Giant cell arteritis
Giant cell arteritis causes inflammation of the lining of the body's medium and large arteries (vasculitis). The scalp's arteries can be particularly affected.
Symptoms of giant cell arteritis include:
- severe headache
- jaw muscle pain while chewing
- vision loss
Read more about the symptoms of giant cell arteritis.
Giant cell arteritis should be regarded as a medical emergency because without prompt treatment it can lead to permanent blindness in one or both eyes.
How common is giant cell arteritis?
Giant cell arteritis is a fairly uncommon condition. In England, it is estimated that one in every 4,550 people will develop a new case of giant cell arteritis in any given year.
Giant cell arteritis is an age-related condition. It affects only older adults over the age of 50, and usually it is adults over 65 years old who develop it.
Giant cell arteritis is three times more common in women than in men. It is also seven times more common in white people than in black people, with cases being more common in people from Scandinavian countries.
The cause of giant cell arteritis is unclear. However, it is thought that a combination of genetic and environmental factors is responsible for the condition.
Around half of people with giant cell arteritis also develop polymyalgia rheumatica, which is a related but less serious condition. Polymyalgia rheumatica causes inflammation of the muscles and sometimes joints, resulting in symptoms that can include:
- shoulder, neck and hip pain
- stiffness of the affected muscles (which is often present first thing in the morning after waking up before it then improves)
The symptoms of polymyalgia rheumatica can develop before, after or at the same time as the symptoms of giant cell arteritis.
See polymyalgia rheumatica for more information.
If giant cell arteritis is treated before vision loss occurs then the outlook is usually good. The condition responds well to steroid tablets or capsules (oral corticosteroids).
Unfortunately, if any vision loss has already occurred, it is usually permanent and cannot be reversed, although corticosteroids can help prevent any further loss of vision. Developing total blindness is rare and occurs in less than 10% of people with GCA.
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. The long-term use of corticosteroids can lead to a number of troubling side effects, such as:
- weakening of the bones (osteoporosis)
- weight gain
Read more about the treatment of giant cell arteritis.
Symptoms of giant cell arteritis
The symptoms of giant cell arteritis 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.
Headache, jaw pain and vision problems
One of the most common initial symptoms of giant cell arteritis is a headache, which affects two thirds of people with giant cell arteritis. The headache can be severe and sudden and usually affects the side of the head (temples) but can affect the back or the top of the head, or behind the ears. The scalp is often sore to touch, and people notice it is painful to brush their hair.
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.
Experiencing jaw pain when eating and chewing is another symptom of giant cell arteritis, but this affects less than 20% of those with the condition.
Up to one in five people with giant cell arteritis develop vision problems, which usually take 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 which gradually progresses 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 37C-38C (98.6F-100.4F)
- fatigue (extreme tiredness)
- loss of appetite
- weight loss
Less common symptoms of giant cell arteritis include:
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, in practical terms, this can be difficult because the initial symptoms of giant cell arteritis can often be vague and non-specific.
Researches 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 GP immediately if you develop any of these symptoms. If this is not possible, call NHS Direct (0845 45 47) or your local out-of-hours service.
Causes of giant cell arteritis
Giant cell arteritis is due to inflammation in blood vessels, but the cause of this is unknown.
In cases of giant cell arteritis, the temporal arteries are usually most affected.
The temporal arteries run along the side of your head so inflammation there causes pain over the artery. Sometimes arteries to the eye are affected and the optic nerve will lose its blood supply, causing it to fail and leading to a loss of vision.
The fact that giant cell arteritis mainly affects white people seems to suggest that genetics play a role in the condition. Researchers have found that many people with giant cell arteritis have a genetic mutation known as the HLA-DRB1 mutation.
Many researchers believe that another environmental factor such as an infection may trigger giant cell arteritis.
However, as yet there is little evidence to support the role of infection in giant cell arteritis.
Diagnosing giant cell arteritis
If your GP thinks that you may have giant cell arteritis 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.
Your GP will also probably refer you for a series of blood and urine tests, the results of which can be used to assess the levels of inflammation inside your body. These tests can also check how well certain organs in your body, such as your liver and kidneys, are working.
