasu's Arteritis is a rare, chronic,
inflammatory disease primarily of the aorta and its
branches. TA is occasionally called "pulseless
disease" because there is difficulty in detecting
peripheral pulses that sometimes occurs as a
result of the vascular narrowing. It is also
common for a patient to exhibit vascular bruits,
and symptoms of their arterial involvement.
Takayasu arteritis is a granulomatous vasculitis of
unknown etiology that commonly affects the
thoracic and abdominal aorta. It causes intimal
fibroproliferation of the aorta, great vessels,
pulmonary arteries, and renal arteries and results
in segmental stenosis, occlusion, dilatation, and
aneurysmal formation in these vessels. Takayasu
arteritis is the only form of aortitis that causes
stenosis and occlusion of the aorta.
TA has been reported in identical twins, leading to
hypotheses of a hereditary basis for disease. In
Japan and Korea, TA is associated with human
leukocyte antigens HLA-A10, B5, Bw52, DR2,
and DR4.
These associations have not been confirmed in
Western studies.
TA is associated with HLA-B22 in the US.
Synonyms include:
- pulseless disease,
- aorta arch syndrome,
- reverse coarction,
- young female arteritis
Pathophysiology:
The mechanism of Takayasu disease has not
been fully elucidated to date. It begins as a
nonspecific, cell-mediated inflammatory process
in the patient's first 2 decades of life and
progresses to the formation of fibrotic stenoses of
the aorta and its major branches.
Frequency:
* In the US: In Minnesota's Olmstead County,
incidence of TA was estimated at 2.6 per million.
* Internationally: Most cases are reported in Asia,
although the disease occurs worldwide.
TA is a common affliction in third world countries, where
the disease is associated closely with tuberculosis.
The nature of this association is unclear because most
patients with TA in the US do not have tuberculosis.
In contrast, many third world physicians assume
tuberculosis in every patient with TA.
Mortality related to Takayasu arteritis is usually
the result of vascular complications such as
hypertension, stroke, and aortic insufficiency.
Because the disease is rare in the US, accurate
survival data are uncertain. One study has quoted
a survival rate of 85-95% at 15 years. In a 1994
study, only 2% of deaths were attributed directly
to TA. Japanese studies also support 90-95%
survival rates.
Race: Classic Takayasu arteritis is described in the
Asian population; it is also reported in all ethnic groups.
Sex: Takayasu arteritis most commonly occurs in female
patients, with a female-to-male ratio of 8:1.
Age: In approximately 90% of cases, Takayasu arteritis
appears in patients younger than 30 years.
Takayasu disease is divided into early and late
phases. The early phase is inflammatory and has
been called the prepulseless phase, and the late
phase is an occlusive one called the pulseless
phase. Patients may present with nonspecific
signs and symptoms such as fever, arthralgias,
and weight loss.
* Systemic symptoms include the following:
o Fever, night sweats
o Fatigue
o Weight loss
o Myalgia and/or arthralgia and/or arthritis
o Skin rash (eg, erythema nodosum, pyoderma
gangrenosum)
o Headaches and/or dizziness and/or syncope
o Congestive heart failure, palpitations, angina
o Hypertension (may be paroxysmal)
* Symptoms related to ischemia include the following:
o Ischemic stroke and/or transient ischemic attack
o Visual disturbances (eg, blurred vision, diplopia,
amaurosis)
o Carotidynia
o Abdominal pain
o Claudications (vary due to the development of
collateral circulations)
Physical:
* Asymmetric pulses
* Diminished or absent pulses (midaortic
lesions found in children may not affect pulses)
* Asymmetric pulses (common) and absent
pulses (rare), even in the later stages of the
disease
* Poststenotic dilatations producing what appear
to be bounding pulses (often present)
* Blood pressure difference greater than
30 mm Hg between arms
* Hypertension (may be paroxysmal): Since this
typically results from renovascular compromise,
this is a high-renin hypertension.
* Bruits, especially over subclavian arteries or
aorta
•Funduscopic examination
o Retinal hemorrhages
o Venous dilatation and beading
o Microaneurysms of peripheral retina
o Optic atrophy
o Vitreous hemorrhage
* Reported skin lesions including:
- erythema nodosum-like lesions,
- pyoderma gangrenosum,
- leukocytoclastic vasculitis,
- panniculitis.
Neurologic symptoms are present in 80% of
patients with Takayasu disease that involves the
brachiocephalic arteries.
A 5- to 20-year interval may separate the acute
inflammatory stage and symptomatic arterial
occlusive stage.
Four types of late-phase Takayasu arteritis are
described on the basis of the sites of involvement as
follows:
* Type I - Classic pulseless type that involves aortic
arch and branches: brachiocephalic trunk, carotid
arteries, and subclavian arteries
* Type II - Localised to descending thoracic aorta
(distal to the arch) and abdominal aorta and its major
branches.
* Type III - Combination of type I and II
* Type IV - Localised to pulmonary artery.
The most common type is type III, which is found
in as many as 65% of patients.
The most commonly involved vessels include the
left subclavian artery (50%), left common carotid
artery (20%), brachiocephalic trunk, renal
arteries, celiac trunk, superior mesenteric artery,
and pulmonary arteries.
Infrequently, the axillary, brachial, vertebral,
coronary, and iliac arteries are involved.
Making the diagnosis of TA can be extremely difficult.
