What Is Giant Cell Arteritis?

Giant cell arteritis (GCA), also known as Temporal arteritis, is when the large arteries of the head, neck and arms become inflamed, particularly those at the side of the head (the temples). It is a serious condition, and it requires urgent treatment. GCA can lead to severe complications if not treated promptly.

Overview

Giant cell arteritis (GCA), also known as temporal arthritis, is a type of large vessel vasculitis. Vasculitis is a condition that causes inflammation of the blood vessel walls. It involves large and medium-sized arteritis of the scalp, neck, and arms. It frequently affects individuals older than 50 years. Giant cell arteritis is the most prevalent type of vasculitis, with an incidence rate of 10 per 100,000 adults over the age of 50.¹ GCA. It causes severe headaches and tenderness, particularly in the temples, but it can affect other parts as well. There are a variety of risk factors for the development of giant cell arteritis, including smoking, low body mass index, early menopause, and history of vascular disease, but the largest risk factor is age.¹ GCA cannot be cured, but remission can be achieved with steroids.

Causes

The exact cause of giant cell arthritis is unknown, but it is believed to involve a combination of genetic predisposition and immune system dysfunction. 

• Immune system: GCA is thought to be an autoimmune condition. The body's immune system, which is the body’s defence system against infections, targets healthy tissue, in this case, the walls of the blood vessels. This condition affects the temporal arteries the most (the blood vessels that carry blood to the head and brain).²
• Age- GCA is known to affect adults and is rarely seen in those under 50 years of age. Most people with this condition develop signs and symptoms between the ages of 70 and 80.³
• Genetic factors: People with a family history of GCA or other autoimmune diseases have a higher risk of developing GCA.
• Infection: Some researchers believe that infections may trigger or contribute to the development of GCA in susceptible individuals. However, the specific infectious agents, if any, are not well established.

Symptoms

The most common symptoms of GCA are: 

• Headache that is severe and persistent. The pain can be throbbing and can worsen with movement or chewing.
• Scalp tenderness, particularly over the temples.
• Vision problems such as double vision.
• Loss of vision (This may be partial, but it can sometimes be total). 
• Jaw pain while chewing or talking.
• Facial pain.
• General symptoms like fever and other flu-like symptoms.
• weight loss
• Severe fatigue often affects the quality of life.

Diagnosis

There are no established diagnostic criteria for giant cell arthritis. A diagnosis of giant cell arteritis was based largely on symptoms and a physical examination. A physical examination may reveal a temporal artery that is tender to the touch and has a reduced pulse. According to the 2023 UK guidance, it is now recommended to use temporal artery biopsy or temporal artery ultrasound as a confirmatory test for diagnosis of giant cell arthritis. Evidence reveals that diagnosis based on a patient's medical history, physical examination, and laboratory tests could result in overdiagnosis. The use of ultrasound to confirm or refute the diagnosis can enable a reduced treatment time and a reduction in the incidence of GCA complications such as vision loss.⁴

Many people believe that ultrasonography should be the first test used when there is a possibility of GCA. It is thought that GCA can be identified by the visualization of specific characteristics, such as a thicker temporal artery wall, which is called the ‘halo’ sign and a vessel whose lumen is still visible after compression, which is called the "compression sign".

The best diagnostic test to confirm the diagnosis of giant cell arteritis is conducting a biopsy of the temporal artery. The temporal artery is situated close to the skin above and in front of the ear and continues up the scalp. The procedure is performed using local anaesthesia, usually with little discomfort or scarring. Giant cell arteritis will be diagnosed if a biopsy examined under the microscope reveals abnormal cells in the arterial walls. To make the diagnosis, more than one biopsy may occasionally be needed.

