It is more common in women than in men by a ratio of 2:1 and more common in those of Northern European descent, as well as those residing at higher (northern/southern) latitudes. The mean age of onset is >55 years, and it is rare in those younger than 55 years of age.

People present with:

- bruits

- fever

- headache

- tenderness and sensitivity on the scalp

- jaw claudication (pain in jaw when chewing)

- tongue claudication (pain in tongue when chewing) and necrosis

- reduced visual acuity (blurred vision)

- acute visual loss (sudden blindness)

- diplopia (double vision)

- acute tinnitus (ringing in the ears)

- polymyalgia rheumatica (in 50%)

The inflammation may affect blood supply to the eye; blurred vision or sudden blindness may occur. In 76% of cases involving the eye, the ophthalmic artery is involved causing arteritic anterior ischemic optic neuropathy.

Giant-cell arteritis may present with atypical or overlapping features. Early and accurate diagnosis is important to prevent ischemic vision loss. Therefore, this condition is considered a medical emergency.

Symptoms of general arteritis may include:

- Inflammation

- Fever

- Increased production of red blood cells (erythrocytes)

- Limping

- Reduced pulse

The varicella-zoster virus antigen was found in 74% of temporal artery biopsies that were GCA-positive, suggesting that the VZV infection may trigger the inflammatory cascade.

The disorder may coexist (in a half of cases) with polymyalgia rheumatica (PMR), which is characterized by sudden onset of pain and stiffness in muscles (pelvis, shoulder) of the body and is seen in the elderly. GCA and PMR are so closely linked that they are often considered to be different manifestations of the same disease process. Other diseases associated with temporal arteritis are systemic lupus erythematosus, rheumatoid arthritis, and severe infections.

Giant-cell arteritis can involve branches of the aorta as well, leading to an aortic aneurysm or dissection. For this reason, patients should be followed with serial chest X-rays.

Temporal arteritis, the second type of giant cell arteritis, is also a chronic, inflammatory disease involving mid- to large-sized arteries. Temporal arteritis has a higher incidence in people of Scandinavian descent. However, the incidence rate differs based on population, region and races. Temporal arteritis is not uncommon in North America. The incidence rate is around 0.017% for individuals over 50 years of age.

Symptoms of temporal arteritis are classified as specific and nonspecific.

Nonspecific symptoms:

- Headache

- Low grade fever

- Sweating

- Anorexia (loss of appetite)

- Weight loss

- General malaise

Specific symptoms:

- Claudication of the jaw

- Engorged, tender vessels

Specific symptoms usually develop in the advanced stages of temporal arteritis.

Polyarteritis nodosa of unknown mechanism can cause testiscular pain. It is often associated with aneurysms and Hepatitis B.

Giant-cell arteritis and Takayasu's arteritis have much in common, but usually affect patients of different ages, with Takayasu's arteritis affecting younger people, and giant-cell arteritis having a later age of onset.

Aortitis can also be considered a large-vessel disease.

Takayasu arteritis. Primarily affects the aorta and its main branches. At least 3 out of 6 criteria yields sensitivity and specificity of 90.5 and 97.8%:

- onset < 40 years affects young and middle -aged women (ages 15–45)

- claudication of extremities

- decreased pulsation of one or both brachial arteries

- at least 10 mmHg systolic difference in both arms

- bruit over one or both carotid arteries or abdominal aorta

- arteriographic narrowing of aorta, its primary branches, or large arteries in upper or lower extremities

- Ocular manifestation

- visual loss or field defects

- Retinal hemorrhages

- Neurological abnormalitis

- Treatment: steroids

Giant cell (temporal) arteritis. Chronic vasculitis of both large and medium vessels, primarily affecting cranial branches of the arteries arising from the aortic arch. At least 3 out of 5 criteria yields sensitivity and specificity of 95 and 91%:

- Age at onset ≥ 50 years

- New onset headache with localized tenderness

- Temporal artery tenderness or decreased pulsation

- Elevated ESR ≥ 50 mm/hour Westergren

- Temporal artery biopsy showing vasculitis with mononuclear cell infiltrate or granulomatous inflammation, usually with multinucleated giant cells

These conditions are sometimes considered together with the small vessel vasculitides.