Unfortunately, it is very common for the disease to
"smolder" in the walls of large blood vessels for many
years, causing only non- specific symptoms, until major
complication results. This can eventually lead to
occlusion, complete closing of the vessels. There can be
major complications resulting, in the dilation of the aorta
with stretching of the aortic valve in the heart, resulting
in severe valve damage, and critically reduced blood
flow to an arm or leg. In addition, a stroke caused by
high blood pressure of the blood vessels going to the
brain, renal failure, and many other serious afflictions
are also possible.
Delay in diagnosis is common even when working with
physicians experienced in vascular disease.
Lab Studies:
* TA has no specific markers.
* Complete blood count reveals a normochromic
normocytic anemia in 50% of patients with TA. Acute
phase reactants are elevated, with leukocytosis and
thrombocytosis.
* Westergren erythrocyte sedimentation rate is
elevated.
* Comprehensive metabolic profile may indicate
elevated transaminases and hypoalbuminemia
* The von Willebrand factor–related antigen (factor VIII–
related antigen) may be elevated.
* Antiendothelial antibodies are present.
* Antinuclear antibody usually is negative.
* Rheumatoid factor is elevated in 15% of individuals
with TA.
* Increased levels of immunoglobulins G, M, and A are
present.
Imaging Studies:
Arteriography is the criterion standard for assisting in
making the diagnosis of TA.
However, the use of MRA is increasing rapidly.
Arteriography often demonstrates long, smooth, tapered
narrowings or occlusions. Stenoses occur in 90-100% of
patients with TA and aneurysm formation in only 27%.
Some authors recommend arteriography of the entire
aorta.
* Magnetic resonance imaging, magnetic resonance
angiography, computed tomography
o These examinations are useful for serial
examinations and diagnosis in the early phase of TA.
o CT scan and MRI may demonstrate mural
thickening of the aorta and luminal narrowing.
o Use of contrast may reveal inflammatory lesions
prior to the development of stenoses; these lesions may
be missed by angiography.
o Aortic lesions including stenosis, dilatation, wall
thickening, and mural thrombi are well visualized on
MRI, which is less adequate in visualizing distal lesions
of the subclavian vessels and common carotids.
* High-resolution ultrasonography
o Duplex Doppler may be used to evaluate and
monitor disease in the common carotids and subclavian
arteries; however, this imaging study is not useful in
evaluating the aorta.
o Carotid evaluation reveals a homogenous
circumferential thickening of the vessel wall that is
distinguishable from atherosclerotic thickening.
* Chest radiography:
Chest radiographs may reveal:
- widening of the ascending aorta,
- irregular descending aorta,
- aortic calcifications,
- rib notching (late findings).
* Echocardiography
o Perform echocardiography at baseline to
evaluate the aortic valve.
o Perform follow-up echocardiography as
indicated to monitor aortic insufficiency.
Histologic Findings: Mononuclear infiltration of the
adventitia with perivascular cuffing of the vasa vasorum
occurs early in the disease. Granulomatous changes
may be observed in the tunica media with Langerhans
cells and central necrosis of elastic fibers and smooth
muscle cells. Later, fibrosis of the media and acellular
thickening of the intima may compromise the vessel
lumen. Grossly, wrinkling of the intima is found.
Histologic specimens seldom are available due to the
large vessels affected, with the exceptions of specimens
obtained during autopsy and bypass surgery.
Early corticosteroid therapy can improve the
clinical findings and aid in subsidence of the
active inflammatory process of Takayasu arteritis.
Prednisone is usually effective in controlling the
clinical symptoms of Takayasu arteritis and in
controlling and decreasing the progression of
active disease in patients. Other medications that
can be used as alternative or adjuvant therapy
include cyclophosphamide and methotrexate.
Each has systemic adverse effects.
The long-term prognosis is not predictable. Some
researchers have found that the prognosis is
worse when the retina of the eyes are affected or
if the aorta is damaged or when aneurysms
develop.
The effects of Takayasu arteritis vary greatly from
patient to patient. These effects frequently
depend on the impaired blood supply to body
tissues (such as the brain leading to strokes or
spinal cord leading to paralysis).
Angioplasty is an accepted and successful treatment of
patients with Takayasu arteritis, especially after the
acute inflammatory phase has abated.
The best results have been obtained with short-segment
stenoses, particularly in the iliac and renal arteries.
Angioplasty is generally contraindicated during the acute
phase of the disease.
Stent use is reported in small numbers of cases as well.
Complications:
* Congestive heart failure due to aortic
insufficiency, myocarditis, and/or hypertension
* Aortic aneurysms, thrombus formation, and
rupture
* Ischemic stroke
* Clinically silent progressive disease and
morbidity resulting from treatment medications
(take into account with long-term treatment plans)
Prognosis:
* TA is a chronic relapsing disease. Over half of
patients with TA achieve control on corticosteroids alone;
however, their relapse rate is high and they require long
periods of steroid treatment.
verll prgnosis in individuals with TA relates to the
degree of vascular and end-organ damage, specifically
retinal vasculopathy, aortic insufficiency, aortic
aneurysms, and hypertension.
* Survival rate at 15 years is as high as 95%.
* Of patients with TA who are treated with
glucocorticoids, 60% respond; however, as many as
40% relapse on tapering steroids.
Picture 1. Complete occlusion of the left common carotid artery in
a 48-year-old woman with Takayasu disease. Also note narrowing
of the origin of the right subclavian artery and a narrowed small
vessel with subsequent aneurysmal dilatation on the right side.
Caption: Picture 2. Characteristic long, tapered,
narrowing of the distal aorta and iliac vessels.
Picture 3. Image obtained in the same patient as in
Image 2 reveals narrowing of the proximal descending
aorta and right brachiocephalic artery
.