What is giant cell arteritis?
Giant cell arteritis (GCA) is a condition in which medium and large arteries, usually in the head and neck, become inflamed.
As the arteries around the temples are usually affected, giant cell arteritis is sometimes called temporal arteritis.
The condition is one of the most common types of vasculitis, which is the general term for the inflammation of arteries and veins (blood vessels).
Symptoms of giant cell arteritis include:
- aching and soreness in and around the temples
- jaw muscle pain while eating
- vision loss
These can often develop suddenly, but may follow vague symptoms such as weight loss and prolonged tiredness.
Read more about the symptoms of giant cell arteritis.
Seeking medical help
Giant cell arteritis should be regarded as a medical emergency because without prompt treatment it can lead to permanent visual impairment.
You should contact your doctor immediately if you suddenly develop a severe headache, jaw pain when eating, blurred or double vision, or a sore scalp.
Diagnosis and treatment
Treatment for giant cell arteritis will usually begin as soon as possible. This may mean that treatment begins before a diagnosis is confirmed.
An examination of your symptoms and blood tests may be carried out if it is thought that you have giant cell arteritis. However, the most effective way to diagnose the condition is to remove some tissue from your temporal artery, so that it can be studied. This procedure is known as a temporal artery biopsy.
The main treatment for giant cell arteritis is steroid medication (corticosteroids. Most people need to take steroids on a long-term basis to help prevent their symptoms returning. A two-year course of corticosteroids is usually required.
Other types of medication, such as low-dose aspirin and immunosuppressants (medication that suppresses the immune system), may also be used along with corticosteroids to reduce the risk of the condition recurring and complications developing.
Although treatment can reduce the risk of serious complications, the damage to the blood vessels associated with giant cell arteritis can increase the risk of other serious problems developing. These include permanent visual impairment, abdominal aortic aneurysm and cardiovascular disease.
Read more about the possible complications of giant cell arteritis.
Who is affected?
Giant cell arteritis is a fairly uncommon condition.
The condition is age-related. It only tends to affect adults over the age of 50, and it is usually adults over 60 years old who develop it.
The condition is three times more common in women than in men. It is also seven times more common in white people than in black people.
The cause of giant cell arteritis is unclear. However, it is thought that a combination of genetic and environmental factors - such as an infection - may be responsible for the condition.
Giant cell arteritis symptoms
The most common symptom of giant cell arteritis (GCA) is a mild to severe headache, although some people also experience jaw pain and vision problems.
The symptoms of usually develop quite quickly, although many people report experiencing more general symptoms, such as weight loss or feeling tired all the time, for several weeks or months before more symptoms appear.
About two thirds of people with giant cell arteritis experience a headache that develops suddenly. It most often affects the front or side of the head (temples), but can affect the back or the top of the head, or behind the ears. These areas may also feel tender.
Many people with giant cell arteritis have described the headache as unlike any type of headache they have experienced before. Painkillers, such as paracetamol, are not usually effective at treating the pain.
Your scalp may also feel sore and tender when brushing your hair. In many cases, the arteries in the temples (temporal arteries) are visibly swollen.
Jaw pain and vision problems
Although less common, people with giant cell arteritis may also experience jaw pain (jaw claudication) and visual disturbances.
Jaw pain related to giant cell arteritis typically occurs when chewing or talking. The pain usually stops when the jaw is rested. In some cases, this pain is felt in the tongue. About one in five people with the condition report this type of jaw pain.
Vision problems also affect about one in five people with giant cell arteritis. This usually takes the form of partial or, less often, complete vision loss in one or both eyes. This type of vision disturbance has been described as like having a shade covering your eye. If the condition is left untreated, this can progress to total blindness.
Many people will experience episodes of double vision before the loss of vision occurs.
Other common symptoms of giant cell arteritis include:
- mild fever, with a temperature of 37°C-38°C (98.6°F-100.4°F)
- fatigue (extreme tiredness)
- loss of appetite
- weight loss
When to seek medical advice
It is very important that giant cell arteritis is treated as soon as possible to reduce the risk of blindness. However, this can be difficult because the initial symptoms of giant cell arteritis can often be vague.
Researchers have identified a number of important warning signs that could indicate that your vision may be at risk. These include:
- suddenly developing a severe headache
- pain in your jaw muscles when eating
- double vision
- your scalp is sore or tender to the touch
Contact your doctor immediately if you develop any of these symptoms.
Diagnosing giant cell arteritis
If your doctor thinks you may have giant cell arteritis (GCA) they will ask you about your symptoms and carry out an examination of your head.
This is because giant cell arteritis can cause physical signs, such as noticeably swollen arteries in your temples (temporal arteries).
If your doctor suspects you may have giant cell arteritis, they may refer you for blood tests, which can be used to assess the levels of inflammation inside your body.
If you have any disturbances to your vision, it is likely that your doctor will arrange a same-day appointment with an eye specialist (ophthalmologist). This will usually be at your local hospital or eye clinic.
To assist with the diagnosis, the ophthalmologist will use special equipment, such as a microscope that is specifically designed to examine the eyes. This can help to check for changes in your eyes that are known to be associated with giant cell arteritis, such as bleeding or swelling at the site of your optic nerve.
A temporal artery biopsy is the most effective method of diagnosing giant cell arteritis.
During the procedure, the skin on the side of your head is numbed with a local anaesthetic. An incision is made in your skin, close to the hairline in front of your ear, and a small sample of your temporal artery is removed. The incision will then be sealed with stitches.
