Giant Cell Arteritis (Temporal Arteritis)
Giant Cell (temporal) Arteritis (GCA) is a vasculitis of large and medium size vessels. It may be generalized but vessel inflammation most frequently involves vessels in the scalp and head, especially the arteries over the temples. The disease is called temporal arteritis because the temporal arteries, which course along the sides of the head just in front of the ears (to the temples) often become inflamed. Women, Caucasians, and individuals over 50 years of age are most commonly affected by GCA.
The onset of the symptoms in GCA tends to be gradual and includes low grade fever, fatigue, weakness and weight loss. A new headache, mild or severe, occurs in at least two-thirds of patients with the pain tending to be located over the sides of the head in front of the ears but may be frontal or other located. Nearly one-half of patients suffer from pain in the jaw after chewing (called jaw claudication). Impaired vision is often an early manifestation of the disease.
Permanent partial or complete loss of vision in one or both eyes has been observed in 15-20 % of patients. It is rare for patients to become completely blind in both eyes.
Polymyalgia rheumatica (PMR), which is characterized by pain in the shoulders and hips, is closely linked to GCA, occurring in about 40-50 % of patients.
A laboratory abnormality seen in most patients with GCA is a very high erythrocyte sedimentation rate (ESR). The ESR measures how fast a patient’s red blood cells settle when placed in a small tube. Anemia or low red blood cell count and microscopic hematuria (blood in the urine) may be found but renal (kidney) impairment is unlikely to be due to GCA. Other tests are occasionally abnormal with non specific meaning.
Temporal artery biopsy is suggested in all cases of suspected GCA. Even though the diagnosis may appear "classic" a temporal artery biopsy is still recommended. The biopsy is of low risk, causes very little pain, and often leaves little or no scar. After the use of a topical numbing medication (the same one used by a dentist), the doctor can remove a small part of the temporal artery from under the scalp in order to examine it under the microscope.
Other ways to diagnose GCA include: ultrasonography, angiographic examination, computerized topographic scanning and magnetic resonance angiography, high resolution magnetic resonance imaging and position emission tomography (PET).
Glucocorticoid treatment should be instituted once the diagnosis of GCA is established. Glucocorticoids have inhibitory effects on a broad range of specific immune responses. Their effectiveness in GCA is well established by years of use. Daily dosing is more effective than alternate day dosing. This response usually occurs within two to four weeks after the institution of therapy. The diagnosis should be reevaluated in patients who are resistant to adequate steroid therapy. Steroid withdrawal can begin once clinical remission has been induced. Relapses are seen more frequently in the first year or two of the disease.
Adverse effects of corticosteroids are glucose intolerance or frank diabetes mellitus (condition of abnormal glucose levels in blood) and infections. Patients should be aware and watchful so as to report symptoms suggestive of diabetes or infection. Use of glucocorticoids may also predispose to, or worsen preexisting, osteoporosis (abnormal bone density condition) especially in postmenopausal women and older men. Use of calcium supplements, vitamin D, hormone replacement therapy and/or bisphosphonates are can be helpful in preventing bone mineral loss.
Relapses often necessitate increased dosage or prolonged steroid treatment. Some researchers have suggested that the addition of methotrexate may be steroid-sparing while others have not demonstrated any benefit. However the routine addition of methotrexate to glucocorticoid therapy for GCA is not recommended. The efficacy of other cytotoxic drugs, dapsone, antimalarials, etanercept, and penicillamine has not been studied adequately although they have been reported to be helpful in some case reports.
The finding of an increased risk of visual loss in patients with GCA and thrombocytosis (increase of the number of platelets in the blood), has led some to suggest the addition of drugs like aspirin for patients with high platelet counts, but there is not a lot of data to prove that this may reduce brain/skull problems.
Read stories about people with Giant cell arteritis.
Early Treatment Affects Vasculitis - Concentrating on GCA
By Jeff Hersh, Ph.D., M.D., F.A.A.P., F.A.C.P., F.A.A.E.P.
Karla Charest, R.N., contributed to this column
This week (Sept. 23 to 29) is vasculitis awareness week, so today's column is dedicated to increasing awareness of these diseases.
Vasculitis is inflammation of a blood vessel(s). The symptoms and complications that occur from vasculitis depend on which vessels are affected and the extent of the inflammation. This inflammation can cause systemic (total body) symptoms such as fever, fatigue or weight loss, as well as localized symptoms from inhibited blood flow through the affected vessels, or complications from weakening or other changes of the vessels themselves.
Since there are so many different types of blood vessels (veins and arteries of various sizes, essentially everywhere in the body) it is not surprising that there are many different types of vasculitis causing a variety of different diseases.
Rather than try to discuss many different conditions in a vague way, we thought it better to discuss one type of vasculitis in a more comprehensive way. Today's discussion will focus on giant cell arteritis (GCA), also known as temporal arteritis.
