Health The facts about GCA You may never have heard of giant cell arteritis (GCA), but it is the most common form of vasculitis. Read on to find out more Words: PeteR stannett G iant cell arteritis sometimes known as GCA or temporal arteritis is the most common form of vasculitis (inflammation of the blood vessels). However, it is still rare. GCA causes the arteries to narrow, impeding blood flow. It is estimated that one in every 1,200 people develops Polymyalgia Rheumatica (PMR) in the UK each year. Out of every 10 people with PMR, one or two develop GCA. Between 40 and 60 per cent of people with GCA also have PMR, and 16-21 per cent of people with PMR also have GCA. It is unclear why PMR and GCA commonly co-exist. Instances of GCA should be treated as a medical emergency, whether PMR is present or not. Seek medical help immediately if you experience the following symptoms: a headache in one or both temples of a type you have not experienced before; tenderness in the scalp over the temples; blood vessels in the temples that look and feel prominent; vision that is either blurred or double, or you have a temporary or permanent vision loss. In rare cases, you may experience pain in your jaw or tongue. If GCA is present, there is a risk of damage to your eyesight. This can be stopped by early diagnosis and treatment. find out more For more information, call Arthritis Cares free Helpline on 0808 800 4050. Were open Monday to Friday, 09:30-17:00. You can also visit our website here. For more on GCA, click here how is GCA diagnosed? A diagnosis is usually based on symptoms and a physical examination. If GCA is suspected, the doctor may do an ultrasound scan of the arteries in your temple area, as well as a biopsy of a blood vessel in your scalp, under local anaesthetic. Here, asmall sample of the artery is taken and studied under amicroscope. A positive biopsy will show abnormal cells in the artery wall. There is now a fast-track pathway supported by NHS England and pioneered at Southend University Hospital for people who may have GCA. NHS England does not direct Clinical Commissioning Groups to adopt any clinical pathway, but it does make the approach available to clinicians. There is a dedicated phone system that GPs can use, and a rheumatologist will see the patient within 24 hours. how is it treated? Once diagnosed, GCA is treated with a high dose of corticosteroids, which are administered immediately unless the patient has a heart condition. The corticosteroids work by reducing the inflammation in the blood vessels, and the effects can be felt within days. Doses are reduced in steps when symptoms start to disappear and test results indicate an improvement. Roughly a quarter of people with PMR may have a more severe form, meaning that recovery takes longer. The charity Polymyalgia Rheumatica & Giant Cell Arteritis UK suggests a recovery time of three and a half years for those treated with corticosteroids, and most people make a complete recovery. When treated correctly, GCA rarely re-occurs. There is now a fast-track pathway for people who may have GCA