Complications

If left untreated, vascular inflammation in GCA can lead to a range of disease complications. Loss of vision is the most feared short-term complication of GCA and occurs in roughly 15 to 20% of individuals. However, the progression of vision loss may be stopped by immediate therapy with glucocorticoids. Symptoms such as diplopia (double vision) and blurred vision may improve with treatment; however, complete single-eye vision loss is unlikely to recover, and, in those cases, the goal of therapy is to prevent complete bilateral vision loss [2]. Other possible complications associated with GCA include:

• Formation of aortic aneurysms
• New arterial occlusion 
• Stroke or transient ischaemic attack 
• End-stage kidney disease 
• Myocardial infarction 
• Heart failure 
• Aortic regurgitation

Treatment

Giant cell arthritis can be treated with high doses of a glucocorticoid (steroids) medication such as prednisolone. Glucocorticoids provide rapid relief of symptoms and reduce the risk of vision loss in GCA.² The immune system is suppressed by steroids, and blood vessel inflammation is decreased. The symptoms of giant cell arteritis improve within a few days of the beginning of treatment. However, high doses of steroids taken for a long time can lead to some serious side effects, such as osteoporosis, high blood pressure and muscle weakness. Hence, it is essential to monitor bone density and take calcium and vitamin D supplements to prevent bone loss.

Immune suppressive medications like Tocilizumab can also be given. Tocilizumab is a monoclonal antibody and works by blocking the inflammatory protein IL-6, which improves symptoms caused by inflammation. Methotrexate is another type of immunosuppressant. It slows down the body’s immune system and helps with the reduction of swelling.¹

FAQ

Is giant cell arteritis serious?

Giant cell arteritis is a serious condition that requires immediate treatment. It is associated with some very severe complications, such as blindness, aortic aneurysms and stroke. The symptoms can be resolved with urgent steroid treatment. Giant cell arteritis has an excellent prognosis when it is diagnosed and treated early.

What are the red flags for temporal arteritis?

It's essential to recognise the red flags for Giant cell arthritis, as accurate medical evaluation and treatment with steroids are necessary to prevent complications. The most commonly seen symptoms of Giant cell arthritis are:

• New onset headache, which is severe and persistent. It is often located in the temple region on either one or both sides. The discomfort may be throbbing and get worse when you move or chew.
• Tenderness: The temporal arteries, particularly around the temples, may be sensitive or painful to the touch.
• Sudden and transient vision loss
• Jaw pain during or after talking or eating food.

Can giant cell arteritis be cured?

There is no cure for giant cell arthritis. However, glucocorticoid therapy is highly effective and typically takes effect within a few days. The most widely used steroid is prednisolone. Glucocorticoids suppress the immune system and decrease inflammation in the blood vessel inflammation.

What lifestyle changes can help with giant cell arthritis?

The following suggestions can help manage GCA and help cope with the side effects of steroid medication:

• Eating a healthy diet can help prevent complications such as osteoporosis, high blood pressure and diabetes. It is important to consume fresh fruits and vegetables, whole grains, and lean meats and fish while limiting salt, sugar and alcohol. It is essential to get enough calcium and vitamin D through diet or supplements.
• Regular exercise, such as walking, can help promote health and prevent bone loss, high blood pressure and diabetes. 
• Regular check-ups with your doctor to check for side effects of treatment and development of complications.

When to see the doctor?

Contact your doctor immediately if you observe: 

• A sudden onset severe headache is often located on the temple region of the head. The headache is persistent and often accompanied by tenderness around the temples.
• Sudden and transient vision loss
• Jaw pain during or after talking or eating food.

If GCA is left untreated, these symptoms can progress to permanent blindness or a stroke.

What is the average age of onset for giant cell arteritis?

Giant Cell Arthritis is a condition that primarily affects elderly people, who are typically older than 50. The average age of presentation is usually between 74 and 76 years, and incidence usually increases with age. The oldest affected is around 80 years.⁵

Summary

Giant cell arteritis (GCA), also known as temporal arteritis, is a type of inflammatory disease that affects the blood vessels, particularly large and medium-sized arteries. It commonly occurs in individuals over the age of 50. GCA can cause severe headaches, tenderness in the temples, and vision problems. If left untreated, it can lead to serious complications, including blindness. Treatment usually involves corticosteroid medications to reduce inflammation and prevent complications such as permanent vision loss and stroke. Regular monitoring and medical care are essential to manage the condition effectively.