Giant cell arteritis (GCA) is a condition in which medium and large arteries, usually in the head and neck, become inflamed.
It's sometimes called temporal arteritis because the arteries around the temples are usually affected.
The condition is one of the most common types of inflammation of the arteries and veins (vasculitis).
Symptoms of giant cell arteritis include:
aching and soreness in and around the temples
jaw muscle pain while eating
These can often develop suddenly, but may follow vague symptoms such as weight loss and prolonged tiredness.
When to see your GP
Giant cell arteritis needs urgent medical attention and treatment with steroids. Without prompt treatment it can lead to permanent visual impairment.
Contact your GP as soon as possible if you suddenly develop a severe headache, jaw pain when eating, blurred or double vision, or a sore scalp. If this isn't possible, contact your out-of-hours service .
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's thought you have giant cell arteritis.
The most effective way to diagnose the condition is to remove some tissue from your temporal artery so 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 prevent their symptoms returning. A two-year course of corticosteroids is usually required.
Other types of medication, such as low-dose aspirin and medication that suppresses the immune system (immunosuppressants), may also be used to reduce the risk of the condition recurring and complications developing.
The damage to the blood vessels in giant cell arteritis can increase the risk of serious problems developing. These include permanent sight loss, abdominal aortic aneurysm, and cardiovascular disease.
Who's affected by giant cell arteritis?
In the UK, it's estimated about 1 in every 4,500 people will develop giant cell arteritis each year.
It only tends to affect adults over the age of 50, and those who develop the condition are usually over 60.
Giant cell arteritis is three times more common in women than in men. It's also seven times more common in white people than in black people.
Around half of people with giant cell arteritis also develop polymyalgia rheumatic (PMR), a related but less serious condition.
Polymyalgia rheumatica causes inflammation of the muscles and sometimes the joints, resulting in symptoms that can include shoulder, neck and hip pain, and stiffness of the affected muscles (which is often most obvious after waking up).
The symptoms of polymyalgia rheumatica can develop before, after, or at the same time as the symptoms of giant cell arteritis.
Symptoms of giant cell arteritis
The most common symptom of giant cell arteritis (GCA) is a headache, although some people also experience jaw pain and vision problems.
The symptoms usually develop quite quickly, although many people report other symptoms, such as weight loss or tiredness, for weeks or months beforehand.
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 also affect the back or 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've experienced before. Painkillers, such as paracetamol, aren't 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 problems with vision.
Jaw pain typically occurs when chewing or talking. The pain usually stops when the jaw is rested. In some cases, the pain is felt in the tongue.
Vision problems affect about one in five people with giant cell arteritis. This can be in one or both eyes. It's been described as like having a shade covering your eye. Left untreated, it can lead to 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 37-38C (98.6-100.4F)
loss of appetite
When to seek medical advice
It's 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.
Warning signs that your vision may be at risk include:
suddenly developing a severe headache
pain in your jaw muscles when eating
your scalp is sore or tender to the touch
Contact your GP immediately if you develop any of these symptoms. If this isn't possible, your local out-of-hours service.
Around half of people with giant cell arteritis also develop a condition that causes inflammation of the muscles called polymyalgia rheumatica.
If you have giant cell arteritis, you therefore may also have symptoms of polymyalgia rheumatica, such as shoulder, neck and hip pain, and muscle stiffness.
Diagnosing giant cell arteritis
If your GP suspects you have giant cell arteritis (GCA), they'll ask you about your symptoms and examine your head.
This is because giant cell arteritis can cause physical signs, such as noticeably swollen arteries in your temples.
If your GP suspects you may have giant cell arteritis, they'll refer you for blood tests to help assess the levels of inflammation inside your body.
Two blood tests that you may have are erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). These tests are useful for assessing conditions associated with short- or long-term inflammation.
If you have vision problems, it's likely your GP will arrange a same-day appointment with an eye specialist (ophthalmologist). This will usually be at your local hospital or eye clinic.
The ophthalmologist will check your eyes for changes associated with giant cell arteritis, such as bleeding or swelling at the site of your optic nerve (the nerve at the back of the eye that transmits signals to the brain).
Temporal artery biopsy
A temporal artery biopsy is most commonly used to test for giant cell arteritis.
During the procedure, the skin on the side of your head is numbed with a local anaesthetic. An incision is made 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.
The sample can be studied under a microscope in a laboratory to check for damage and inflammation of the lining of the arteries. It can take several days to get the results of a biopsy.
If giant cell arteritis is suspected, treatment with steroid medication (corticosteroids) will usually begin immediately. Waiting until the results of the biopsy are known could affect your sight.
