Giant cell arteritis
GIANT CELL ARTERITIS (GCA) / TEMPORAL ARTERITIS
Temporal arteritis or giant cell arteritis (GCA) is an autoimmune disease where our white blood cells mistakenly attack our own cells in our arteries. The inflammation causes the artery walls to swell which narrows the channel for blood to flow and can cause blockage of affected arteries. The major arteries of the body are affected, including temporal arteries which lead to tenderness over the temple area.
In GCA, if the artery that supply blood to the eye become affected then it can cause blindness. It can also cause double vision if nerves supplying the muscles of the eye are affected. It is therefore a serious disease that eye specialists are trained to diagnose.
What causes GCA?
The exact cause of temporal arteritis is not known, but it affects predominantly patients over 50 years of age. It is also more common women.
Patient with GCA can also have symptoms of polymyalgia rheumatica, a condition
causing muscle pain and stiffness again due to inflammation.
What are the symptoms of GCA?
To diagnose GCA is often difficult because symptoms can be mild or absent and not occur until late in the course of the disease.
Common symptoms include:
a new headache, especially over the temples
pain in the jaw muscles while chewing
low grade temperature
scalp tenderness, especially over the temples
swollen arteries over the temples
disturbances of vision, such as a curtain in the field of vision, double vision, or loss of vision
poor appetite and weight loss
aching and stiffness of shoulders and hips.
Less common symptoms include: cramping or aching in the arms or legs when exercising, relieved by resting, stroke-like symptoms, hearing your own pulse in the neck, armpits, or groins, widening of arteries called aneurysm, including of the main aorta.
How is GCA diagnosed?
Diagnosis is based on the symptoms and an examination looking for the symptom and signs above and supported by laboratory tests. The tests include blood tests called ESR and CRP to look for inflammation and a biopsy of the temporal artery showing inflammation.
The blood tests ESR and CRP however are not specific to GCA and can also be caused by inflammation or infection elsewhere in the body. Therefore biopsy of temporal artery is often required.
How is GCA treated?
Like all inflammatory conditions, GCA is treatable with steroids (usually prednisolone) which
damp down inflammation. A small daily dose of 75mg aspirin can also help to keep the arteries
flowing. It is usual to need up to two years of the drug treatment, sometimes longer.
Having a positive biopsy is helpful because doctors are reluctant to prescribe steroids without good reason due to their side effects. These include weight gain, diabetes, blood pressure,
thinning of the bones and skin, cataracts, and psychiatric problems, amongst others. However, because of the potentially serious consequences of the disease, your eye doctor usually will start steroids as soon as the diagnosis is suspected and before a biopsy can be arranged. Biopsy needs to be done as soon as possible because the chance of a positive result drops quickly after only a couple of weeks on steroids.
What is a temporal artery biopsy?
Temporal artery biopsy is a small procedure to remove a ~2cm piece of a temporal artery for investigation in the pathology department. Under the microscope the pathologist is able to examine for inflammation characteristic of GCA. The procedure is usually done under local anaesthetic, an injection in the skin over the artery to make the skin numb and painless. Your eye specialist may need to shave a little hair from the temple region.
What happens before the biopsy?
Before the procedure you can should eat and drink as normal. You should
take any medications as usual unless specifically asked to stop, for example, blood thinners such as or asprin warfarin which you will start again after the operation.
How long will the biopsy take?
You will go home just an hour or so after the surgery which usually takes only 30 to 60 minutes, occasionally longer if the artery is difficult to find.
What happens during the biopsy?
Once in the operating theatre, when the skin is numb and has been cleaned with antiseptic, a cut is made along the artery on the temple sufficient to remove the necessary 2cm piece. The cut ends of the artery left behind are tied off to prevent bleeding and the cut skin is closed
dissolvable suture before a dressing is applied.
What happens after the biopsy?
It is a good idea to have someone to help you home as some can feel shaky even after a
simple operation. Once at home, you should continue with life as normal, including taking your
medications and the prednisolone, but taking care when washing your face and hair for a week or so until the cut has healed.
You will be given an antibiotic ointment to apply to the wound to prevent infection.
The result from the laboratory will generally be available on your next visit.
How will I feel after the procedure?
The cut is not usually very painful afterwards but you should take a mild painkiller, such as
paracetamol, if needed for this or any headache. You may apply ice pack over the area for the first 1-2 days to reduce pain and swelling.
What are the risks of the operation?
Temporal artery biopsy is generally a safe procedure but, like all medical interventions, carries a
small risk of complications and will leave a scar. Possible complications include:
wound infection - if the wound becomes more red and swollen or develops a discharge, you may need an antibiotic from your doctor
bleeding may happen soon after or later with an infection and should be controlled by applying pressure then a clean dressing once stopped; blood-thinning drugs, such as aspirin, clopidogrel, warfarin, or other anticoagulants make this more likely
nerve injury – temporary or permanent damage to unseen nerves around the temple which can produce numbness or a drooping brow, this is rare.
Very rarely would biopsy of temporal artery lead to serious complications such as stroke.