Polyarteritis nodosa (PAN). Systemic necrotizing vasculitis and aneurysm formation affecting both medium and small arteries. If only small vessels are affected, it is called microscopic polyangiitis, although it is more associated with granulomatosis with polyangiitis than to classic PAN. At least 3 out of 10 criteria yields sensitivity and specificity of 82 and 87%:

- unexplained weight loss > 4 kg

- livedo reticularis

- testicular pain

- myalgias, weakness

- Abdominal pain, diarrhea, and GI bleeding

- mononeuropathy or polyneuropathy

- new onset diastolic blood pressure > 90 mmHg

- elevated serum BUN (> 40 mg/dL) or serum creatinine (> 1.5 mg/dL)

- hepatitis B infection

- arteriographic abnormalities

- arterial biopsy showing polymorphonuclear cells

Kawasaki disease. Usually in children(age<4), it affects large, medium, and small vessels, prominently the coronary arteries. Associated with a mucocutaneous lymph node syndrome. Diagnosis requires fever lasting five days or more with at least 4 out of 5 criteria:

- bilateral conjunctival injection

- injected or fissured lips, injected pharynx, or strawberry tongue

- erythema of palms/soles, edema of hands/feet, periungual desquamation

- polymorphous rash

- cervical lymphadenopathy (at least one node > 1.5 cm)

Isolated cerebral vasculitis. Affects medium and small arteries over a diffuse CNS area, without symptomatic extracranial vessel involvement. Patients have CNS symptoms as well as cerebral vasculitis by angiography and leptomeningeal biopsy.

Affected individuals typically present with sudden painful proptosis, redness, and edema. Proptosis will vary according to the degree of inflammation, fibrosis, and mass effect. Occasionally, ptosis, chemosis, motility dysfunction (ophthalmoplegia), and optic neuropathy are seen. In the setting of extensive sclerosis there may be restriction, compression, and destruction of orbital tissue. Symptoms usually develop acutely (hours to days), but have also been seen to develop over several weeks or even months.Malaise, headaches, and nausea may accompany these symptoms. Other unusual presentations described include cystoid macular edema, temporal arteritis, and cluster headaches.

Pediatric IOI accounts for about 17% of cases idiopathic orbital inflammation. The most common sign is proptosis, but redness and pain are also experienced. Presentation varies slightly compared to adults with bilateral involvement, uveitis, disc edema and tissue eosinophilia being more common in this population. The presence of uveitis generally implies a poor outcome for pediatric IOI. Bilateral presentation may have a higher incidence of systemic disease.

A wide range of symptoms can indicate if a person has polymyalgia rheumatica. The classic symptoms include:

- Pain and stiffness (moderate to severe) in the neck, shoulders, upper arms, thighs, and hips, which inhibits activity, especially in the morning/after sleeping. Pain can also occur in the groin area and in the buttocks. The pain can be limited to one of these areas as well. It is a disease of the "girdles" meaning shoulder girdle or pelvic girdle.

- Fatigue and lack of appetite (possibly leading to weight loss) are also indicative of polymyalgia rheumatica.

- Anemia

- An overall feeling of illness or flu-like symptoms.

- Low-grade (mild) fever or abnormal temperature is sometimes present.

- In most people, it is characterized by constant fatigue, weakness and sometimes exhaustion.

About 15% of people who are diagnosed with polymyalgia rheumatica also have temporal arteritis, and about 50% of people with temporal arteritis have polymyalgia rheumatica. Some symptoms of temporal arteritis include headaches, scalp tenderness, jaw or facial soreness, distorted vision, or aching in the limbs caused by decreased blood flow, and fatigue.

Possible symptoms include:

- General symptoms: Fever, weight loss

- Skin: Palpable purpura, livedo reticularis

- Muscles and joints: Myalgia or myositis, arthralgia or arthritis

- Nervous system: Mononeuritis multiplex, headache, stroke, tinnitus, reduced visual acuity, acute visual loss

- Heart and arteries: Myocardial infarction, hypertension, gangrene

- Respiratory tract: Nose bleeds, bloody cough, lung infiltrates

- GI tract: Abdominal pain, bloody stool, perforations

- Kidneys: Glomerulonephritis

Some people develop an initial "inflammatory phase" characterized by systemic illness with signs and symptoms of malaise, fever, night sweats, weight loss, joint pain, fatigue, and fainting. Fainting may result from subclavian steal syndrome or carotid sinus hypersensitivity. There is also often anemia and marked elevation of the ESR or C-reactive protein (nonspecific markers of inflammation). The initial "inflammatory phase" is often followed by a secondary "pulseless phase". The "pulseless phase" is characterized by vascular insufficiency from intimal narrowing of the vessels manifesting as arm or leg claudication, renal artery stenosis causing hypertension, and neurological manifestations due to decreased blood flow to the brain.

