Generality
Horton's arteritis (or giant cell arteritis) is an inflammatory process that affects medium to large caliber arteries. Although it can affect any arterial vessel, inflammation affects the arteries that run through the head, particularly the temples and neck. . Not surprisingly, Horton's arteritis is also known by the third synonym of temporal arteritis.
Figure: a classic sign of Horton's arteritis: swelling of the artery affected by inflammation. From the site: www.medibird.com
If neglected or not treated properly, Horton's arteritis can have unpleasant consequences.
HORTON'S ARTERITIS IS A VASCULITIS
Vasculitis refers to "inflammation of the blood vessels, both arterial and venous. Horton's arteritis is a form of vasculitis limited to arterial vessels."
EPIDEMIOLOGY
As will be seen in the chapter dedicated to risk factors, Horton's arteritis occurs mainly in old age and in women. There seems to be a higher incidence among people from Northern European countries, particularly Scandinavian ones.
Approximately one person in every 4,500 people falls ill with arteritis each year.
Causes
The precise cause that triggers Horton's arteritis is not clear. According to the most accepted hypothesis, the inflammation of the arteries is due to a combination of genetic and environmental factors; therefore, the presence of only one of the two components is not sufficient. to develop the disorder.
N.B: When we talk about environmental factors we refer, in the case of "Horton's arteritis, to infections of viral or bacterial origin.
PATHOLOGICAL ANATOMY
Arteries are flexible tubes, with a thick yet elastic wall. These vessels carry the oxygenated blood that escapes from the left ventricle of the heart, entering the aorta (the main artery of the human body) to then distribute itself into arteries of gradually decreasing diameter up to the capillaries.
When arterial vessels become inflamed, abnormally enlarged and impede normal blood flow. This anatomical change appears to be responsible for the symptoms associated with Horton's arteritis.
RISK FACTORS
Horton's arteritis occurs mainly in individuals suffering from rheumatic polymyalgia. This association, in fact, affects about 15% of patients affected by this last disease, characterized by a "diffuse muscle inflammation, accompanied by pain and muscle stiffness.
The following factors also contribute to the development of Horton's arteritis:
- Advanced age: Arteritis is rare in people under the age of 50-55. It is much more common, however, from the age of 65-70.
- Female gender: Giant cell arteritis is twice as common in women as in men.
- Scandinavian origin: a higher incidence of the disease was noted among the populations of Northern Europe, especially those from Scandinavia. The reason is, however, unknown.
Symptoms and Complications
For further information: Horton's Arteritis Symptoms
Horton's arteritis is characterized by a very varied symptomatology; if in the initial stages it may resemble a flu in some ways, it is distinguished from this by a persistent pain in the head, at the temples. Over time, the flu-like symptoms worsen and, in addition to the headache, there is also a feeling of soreness (always in the temporal area of the skull), loss of vision and pain in the jaw.
Summarizing the symptoms and signs of Horton's arteritis are:
- Headache and a feeling of soreness in the temporal area
- Progressive loss of vision and / or double vision
- Scalp soreness (when combing or resting head on pillow)
- Pain in the jaw, especially when chewing or opening the mouth
- Fever and flu symptoms (tiredness, stiffness and pain in the muscles of the neck, shoulders and hips, etc.)
- Unexplained weight loss
- Swelling and hardening of the affected arteries (temporal ones, in most cases)
PAIN IN THE HEAD OR HEADACHE
Persistent pain in the temples is the main symptom of Horton's arteritis. It usually occurs on both sides, but it cannot be ruled out that it can be one-sided or also affect the forehead.
PAIN IN THE NECK, SHOULDER AND HIP
Their absence, therefore, does not necessarily exclude Horton's arteritis.
WHEN TO SEE THE DOCTOR?
It is essential to pay attention to the ways in which the headache occurs: if this is persistent and accompanied by the other symptoms mentioned above, it deserves further investigation aimed at understanding the reasons for its onset.
To avoid unpleasant problems, it is good to identify Horton's arteritis at the beginning, because it can cause several serious complications, such as blindness.
COMPLICATIONS
There are at least three possible complications related to the appearance of Horton's artertie. The most important is, without doubt, blindness; the other two, less frequent, are aortic aneurysm and stroke.
- Partial and total blindness. It arises due to the swelling, and consequent narrowing, of the arterial vessels that carry oxygenated blood to the eye tissue. In other words, when the blood supply that nourishes the eyes fails, they suffer damage at the cellular level with a dramatic outcome. Vision loss is progressive and, if arteritis is not treated properly, it can become total.
- Aortic aneurysm. As mentioned, Horton's arteritis can affect any arterial vessel of medium and large caliber; the aorta is one of them. Although rare, aortic aneurysm is more common if giant cell arteritis is not treated.
- Stroke. Narrower arterial vessels are more likely to become obstructed by a blood clot. If this happens, a stroke can occur.