Once a sample of your temporal artery has been removed it can be studied under a microscope in a laboratory to check for evidence of damage and inflammation to the lining of the arteries. It can take several days to obtain the results of a biopsy.
Therefore, if a diagnosis of giant cell arteritis is suspected, it is likely that treatment with steroid medication (corticosteroids will begin immediately. Waiting until the results of the biopsy are known could be dangerous in terms of the threat to your sight.
If the results of the biopsy are negative (there is no evidence of damage or inflammation) you should not be concerned about taking corticosteroids because their short-term use poses no significant risk to your health. However, a negative biopsy does not exclude giant cell arteritis, and if your rheumatologist or ophthalmologist strongly suspects the diagnosis, you may still be prescribed steroids.
Read more about treating giant cell arteritis.
Giant cell arteritis treatment
Steroid medication (corticosteroids is the preferred treatment for giant cell arteritis (GCA). A type of steroid medicine called prednisolone is usually prescribed.
If you have symptoms indicating that your vision is at risk, you may be given an initial prednisolone injection. After this, prednisolone tablets will be prescribed for you.
If your vision is not at risk, you will be prescribed prednisolone tablets or capsules straight away. You will probably start on a relatively high dose (usually between 40 to 60 milligrams). This dose will then be gradually reduced every two to four weeks, depending on how well you respond to treatment.
You may need to take prednisolone for up to two years to prevent your symptoms returning. Your symptoms should improve significantly within a few days of starting your treatment. However, there is a chance that it will return (relapse) once treatment stops.
Do not suddenly stop taking steroid medication, unless told by a doctor that it's safe to do so. Suddenly stopping treatment with steroids can make you feel very ill.
About one in 20 people who take prednisolone will experience changes in their mental state when they take the medication.
For example, you may feel very depressed and suicidal, very anxious or very confused. Some people also experience hallucinations (feeling, seeing or hearing things that are not there). Contact your doctor as soon as possible if you experience changes to your mental state.
Other side effects of prednisolone include:
- increased appetite that often leads to weight gain
- increased blood pressure
- mood changes, such as becoming aggressive or irritable with people
- weakening of the bones (osteoporosis)
- stomach ulcers
- increased risk of infection - particularly to the virus that causes chickenpox and shingles (varicella-zoster virus).
Seek immediate medical advice if you think that you have been exposed to the varicella-zoster virus or if a member of your household develops chickenpox or shingles.
The risk of these side effects should improve as your dosage of prednisolone is decreased.
See side effects of corticosteroids for more information about how these side effects may affect you and how they are treated.
Low-dose aspirin is increasingly being recommended for people who have a history of giant cell arteritis, because it has been found to be effective in preventing complications of giant cell arteritis, such as heart attacks or stroke.
Some people with giant cell arteritis may benefit from treatment with immunosuppressants, such as methotrexate or leflunomide, that are taken along with prednisolone.
Immunosuppressants are a type of medication used to reduce or suppress the immune system (the body's defence against illness and infection). Using immunosuppressants can allow steroid medication to be reduced and can help prevent the condition recurring.
Common side effects of immunosuppressant medication include nausea, vomiting, diarrhoea and skin rashes.
The doctor in charge of your care will ask you to attend regular follow-up appointments so they can check how well you are responding to treatment. They will assess whether your dosage of prednisolone needs to be adjusted and how well you are coping with the side effects of the medication.
During these appointments you will have blood tests to check the levels of inflammation inside your body. You may also be referred for scans to assess how strong your bones are.
Follow-up appointments are usually recommended on a weekly or fortnightly basis for the first two or three months of your treatment, and then every three months after that time.
If you experience a return of your symptoms during any part of your treatment, contact your doctor because your dosage may need to be adjusted.
Complications of giant cell arteritis
People with giant cell arteritis (GCA) can sometimes develop further problems associated with the condition.
Despite the best efforts of healthcare professionals, around one in five people with giant cell arteritis will experience some degree of visual impairment. This can range from some loss of vision in one eye to total blindness.
Coming to terms with any degree of visual impairment can be an overwhelming experience, and it is likely that you will require a great deal of help and support.
Abdominal aorta aneurysm
The inflammation that is associated with giant cell arteritis can sometimes lead to a weakening in the walls of one of the major blood vessels in the body, known as the abdominal aorta. This is the main blood vessel that is responsible for taking blood from the heart and distributing it to the rest of the body.
Weakening in the walls of the abdominal aorta can lead to the formation of a bulge in the wall of the abdominal aorta, known as an aneurysm. An abdominal aorta aneurysm is potentially very serious because there is a risk that the blood vessel could burst open (rupture), resulting in massive internal bleeding and, in most cases, death.
Due to this risk, it may be recommended that you have a check-up every two years if you have a history of giant cell arteritis. During these check-ups, a number of tests, such as ultrasound scans and X-rays, can be used to check if you have developed an abdominal aorta aneurysm.
If a significant aneurysm is detected, a type of surgery known as grafting is usually recommended. This involves removing the section of the aorta that contains the aneurysm and replacing it with a piece of synthetic tubing called a graft.
Read more about treating an abdominal aortic aneurysm.
People with giant cell arteritis are also at an increased risk of developing cardiovascular disease. This is the general term for disease of the heart or blood vessels. Cardiovascular disease is a leading cause of stroke and heart attacks.
Read more about cardiovascular disease.