Of note is the function of renal artery stenosis in the causation of high blood pressure: Normally perfused kidneys produce a proportionate amount of a substance called renin. Stenosis of the renal arteries causes hypoperfusion (decreased blood flow) of the juxtaglomerular apparatus, resulting in exaggerated secretion of renin, and high blood levels of aldosterone, eventually leading to water and salt retention and high blood pressure. The neurological symptoms of the disease vary depending on the degree; the nature of the blood vessel obstruction; and can range from lightheadedness to seizures (in severe cases). One rare, important feature of the Takayasu's arteritis is ocular involvement in form of visual field defects, vision loss, or retinal hemorrhage. Some individuals with Takayasu's arteritis may present with only late vascular changes, without a preceding systemic illness. In the late stage, weakness of the arterial walls may give rise to localized aneurysms. As with all aneurysms, the possibility of rupture and vascular bleeding is existent and requires monitoring. In view of the chronic process and good collateral development, Raynaud's phenomenon or digital gangrene are very rare in Takayasu arteritis. A rare complication of this condition are coronary artery aneurysms.

Idiopathic orbital inflammatory (IOI) disease, or orbital pseudotumor, refers to a marginated mass-like enhancing soft tissue involving any area of the orbit. It is the most common painful orbital mass in the adult population, and is associated with proptosis, cranial nerve (Tolosa–Hunt syndrome), uveitis, and retinal detachment. Idiopathic orbital inflammatory syndrome, also known as orbital pseudotumor, was first described by Gleason in 1903 and by Busse and Hochhmein. It was then characterized as a distinct entity in 1905 by Birch-Hirschfeld. It is a benign, nongranulomatous orbital inflammatory process characterized by extraocular orbital and adnexal inflammation with no known local or systemic cause. Its diagnosis is of exclusion once neoplasm, primary infection and systemic disorders have been ruled-out. Once diagnosed, it is characterized by its chronicity, anatomic location or histologic subtype.

Idiopathic orbital inflammation has a varied clinical presentation depending on the involved tissue. It can range from a diffuse inflammatory process to a more localized inflammation of muscle, lacrimal gland or orbital fat. Its former name, orbital pseudotumor, is derived due to resemblance to a neoplasm. However, histologically it is characterized by inflammation. Although a benign condition, it may present with an aggressive clinical course with severe vision loss and oculomotor dysfunction.

Takayasu's arteritis (also known as Takayasu's disease, "aortic arch syndrome," "nonspecific aortoarteritis," and "pulseless disease") is a form of large vessel granulomatous vasculitis with massive intimal fibrosis and vascular narrowing, most commonly affecting often young or middle-age women of Asian descent, though anyone can be affected. It mainly affects the aorta (the main blood vessel leaving the heart) and its branches, as well as the pulmonary arteries. Females are about 8–9 times more likely to be affected than males.

Those with the disease often notice symptoms between 15 and 30 years of age. In the Western world, atherosclerosis is a more frequent cause of obstruction of the aortic arch vessels than Takayasu's arteritis. Takayasu's arteritis is similar to other forms of vasculitis, including giant cell arteritis which typically affects older individuals. Due to obstruction of the main branches of the aorta, including the left common carotid artery, the brachiocephalic artery, and the left subclavian artery, Takayasu's arteritis can present as pulseless upper extremities (arms, hands, and wrists with weak or absent pulses on the physical examination) which may be why it is also commonly referred to as the "pulseless disease." Involvement of renal arteries may lead to a presentation of renovascular hypertension.

Retinal vasculitis is very rare as the only presenting symptom. Often there is sufficient systemic evidence to help the physician decide between any one of the aforementioned possible systemic diseases. For those patients who present with only vasculitis of the retinal vessels, great investigative effort (Chest X-ray, blood test, urinary analysis, vascular biopsy, ophthalmology assessment, etc.) should be undertaken to ensure that a systemic disease is not the hidden culprit.

Vasculitis can be classified by the cause, the location, the type of vessel or the size of vessel.

- "Underlying cause". For example, the cause of syphilitic aortitis is infectious (aortitis simply refers to inflammation of the aorta, which is an artery.) However, the causes of many forms of vasculitis are poorly understood. There is usually an immune component, but the trigger is often not identified. In these cases, the antibody found is sometimes used in classification, as in ANCA-associated vasculitides.

- "Location of the affected vessels". For example, ICD-10 classifies "vasculitis limited to skin" with skin conditions (under "L"), and "necrotizing vasculopathies" (corresponding to systemic vasculitis) with musculoskeletal system and connective tissue conditions (under "M"). Arteritis/phlebitis on their own are classified with circulatory conditions (under "I").