Diagnosis
To diagnose Horton's arteritis, specific clinical and instrumental examinations are required, as well as considerable foresight on the part of the doctor. The danger, in fact, is to mistake the symptoms of this inflammation of the arterial vessels for a trivial flu.
Clinical examinations:
- Physical examination
- Blood tests
- Biopsy
Instrumental examinations:
- Nuclear magnetic resonance (MRI)
- Doppler ultrasound (Doppler ultrasound)
- Positron Emission Tomography (PET)
OBJECTIVE EXAMINATION
The doctor, first of all, inquires about the patient's clinical history; in fact, knowing if he is suffering from rheumatic polymyalgia (or symptoms that can be traced back to it) is already a very important indication.
Next, he goes to check the temporal arteries, looking for swelling and other external signs of vascular inflammation.
BLOOD TESTS
If there is a suspicion of Horton's arteritis, the erythrocyte sedimentation test (ESR), performed on the patient's blood, can provide significant information. This test is based on the evaluation of the speed with which the red blood cells settle on the bottom of the tube that contains them. The faster this movement (higher ESR values), the more likely there is an ongoing "inflammation."
Another blood parameter linked to an inflammatory state is the high presence of a particular protein, produced by the liver, known as the C-reactive protein.
Both tests, both that of sedimentation and that of C-reactive protein, are rapid and non-invasive.
BIOPSY
The biopsy is probably the safest clinical exam full of useful information. Performed under local anesthesia, it involves the removal of a small piece of temporal artery and its observation under a microscope.
Figure: Horton's arteritis almost always affects the superficial temporal artery.
From the site: www.vision-and-eye-health.com
On the instrument, the cells of the inflamed arterial vessel appear larger than normal, giant, as the second name of Horton's arteritis says: giant cell arteritis.
There is, however, a small drawback: a tract of a non-inflamed vessel may be removed by mistake and this causes the result of the examination to be negative (even in the presence of the disease). In these cases, then, proceed, taking a second vessel sample, in a different point from the previous one.
THE INSTRUMENTAL EXAMINATIONS
The instrumental tests are used by the doctor both to confirm the diagnosis and to monitor the effects of therapeutic interventions.
- Nuclear magnetic resonance (MRI): by making use of a contrast liquid, it allows the vision of blood vessels and how they change after inflammation. It is by no means an invasive examination.
- Doppler ultrasound (Doppler ultrasound): is, in fact, an "ultrasound of blood vessels. It provides a" detailed image of arteries and veins, without any danger to the patient.
- Positron Emission Tomography (PET): by injecting a radiopharmaceutical into arterial vessels, it is possible to assess whether (and how) their functions have changed after inflammation (or after treatment). It is a mildly invasive procedure, because it uses ionizing radiation.
Treatment
For the treatment of Horton's arteritis, it is necessary to use corticosteroid drugs (for example, prednisone), as they are the only preparations able to stop the inflammation.
HEALING AND MONITORING TIMES
The first effects of the therapy are observed after a few days, even if for complete recovery the treatment must be maintained for at least one or two years.
During this time, the progress of inflammation is monitored by two reliable and easily performed tests: the erythrocyte sedimentation test and the C-reactive protein test. When the above tests are free of anomalies, the patient can be considered cured. If doubts remain, the doctor may request a PET scan.
DOSES
After the first month of therapy, the administered corticosteroid doses are progressively reduced. Once the minimum quantity capable of controlling the inflammation has been established, this is followed until the end of the treatment.
SIDE EFFECTS
Side effects of corticosteroid treatment:
- Osteoporosis
- Hypertension (high blood pressure)
- Muscle weakness
- Glaucoma
- Cataract
- Weight gain
- Diabetes (blood glucose levels increase)
- Sensitive skin and easy bruising
- Weakening of the immune system
Corticosteroids are very powerful and effective anti-inflammatory drugs, which however can cause numerous side effects, especially when taken for a long time.
TIPS TO FOLLOW
During the treatment, to keep under control the side effects related to corticosteroids, it is good to follow some advice.
First of all, it becomes essential to correct the diet, so as not to favor the rise in blood pressure and blood sugar (glucose in the blood). Therefore, table salt should be moderate and fatty foods, sweets, sugars and alcohol, in favor of fruits, vegetables, whole grains and lean meat / fish.
Secondly, it is very useful to take calcium and vitamin D supplements against osteoporosis.
Finally, if age permits, it is important to stay active in order to promote bone turnover and limit weight gain and muscle tone reduction.
Prognosis
Horton's arteritis, if diagnosed early and treated correctly, resolves in a more than positive way.
On the contrary, a late diagnosis and / or an approximate cure can affect, even significantly, the recovery process, thus making the prognosis negative.
For a positive prognosis of Horton's arteritis, the following are important:
- Early diagnosis
- Immediate corticosteroid drug therapy
- Adequate diet
- Keep active
- Intake of calcium and vitamin D.