If you have any disturbances to your vision, it is likely that your GP 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 of your face will be numbed with a local anaesthetic. An incision will be made in your skin and a small sample of your temporal artery will be removed. The temporal artery is one of the main blood vessels supplying your skin with blood. 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 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 would still be prescribed steroids.
Treating giant cell arteritis
Steroid medication (corticosteroids) is the preferred treatment for giant cell arteritis. A type of steroid medicine called prednisolone is usually prescribed.
There is currently no alternative medication that is effective in preventing vision loss, or further vision loss, and controlling the symptoms of giant cell arteritis.
If you have symptoms which indicate that your vision might be at risk, your initial treatment may consist of a short course of prednisolone injections. In most cases, this will be three days. After this time, prednisolone tablets will be prescribed for you.
If your symptoms do not suggest that your vision is at risk, you will probably not require a short, initial course of prednisolone injections. In this case, you will be prescribed tablets or capsules straight away.
When you start taking prednisolone tablets you will probably be prescribed 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.
About one in 20 people who take prednisolone will experience changes in their mental state when they take the medication. These changes may include:
- feeling very depressed and suicidal
- feeling manic (very happy and full of energy and ideas)
- feeling very anxious
- feeling very confused
- hallucinations (feeling, seeing or hearing things that are not there)
- having strange and frightening thoughts
Contact your GP as soon as possible if you experience any of the above.
Side effects of prednisolone include:
- increased appetite that often leads to weight gain
- increased blood pressure
- increased risk of infection
- development of high blood sugar (diabetes)
- skin thinning and bruising
- mood changes, such as becoming aggressive or irritable with people
- rapid mood swings, such as feeling very happy one minute and then very sad and tearful the next
- weakening of the bones (osteoporosis)
- muscle weakness (only after prolonged high dose steroids)
The risk of these side effects should improve as your dosage of prednisolone is decreased, although osteoporosis can be a persistent problem, particularly if you are over the age of 65. It can put you at increased risk of fracturing a bone. Most patients are therefore prescribed bisphosphonate tablets to take once a week to reduce the chances of bone thinning (osteoporosis), along with calcium tablets every day except the day you take your bone protection tablet.
Read more about the treatment of osteoporosis.
You may also be referred for a type of scan known as a dual energy X-ray absorptiometry (DEXA) scan, which can help assess how strong your bones are (see diagnosing osteoporosis for more information).
Stomach ulcers can also be a problem for people who are taking high doses of prednisolone on a long-term basis. To protect against stomach ulcers you may also be prescribed a type of medication called a proton pump inhibitors (PPI). This medication will help reduce the amount of acid in your stomach, making you less vulnerable to stomach ulcers. See treating stomach ulcers for more information.
Vulnerability to infection
Prednisolone can also make you more vulnerable to infection, particularly the varicella-zoster virus, which is the virus that causes chickenpox and shingles. You may become very ill if you develop this viral infection. Therefore, avoid close contact with anyone who has a chickenpox or shingles.
Seek immediate medical advice if you think that you have been exposed or if a member of your household develops one of these infections.
Low-dose aspirin is increasingly being recommended as for people who have a history of giant cell arteritis, because this medicine has been found to be effective in preventing complications, such as vision loss or stroke. See complications of giant cell arteritis for more information.
Common side effects of aspirin include:
- stomach or bowel irritation
- nausea (feeling sick)
Your GP will ask you to attend regular follow-up appointments so that 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 a DEXA scan to assess how strong your bones are.
Follow-up appointments are usually recommended on a weekly or bi-weekly 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 GP because your dosage may need to be adjusted.
Complications of giant cell arteritis
Abdominal aorta aneurysm
The inflammation that is associated with giant cell arteritis can sometime 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.
See repair of abdominal aortic aneurysm for more information.
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. You may find it useful to contact the Royal National Institute of Blind People (RNIB), the UK's leading charity for people who are affected by visual impairment.
The RNIB's website also contains a section about living with sight loss which provides a useful range of resources for people who are affected by visual impairment. You can also read more information about living with low vision.