Aortitis: inflammation of the aorta, its causes, tests and treatment

The aorta is the largest artery in the body. It leaves the heart, arches over and runs down through the chest and abdomen, with branches supplying the head, arms, organs and legs. Aortitis means that the wall of the aorta is inflamed. Inflammation can thicken, weaken or narrow the wall, which is why it is investigated carefully even when symptoms are vague.

Aortitis is not usually a stand-alone disease. It is a feature of other conditions. Vasculitis UK describes Takayasu arteritis as a form of large vessel vasculitis in which inflammation occurs in the large arteries, particularly the aorta (the main artery taking blood from the heart to the rest of the body) and its main branches. The same charity and the NHS describe giant cell arteritis (temporal arteritis), a related large vessel vasculitis. Both are covered here because they are the conditions most often discussed under this heading in UK patient information.

No UK patient leaflet devoted only to aortitis was available when this page was prepared, so the information below draws on UK charity and NHS pages for the conditions that cause it.

The main groups of causes are inflammatory (autoimmune) conditions affecting blood vessels, and infections. Vasculitis UK says the cause of Takayasu arteritis is unknown, and that it is most likely the consequence of environmental factors and a susceptible genetic background, with one common but unproven hypothesis being that it is precipitated by an infection. It describes the inflammation as white blood cells invading the wall of the artery, predisposing to damage and scarring.

For giant cell arteritis, Vasculitis UK says the cause is not yet known. It describes the condition as inflammation of large and medium sized blood vessels, with the blood vessels in the temples commonly affected.

Infection is a further cause. The NHS lists heart problems such as angina, aortic aneurysm and heart failure among the complications of untreated syphilis, and says that some of these problems may not appear for many years after infection. That is a reason that untreated infection is considered when the aorta is found to be inflamed or enlarged.

Symptoms depend on the underlying cause and on which arteries are affected. Vasculitis UK says the initial symptoms of Takayasu arteritis are typically non-specific and may include malaise, profound fatigue, fever, night sweats, weight loss, muscle pain, joint pain and rash. Additional symptoms can include dizziness or light-headedness, shortness of breath, and cramping pain in the arms, legs or chest on exertion. Pain and tenderness over the carotid arteries in the front of the neck is found in approximately 25 per cent of patients.

For giant cell arteritis, the NHS lists frequent severe headaches, pain or tenderness at the temples or scalp, jaw pain while eating or talking, and vision problems such as double vision or loss of vision in one or both eyes. More general symptoms such as flu-like symptoms, unintentional weight loss, depression and tiredness are also common, and some people also develop polymyalgia rheumatica.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if you think you might have temporal arteritis, because it can lead to serious problems like stroke and blindness if not treated quickly. If you have vision problems, it says you should have a same-day appointment with an eye specialist at a hospital eye department.

Sudden severe chest or back pain, collapse, new weakness down one side or sudden loss of vision are emergencies and should be treated as 999 situations.

Vasculitis UK says that for Takayasu arteritis there is no single test. Diagnosis is made on the basis of formal criteria, and in practice clinical examination most commonly detects decreased or absent pulses in the arms, a difference in blood pressure between the arms, or bruits (a whooshing noise heard with a stethoscope) over narrowed arteries. High blood pressure is commonly found. Blood tests for ESR and CRP help measure inflammation, but there is no blood test that definitively confirms the diagnosis.

Imaging is central. Vasculitis UK lists positron emission tomography (PET), magnetic resonance angiography (MRA), high-resolution ultrasound and CT angiography, and says patients typically have a series of scans at diagnosis and more at regular intervals for follow-up, because none of them is 100 per cent accurate on its own.

For giant cell arteritis, the NHS says a GP will ask about symptoms, examine the temples and arrange blood tests before referral to a specialist, who may arrange an ultrasound scan of the temples or a biopsy of the temporal artery under local anaesthetic.

Treatment aims to control inflammation and protect organs. For giant cell arteritis, the NHS says treatment is with steroid medicine, usually prednisolone, started before the diagnosis is confirmed because of the risk of vision loss. There are two stages: an initial high dose for a few weeks and then a lower dose over a longer period, possibly several years, and a small number of people need to take steroids for life. The NHS warns not to stop steroids suddenly unless a doctor says so.

It also lists medicines that may be added: low-dose aspirin to reduce the risk of stroke or heart attack, a proton pump inhibitor to protect the stomach, bisphosphonate therapy to reduce the risk of osteoporosis, and immunosuppressants to allow the steroid dose to be reduced. Vasculitis UK says other drugs such as methotrexate, azathioprine or antibody therapy are sometimes used in resistant disease.

Vasculitis UK notes that in some people with Takayasu arteritis part of an artery enlarges to form an aneurysm, so imaging follow-up also looks at vessel size, and any procedure is an individual decision for the specialist team.

These are long-term conditions managed by hospital specialists, often rheumatologists, with regular follow-up and repeat imaging. The NHS says people with temporal arteritis have regular follow-ups to see how they are doing and to check for side effects of treatment.