- "Type or size of the blood vessels" that they predominantly affect. Apart from the arteritis/phlebitis distinction mentioned above, vasculitis is often classified by the caliber of the vessel affected. However, there can be some variation in the size of the vessels affected.

According to the size of the vessel affected, vasculitis can be classified into:

- Large vessel: Polymyalgia rheumatica, Takayasu's arteritis, Temporal arteritis

- Medium vessel: Buerger's disease, Kawasaki disease, Polyarteritis nodosa

- Small vessel: Behçet's syndrome, Eosinophilic granulomatosis with polyangiitis, Cutaneous vasculitis, Henoch–Schönlein purpura, Microscopic polyannulomatosis ConditionofSome disorders have vasculitis as their main feature. The major types are given in the table below:

Takayasu's arteritis, polyarteritis nodosa and giant cell arteritis mainly involve arteries and are thus sometimes classed specifically under arteritis.

Furthermore, there are many conditions that have vasculitis as an accompanying or atypical feature, including:

- Rheumatic diseases, such as rheumatoid arthritis, systemic lupus erythematosus, and dermatomyositis

- Cancer, such as lymphomas

- Infections, such as hepatitis C

- Exposure to chemicals and drugs, such as amphetamines, cocaine, and anthrax vaccines which contain the Anthrax Protective Antigen as the primary ingredient.

In pediatric patients varicella inflammation may be followed by vasculitis of intracranial vessels. This condition is called post varicella angiopathy and this may be responsible for arterial ischaemic strokes in children.

Several of these vasculitides are associated with antineutrophil cytoplasmic antibodies. These are:

- Granulomatosis with polyangiitis (formerly known as Wegener's granulomatosis)

- Eosinophilic granulomatosis with polyangiitis (formerly known as Churg-Strauss syndrome)

- Microscopic polyangiitis

Retinal vasculitis presents as painless, decrease of visual acuity (blurry vision), visual floaters, scotomas (dark spot in vision), decreased ability to distinguish colors, and metamorphopsia (distortion of images such as linear images).

Polymyalgia rheumatica (PMR) is a syndrome with pain or stiffness, usually in the neck, shoulders, upper arms, and hips, but which may occur all over the body. The pain can be very sudden, or can occur gradually over a period. Most people with PMR wake up in the morning with pain in their muscles; however, cases have occurred in which the person has developed the pain during the evenings or has pain and stiffness all day long. People who have polymyalgia rheumatica may also have temporal arteritis, an inflammation of blood vessels in the face which can cause blindness if not treated quickly. The pain and stiffness can result in a lowered quality of life, and can lead to depression.

Polymyalgia rheumatica is often seen in association with temporal arteritis. It is thought to be brought on by a viral or bacterial illness or trauma of some kind, but genetics does play a factor as well. Persons of Northern European descent are at greater risk. There is no definitive laboratory test, but C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) can be useful.

PMR is usually treated with corticosteroids taken by mouth. Most people need to continue the corticosteroid treatment for two to three years. PMR sometimes goes away on its own in a year or two, but medications and self-care measures can improve the rate of recovery.

PMR was first established as a distinct disease in 1966 by a case report on 11 patients at Mount Sinai Hospital in New York, NY. It takes its name from the Greek word Πολυμυαλγία "polymyalgia" which means "pain in many muscles".

There are several constitutional symptoms of temporal arteritis that may aid in diagnosis of AAION such as jaw claudication (spasms of the jaw muscle), scalp tenderness, unintentional weight loss, fatigue, myalgias and loss of appetite. However, many cases are asymptomatic. There are also elevations in three blood tests that help identify AAION: erythrocyte sedimentation rate (ESR), C reactive protein (CRP) and platelet count (thrombocytosis). A related rheumatic disease called polymyalgia rheumatica has a 15 percent incidence of giant cell arteritis.

This inflammation has a number of possible causes, including trauma, viral or bacterial infections (notably, syphilis), and certain immune disorders and connective tissue diseases.

Aortitis is most commonly seen in patients with syphilis, autoimmune vasculitis (giant cell arteritis, Takayasu's arteritis), polymyalgia rheumatica, and rheumatoid arthritis. IgG4-related disease has more recently been identified as a cause of aortitis, and also as a cause of periaortitis (inflammation "surrounding" the aorta).

