Giant Cell Arteritis - Temporal Arteritis
What is it?
This is a disease characterised by inflammation("itis") of large and medium
sized blood vessels ("arteries"), with infiltration of small and large blood
cells ("giant cell"). An alternative name for this condition is
"temporal arteritis" as the blood vessels in the temple area of the head are
commonly affected.
Who Are Affected?
This condition is relatively rare, and affects only 1-2 persons per 10,000 people.
This condition is more commonly seen in elderly, and is seldom diagnosed below the age of
50. For some unknown reason, this condition affects the white population almost
exclusively.
What Are The Symptoms?
Non-specific features of fatigue, loss of appetite, weight loss and fever are often found.
Headache is a prominent feature of this disease due to inflammation of the temporal
vessels. GCA is closely associated with the "Polymyalgia Rheumatica Syndrome",
which presents as general weakness, pain and stiffness in muscles and joints. The
weakness in the muscles can be quite debilitating and typically affects the upper arms and
legs. Simple tasks such as brushing the hair, cooking, gardening, getting up and out
of chairs or beds and walking may now become difficult.
As this condition affects blood vessels with inflammation, a reduction in
the oxygen supply (ischeamia) to different organs can result. Depending on the organ
supplied by the diseased vessels, a great variety of symptoms can result. A classic
symptom of this condition is jaw and tongue pain due to lack of oxygen supply. In
the heart, a heart attack can result; and starving the brain of blood can lead to a
stroke. Reduction in the oxygen supply to the eyes can lead to blurred vision, or in
some patients, blindness.
Aetiology/Cause
An infectious trigger has been suggested but no definite infectious organism has been
found consistently in patients. The predominance in the white population, cluster of
cases in some families and the association with some genes called HLA-DR4 favour an
inherited predisposition to the disease.
Diagnosis
The inflammation in the blood will be reflected in certain blood markers. One such
marker which is always raised in this condition is called an "ESR", and can be
measured by taking a blood sample. Unfortunately other conditions such as infections
can also cause an ESR rise and so diagnosis is not solely made on the basis of the ESR
result.
The gold standard for diagnosis is a biopsy of the temporal artery.
The inflammation in the blood vessels is not uniformly present and sections of the blood
vessels can still be normal. Hence, a positive biopsy showing inflammation confirms
disease but a negative biopsy does not exclude disease.
Treatment
The aim of treatment is to relieve the patient of troublesome symptoms and prevent
ischaemic symptoms due to lack of oxygen. Most symptoms resolve with treatment.
High dose oral steroids in the form of prednisolone is usually given and the dose
is tapered over months, using the ESR marker as a guide to response. Treatment with
steroids is given for at least 1-2 years.
Side Effects?
Yes. Steroids work by suppressing inflammation, but also suppresses the body's
ability to fight infection. Steroids will accelerate the natural process of bone
thinning, and fractures can occur. Steroids can also cause or aggravate indigestion,
sugar diabetes, high blood pressure, thinning and bruising of the skin and weight gain.
Although most patients will be taking steroids for years, the dose is reduced
quickly to prevent side effects. Patients will be seen regularly and dose of
steroids taken is not sufficient in most patients to cause these side effects.
Can this Condition Relapse?
Yes. In about 50% of patients, withdrawal of steroid can lead to a relapse of
symptoms. In such cases, the steroid is re-started and it is often sufficient to
induce remission with a much lower dose. After achieving remission, the steroid dose
can again be reduced. In most relapsed cases, the patients will be maintained on a
small dose of steroid indefinitely.
Prognosis
Good, with correct early diagnosis and treatment.
Acknowledgements
Dr. Wai Tse
The University of Birmingham Medical School.
Prof. Caroline Savage
Senior Lecturer (Nephrology) The University of Birmingham Medical School.
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