🔅Giant cell arteritis (GCA), also commonly referred to as temporal arteritis, is a condition that causes inflammation of the large and medium-sized arteries in the head and neck.
– It can affect the blood supply to the eyes, scalp, face, and other organs, leading to serious complications such as vision loss, stroke, and aortic aneurysm. GCA is more common in older adults, especially women, and people of European descent.
– The exact cause of GCA is unknown, but it is thought to involve an abnormal immune response that attacks the walls of the arteries.
RISK FACTORS THAT TRIGGER GCA
– Some factors that may increase the risk of developing GCA include:
1). Age
GCA rarely occurs in people younger than 50 years old and peaks in incidence between 70 and 80 years old.
2). Gender
Women are two to three times more likely to develop GCA than men.
3). Family history
Having a close relative with GCA may increase the chance of developing the condition.
4). Polymyalgia rheumatica
This is an inflammatory disorder that causes pain and stiffness in the muscles around the shoulders, neck, and hips. About half of the people with GCA also have polymyalgia rheumatica.
SIGNS AND SYMPTOMS OF GCA
– The signs and symptoms of GCA depend on which arteries are affected and how severe the inflammation is.
– The most common symptoms are:
• Headache: This is usually severe and persistent, affecting one or both sides of the head, especially the temples.
• Scalp tenderness: The scalp may feel sore or tender to touch, especially over the inflamed arteries.
• Jaw pain: This occurs when chewing or opening the mouth wide and usually improves with rest.
• Vision problems: These may include blurred vision, double vision, or sudden loss of vision in one or both eyes. Vision loss can be permanent if not treated promptly.
• Fever and fatigue: These are general symptoms of inflammation and infection that may accompany GCA.
• Weight loss and loss of appetite: These are also nonspecific symptoms that may occur with GCA.
DIAGNOSIS OF GCA
– The diagnosis of GCA is based on the clinical features, blood tests, imaging tests, and biopsy.
– The following tests may be used to help diagnose GCA and monitor its treatment:
🔅 Blood tests
– These measure the level of inflammation in the body by checking the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). These tests are usually elevated in people with GCA. Other blood tests may check the hemoglobin level and hematocrit to detect anemia, which can occur with chronic inflammation.
🔅 Imaging tests
– These use sound waves, magnetic fields, or radioactive tracers to produce images of the blood vessels and highlight areas of inflammation. The imaging tests that may be used for GCA include Doppler ultrasound, magnetic resonance angiography (MRA), positron emission tomography (PET), or computed tomography (CT) scan.
🔅 Biopsy
– This is the most definitive test for confirming the diagnosis of GCA. It involves taking a small sample of the temporal artery (the artery that runs along the side of the head) under local anesthesia and examining it under a microscope for signs of inflammation. The biopsy may show abnormally large cells called giant cells, which give the condition its name.
TREATMENT OF GCA
– The treatment of GCA aims to reduce inflammation, relieve symptoms, prevent complications, and minimize side effects.
– The main treatment for GCA is high-dose corticosteroids, such as prednisone, which are effective in reducing inflammation and preventing vision loss.
– The treatment usually starts as soon as possible after the diagnosis is suspected, even before confirming it with a biopsy.
The initial dose of corticosteroids is usually 40 to 60 mg per day (or equivalent), given in a single daily dose. The dose may be increased or decreased depending on the response and side effects.
– The treatment duration varies from person to person, but typically lasts for one to two years. The dose is gradually tapered over time to avoid withdrawal symptoms and reduce the risk of relapse.
– Corticosteroids can cause many side effects, such as weight gain, high blood pressure, high blood sugar, osteoporosis, infections, mood changes, cataracts, glaucoma, and skin thinning. Therefore, people taking corticosteroids need regular monitoring by their doctor and may need to take other medications to prevent or treat these side effects.
MEDICATIONS
– Some examples of these medications are:
• Low-dose aspirin: This helps prevent blood clots that can cause stroke or heart attack in people with GCA.
• Proton pump inhibitors (PPIs): These reduce stomach acid production and lower the risk of developing stomach ulcers or bleeding from corticosteroids.
• Bisphosphonates: These strengthen the bones and prevent osteoporosis from corticosteroids.
• Immunomodulators: These are drugs that modify the immune system and reduce inflammation. They may be used as steroid-sparing agents in some people with GCA who cannot tolerate high doses or long-term use of corticosteroids. Examples of these drugs are: methotrexate, azathioprine, and tocilizumab.
PREVENTION OF GCA
– There is no known way to prevent GCA, but early diagnosis and treatment can prevent or minimize its complications.
– People who have risk factors for GCA, such as older age, female gender, European ancestry, or polymyalgia rheumatica, should be aware of the signs and symptoms of GCA and seek medical attention promptly if they develop them.
– People who are diagnosed with GCA should follow their doctor's instructions regarding medication use, monitoring, and follow-up visits. They should also adopt a healthy lifestyle that includes:
• Eating a balanced diet that is rich in calcium and vitamin D to protect the bones from osteoporosis.
• Involvement in regular physical exercise/ activity that is appropriate for their age and condition to maintain muscle strength and cardiovascular health.
• Quitting smoking if they smoke, as smoking can worsen inflammation and increase the risk of cardiovascular disease.
• Managing stress and getting enough sleep to improve their mood and well-being.
GCA is a serious condition that requires prompt diagnosis and treatment to prevent vision loss and other complications. With proper care and management, most people with GCA can achieve remission and have a good quality of life.
