Giant cell (temporal) arteritis is chronic inflammation of large arteries of the head, neck, and upper body. Typically affected are the temporal arteries, which run through the temples and provide blood to part of the scalp, the jaw muscles, and salivary glands.
• The cause is unknown.
• Typically, people have a severe and often throbbing headache, pain in the scalp when they brush their hair, and pain when they chew.
• Without treatment, blindness can result.
• Symptoms and results of a physical examination suggest the diagnosis, but biopsy of the temporal artery is done to confirm it.
• Prednisone, a corticosteroid, is effective.
Giant cell arteritis typically affects people over 55. About 40 to 60% of people with giant cell arteritis also have polymyalgia rheumatica. The cause of these disorders is unknown.
Symptoms
Symptoms vary, depending on which arteries are affected. Typically, the large arteries to the head are affected, causing a severe, sometimes throbbing headache at the temples or back of the head to develop for the first time. Arteries in the temple may be tender to the touch and feel swollen and bumpy. The scalp may feel painful when the hair is brushed. Double or blurred vision, large blind spots, blindness in one eye, or other eye problems may develop. The greatest danger is permanent blindness, which can occur suddenly if the blood supply to the optic nerve is blocked. Without treatment, giant cell arteritis causes blindness in 20% of people,
Typically, the jaw and its muscles hurt and become tired soon after beginning chewing. The tongue may also hurt when eating or speaking. People may also feel tired and generally unwell. They may lose weight unintentionally and sweat more than usual.
Did You Know...
• Combing the hair and chewing often hurt when people have giant cell arteritis.
Occasionally, blood flow to the brain is blocked, and a stroke occurs. Sometimes inflammation damages the aorta, causing its lining to tear (dissection) or a bulge (aneurysm) to form in its wall.
If polymyalgia rheumatica is also present, severe pain may occur in the neck, shoulders, and hip. These muscles may feel stiff, particularly in the early morning.
Diagnosis
Doctors suspect the diagnosis based on symptoms and results of a physical examination. Doctors feel the temples to see whether the temporal arteries feel hard, bumpy, or tender. Blood tests are done. Results can support the diagnosis. For example, anemia, a very high erythrocyte sedimentation rate (ESR), and a high level of C-reactive protein indicate inflammation. A biopsy of the temporal artery (in the temple) is done to confirm the diagnosis.
If giant cell arteritis is suspected in arteries other than the temporal artery, magnetic resonance angiography may be done to confirm the diagnosis.
Treatment
Treatment is started as soon as giant cell arteritis is suspected because without treatment, blindness can develop. Treatment is usually started even before a biopsy is done. Treatment does not affect the biopsy results as long as the biopsy is done within weeks after starting treatment. Prednisone, a corticosteroid, is effective. Initially, the dose is high—to stop the inflammation in the blood vessels. After several weeks, doctors gradually reduce the dose if people are improving. Some people can stop taking prednisone within a year, but many need to take very low doses for many years to control symptoms and prevent blindness.
People should take a low dose of aspirin every day to help prevent strokes.
With treatment, most people recover fully, but the disorder may recur.
Spotlight on Aging
Giant cell (temporal) arteritis and polymyalgia rheumatica, which often occur together, affect people over age 55 almost exclusively. These disorders become more common as people age. They are 10 times more common among people over 80 than among those aged 50 to 59.
Giant cell arteritis typically causes a throbbing headache and problems with vision (including pain in and around the eyes). Polymyalgia rheumatica makes muscles painful and stiff. Without treatment, the pain these disorders cause, whether they occur together or separately, can make everyday living miserably difficult. Also, without prompt treatment, giant cell arteritis can cause blindness.
The main treatment of these disorders, corticosteroids, may be problematic in older people. These drugs can cause dramatic improvement and are essential for preventing blindness. However, they are more likely to have side effects in older people. People may retain fluids, their appetite may increase, and they may become confused. Blood sugar may increase, sometimes causing diabetes, and bone density may decrease. Blood pressure may increase. To reduce the risk of these effects, doctors reduce the dose of the corticosteroid and stop the drug as soon as possible.
Older people who take corticosteroids are encouraged to take measures to help maintain bone density. They can do weight-bearing exercise and take calcium and vitamin D supplements. Taking bisphosphonates (such as alendronate or risedronate) can help increase bone density.
Faithfully continuing treatment as instructed results in complete recovery for many people.
POLYMYALGIA RHEUMATICA
Polymyalgia rheumatica involves inflammation of the lining of joints, causing severe pain and stiffness in the muscles of the neck, shoulders, and hips.
• The cause is unknown.
• The neck, shoulders, and hips feel stiff and painful.
• Blood tests and sometimes biopsy of a muscle help doctors make the diagnosis.
• Most people improve dramatically when they take prednisone, a corticosteroid.
Polymyalgia rheumatica occurs in people over 55. Its cause is unknown. Polymyalgia rheumatica may occur with giant cell (temporal) arteritis. Some experts think that the two disorders are variations of the same abnormal process.
Symptoms
Symptoms may develop suddenly or gradually. Severe pain and stiffness occur in the neck, shoulders, and hips. The stiffness is worse in the morning and after periods of inactivity. But muscles are not damaged or weak. People may also have a fever, feel generally unwell or depressed, and lose weight unintentionally.
Some people with polymyalgia rheumatica also have symptoms of giant cell arteritis, which can lead to blindness. Some people have mild arthritis, but if the arthritis is severe or is the main symptom, the diagnosis is more likely to be rheumatoid arthritis (see Joint Disorders: Rheumatoid Arthritis (RA)).
Diagnosis
Doctor base the diagnosis on symptoms and results of a physical examination and blood tests. Blood tests usually include the following:
• Erythrocyte sedimentation rate (ESR), C-reactive protein levels, or both: In people with polymyalgia rheumatica, results of both tests are usually very high, indicating active inflammation.
• Blood count: This test is done to check for anemia.
• Thyroid-stimulating hormone: This test is done to rule out hypothyroidism, which can cause weakness and sometimes pain of the shoulder and hip muscles.
• Creatinine kinase: This test is done to check for muscle tissue damage (myopathy), which can cause weakness and pain of the shoulder and hip muscles.
• Rheumatoid factor: This antibody occurs in people with rheumatoid arthritis but not in those with polymyalgia rheumatica. This test helps doctors distinguish between the two.
If the diagnosis is unclear, a sample of muscle tissue may be removed and examined under a microscope (biopsy), or electromyography (see Diagnosis of Brain, Spinal Cord, and Nerve Disorders: Electromyography and Nerve Conduction Studies) may be done to locate the source of muscle symptoms. If the cause is polymyalgia rheumatica, these test results are normal.
Treatment
Taking a low dose of prednisone, a corticosteroid, usually causes dramatic improvement. If people also have giant cell arteritis, a higher dose is needed to reduce the risk of blindness. As the symptoms subside, the dose is gradually reduced to the lowest effective one. Many people can stop taking prednisone in 1 to 4 years, although some people need to take a low dose longer.
Aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) can help relieve pain but usually less effectively than prednisone.
Resource: Merck Manual Home Edition