Vessel inflammation in GCA most frequently involves the arteries in the scalp and head, especially the arteries over the temples (hence the name temporal arteritis), so many of the symptoms from GCA come from inhibition of blood flow through these vessels, as well as from the generalized inflammatory process.
Some of the initial symptoms of GCA are caused by the generalized inflammatory process and are as already described. The specific artery involvement in GCA will often lead to new-onset headaches, usually in the temporal area, which occur in at least two-thirds of GCA patients. Nearly one-half of GCA patients suffer from pain in the jaw after chewing (called jaw claudication).
Impaired vision is another common early symptom of GCA; in fact over 50 percent of GCA patents seek medical care because of the visual symptoms. These symptoms may include amaurosis fugax (transient loss of vision in one eye) or gradual, progressive vision loss in one or both eyes. Permanent vision loss in one or both eyes occurs in up to 15 percent to 20 percent of GCA patients, usually in people who have delayed seeking medical care for their progressive visual loss symptoms. New visual loss, once treatment has begun, is rare and occurs in only about 1 percent of patients. Thankfully, it is rare for GCA patients to become completely blind in both eyes.
Many other symptoms and complications can occur in GCA patients. About 3 percent to 15 percent will have the disease affect branches of the aortic artery arch, narrowing these vessels and leading to arm claudication (cramp-like pain). Aortic aneurysms (bulging due to weakening of the artery's wall) can also occur and can be fatal if they rupture. Overall, GCA is fairly uncommon, with an incidence of 100 to 500 per million people. However, GCA becomes much more common as people get older, with an average age of onset of 72 years old. In fact, up to 1 in 100 people over age 80 develop GCA. Female sex, Caucasian race, family history of GCA and Northern European or Scandinavian heritage are other known risk factors for developing GCA.
GCA is suspected based on the history and physical exam, especially in an elderly patient or someone else who is felt to be at higher risk for this disease. Because untreated GCA can lead to permanent vision loss, it is very important to consider GCA in the differential diagnosis of appropriate patients.
There is a blood test that can be done rapidly to help evaluate patients suspected of having GCA, and this is called the erythrocyte sedimentation rate (ESR). This is a very sensitive test for GCA; the result of this test will be abnormal in over 85 percent to 90 percent of patients who have the disease. Therefore, an ESR will usually be done to evaluate patients suspected of having GCA. However, the test is very non-specific; an abnormal test can occur for many reasons, and so an abnormal result does NOT imply the patient has the disease. If the result is abnormal, then treatment will be started (see below) and the more definitive test, a temporal artery biopsy, will be done.
Temporal artery biopsy is low risk, causes very little pain, and usually leaves only a minimal scar. Although temporal artery biopsy is the best test for GCA, it is not perfect and there is a possibility of false negative results, so sometimes a second temporal artery biopsy (or a biopsy of a different artery) is performed.
In order to distinguish GCA from other types of vasculitis, the American College of Rheumatology notes the following criteria for vasculitis patients to make the diagnosis of GCA:
- Age over 50
- Localized headache of new onset
- Tenderness or decreased pulse of temporal artery
- ESR over 50
- Biopsy revealing a necrotizing arteritis with typical cells (mononuclear or multinucleated cells)
Having at least three of these five criteria is over 90 percent sensitive and 90 percent specific to make the diagnosis of GCA in vasculitis patients.
Glucocorticoid (a type of steroid, for example, prednisone) treatment should be started as soon as the diagnosis of GCA is strongly suspected. Glucocorticoids have inhibitory effects on a broad range of immune/inflammatory conditions and are very effective as treatment for GCA; with response to therapy usually occurring very soon after it is started. Gradually tapering (lowering the dosages) these medications will begin once clinical remission has been induced, usually two to four weeks after starting therapy.
In most patients, treated GCA resolves over months to several years, and this is when steroid treatment can be completely stopped. There are many possible side effects and complications from steroid therapy, especially long-term therapy, so patients being treated need to be made aware of these and need to be closely monitored by their health care provider. Other immune suppressing medications can be considered in selected patients who cannot tolerate steroids or whose disease does not respond well to them.
Relapses of GCA (signaled by return of symptoms) are seen more frequently in the first year or two of the disease and may occur if steroids are withdrawn or tapered too quickly. Relapses may require increased steroid dosages or longer treatments.
One of the many reasons to promote increased awareness of vasculitis is to encourage people to seek medical care early so the complications of these diseases can be minimized and quality of life improved. For GCA, early diagnosis and treatment can prevent permanent vision loss, so it is crucial that people with symptoms of GCA seek medical care immediately.
Giant Cell Arteritis Patient Resources
Pearl Rupp became ill with Giant Cell Arteritis (GCA) and Polymyalgia Rheumatica (PMR) in 1998 at age 65. It was diagnosed after she lost vision permanently in one eye. During her illness, her husband, James, compiled a detailed list of medical journal articles on GCA research. Click here to read.