Research has shown cranial ultrasound is a simple and accurate diagnostic test for giant cell arteritis. However, the procedure is still quite new and there are only a few rheumatologists in the UK who carry out the technique, so availability is currently limited.
Accurately diagnosing giant cell arteritis is very important because it ensures people with the condition continue to receive steroid treatment to help prevent visual impairment.
This also ensures that those who no longer have the condition don't continue receiving steroid treatment unnecessarily. Long-term steroid use can cause side effects.
Treating giant cell arteritis
Steroid medication (corticosteroids)is the preferred treatment for giant cell arteritis (GCA). A type of steroid medicine called prednisolone is usually prescribed.
If your vision is at risk, you may be given an initial prednisolone injection. After this, prednisolone tablets will be prescribed.
If your vision isn't at risk, you'll be prescribed prednisolone tablets or capsules straight away. You'll probably start on a relatively high dose, which will gradually be 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 treatment. However, there's a chance they'll return (relapse) once treatment stops.
Don't suddenly stop taking steroid medication unless you're told by a doctor that it's safe to do so. Suddenly stopping steroid treatment can make you feel very ill.
About 1 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 aren't there). Contact your GP as soon as possible if you experience changes to your mental state.
Other side effects of prednisolone include:
increased appetite, which often leads to weight gain
increased blood pressure
mood changes, such as becoming aggressive or irritable with people
weakening of the bones (osteoporosis)
increased risk of infection – particularly to the virus that causes chickenpox and shingles (varicella-zoster virus).
Seek immediate medical advice if you think you've 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.
Low-dose aspirin is increasingly being recommended for people with a history of giant cell arteritis. It has been found to be effective in preventing complications of giant cell arteritis, such as heart attacks or stroke.
If you're prescribed steroid medication and low-dose aspirin, another medication called omeprazole may also be recommended. Omeprazole belongs to a class of medicines called proton-pump inhibitors, and it can be used to help protect your stomach from stomach ulcers.
Some people with giant cell arteritis may benefit from treatment with immunosuppressants, such as methotrexate or leflunomide, which are taken along with prednisolone. Omeprazole may also be recommended to help prevent stomach ulcers.
Immunosuppressants are a type of medication used to suppress the immune system (the body's defence against infection and illness). 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're responding to treatment. They'll assess whether your dosage of prednisolone needs to be adjusted and how well you're coping with the side effects of the medication.
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.
During these appointments, you'll have further blood tests to check the levels of inflammation inside your body. If you had a CRP test that indicated high levels of inflammation, you may have another one four weeks after starting steroid treatment.
The second CRP test should show that the inflammation has dropped to normal levels. You may also be referred for scans to assess how strong your bones are.
If you experience a return of your symptoms during any part of your treatment, contact your doctor as your dosage may need to be adjusted.
If you need to take steroids for more than three weeks, your GP or pharmacist should arrange for you to be issued with a steroid card.
It's important to carry the steroid card with you at all times as it will explain that you're regularly taking steroids and your dose shouldn't suddenly be stopped.
This information may prove very important for healthcare professionals who need to treat you in the event of a sudden illness, accident, or emergency.
Complications of giant cell arteritis
People with giant cell arteritis (GCA) can sometimes develop further problems associated with the condition.
Around one in five people with giant cell arteritis will experience some degree of visual loss. This can range from some vision loss in one eye to total blindness.
Coming to terms with any degree of sight loss can be overwhelming, and you'll probably require a great deal of help and support.
You may find it useful to contact the Royal National Institute of Blind People (RNIB), the UK's leading charity for people affected by visual impairment.
Abdominal aortic aneurysm
Inflammation associated with giant cell arteritis can sometimes weaken the walls of the abdominal aorta. This is the main blood vessel responsible for taking blood from the heart and distributing it to the rest of the body.
Weakened walls of the abdominal aorta can cause a bulge to form, known as an aneurysm. An abdominal aortic aneurysm is potentially very serious because there's a risk that the blood vessel could rupture, causing massive internal bleeding and, in most cases, death.
Because of this risk, it may be recommended that you have a check-up every two years if you have a history of giant cell arteritis. Tests such as ultrasound scans and X-rays can be used to check if you have developed an abdominal aortic 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.
People with giant cell arteritis also have an increased risk of developing cardiovascular disease. This is the general term for disease of the heart or blood vessels, and it's a leading cause of stroke and heart attacks.
Treatment for giant cell arteritis, such as low-dose aspirin, can help reduce the risk of cardiovascular disease.