There is a wide range of symptoms that are dependent on the location of the aortic inflammation or associated disorder. A few symptoms recognized in patients are fever, chills, muscle pains, and malaise (general discomfort). In addition, hypertension (high blood pressure) may occur. Hypertension happens when the renal artery narrows and elasticity of the aorta and branches decrease.

Arteritic anterior ischemic optic neuropathy (AAION or arteritic AION) is the cause of vision loss that occurs in temporal arteritis (aka giant cell arteritis). Temporal arteritis is an inflammatory disease of medium-sized blood vessels that happens especially with advancing age. AAION occurs in about 15-20 percent of patients with temporal arteritis. Damage to the blood vessels supplying the optic nerves leads to insufficient blood supply (ischemia) to the nerve and subsequent optic nerve fiber death. Most cases of AAION result in nearly complete vision loss first to one eye. If the temporal arteritis is left untreated, the fellow eye will likely suffer vision loss as well within 1–2 weeks. Arteritic AION falls under the general category of anterior ischemic optic neuropathy, which also includes non-arteritic AION. AION is considered an eye emergency, immediate treatment is essential to rescue remaining vision.

An exhaustive review article published in March 2009 described the latest information on arteritic and non-arteritic ischemic optic neuropathy, both anterior (A-AION and NA-AION) and posterior (A-PION, NA-PION, and surgical).

Aortitis is the inflammation of the aortic wall. The disorder is potentially life-threatening and rare. It is reported that there are only 1–3 new cases of aortitis per year per million people in the United States and Europe. Aortitis is most common in people 10 to 40 years of age.

Obliterating endarteritis also called "obliterating arteritis" is severe proliferating endarteritis (inflammation of the intima or inner lining of an artery) that results in an occlusion of the lumen of the artery. Obliterating endarteritis can occur due to a variety of medical conditions such as a complication of radiation poisoning, tuberculosis meningitis or a syphilis infection.

Carotidynia is a syndrome characterized by unilateral (one-sided) tenderness of the carotid artery, near the bifurcation. It was first described in 1927 by Temple Fay. The most common cause of carotidynia may be migraine, and then it is usually self-correcting. Common migraine treatments may help alleviate the carotidynia symptoms. Recent histological evidence has implicated an inflammatory component of carotidynia, but studies are limited. Carotid arteritis is a much less common cause of carotidynia, but has much more serious consequences. It is a form of giant cell arteritis, which is a condition that usually affects arteries in the head. Due to this serious condition possibly causing carotidynia, and the possibility that neck pain is related to some other non-carotidynia and serious condition, the case should be investigated by a medical doctor. Because carotidynia can be caused by numerous causes, Biousse and Bousser in 1994 recommended the term not be used in the medical literature. However, recent MRI and ultrasound studies have supported the existence of a differential diagnosis of carotidynia consistent with Fay's characterization.

Amaurosis fugax (Latin "" meaning "fleeting", Greek "" meaning "darkening", "dark", or "obscure") is a painless temporary loss of vision in one or both eyes.

Other symptoms of the syndrome include:

- retroorbital pain due to pain in the area supplied by the ophthalmic branch of the trigeminal nerve (fifth cranial nerve),

- abducens nerve palsy (sixth cranial nerve), and

- otitis media.

Other symptoms can include photophobia, excessive lacrimation, fever, and reduced corneal sensitivity.

The syndrome is usually caused by the spread of an infection into the petrous apex of the temporal bone.

The headaches can vary greatly in their clinical presentation and duration.

Quality of the headache has been described as dull and/or pressure-like sensation, and throbbing and/or pulsating sensation. The pain is usually on both sides of the head (in 88–93% of people with NDPH), but may be unilateral, and may be localized to any head region. The pain can fluctuate in intensity and duration, is daily, and lasts more than 3 months.

There may be accompanying photophobia, phonophobia, lightheadedness or mild nausea. Co-morbidity with mood disorders has been reported in a subset of patients.

Cranial autonomic nervous symptoms occur with painful exacerbations in 21%, and cutaneous allodynia may be present in 26%.

In 2002, Li and Rozen conducted a study of 56 patients at the Jefferson Headache Center in Philadelphia and published the following results:

- 82% of patients were able to pinpoint the exact day their headache started.

- 30% of the patients, the onset of the headache occurred in correlation with an infection or flu-like illness.

- 38% of the patients had a prior personal history of headache.

- 29% of the patients had a family history of headache.

- 68% reported nausea.

- 66% reported photophobia.

- 61% reported phonophobia.

- 55% reported lightheadedness.

Imaging and laboratory testing were unremarkable except for an unusually high number of patients who tested positive for a past Epstein-Barr virus infection.