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

Hypersensitivity vasculitis (allergic vasculitis). Usually due to a hypersensitivity reaction to a known drug. Drugs most commonly implicated are penicillin, sulphonamides and thiazide diuretics. There is presence of skin vaculitis with palpable petechiae or purpura. Biopsy of these lesions reveal inflammation of the small vessels, termed leukocytoclastic vasculitis, which is most prominent in postcapillary venules. At least 3 out of 5 criteria yields sensitivity and specificity of 71 and 84%:

- age > 16

- use of possible triggering drug in relation to symptoms

- palpable purpura

- maculopapular rash

- skin biopsy showing neutrophils around vessel

IgA vasculitis (IgAV; formerly known as Henoch-Schonlein purpura). Systemic vasculitis due to tissue deposition of IgA-containing immune complexes. Biopsy of lesions shows inflammation of small vessels. It is considered a form of hypersensitivity vasculitis but is distinguished by prominent deposits of IgA. This is the most common vasculitis in children. Presence of 3 or more criteria yielded sensitivity of 87% while less than 2 criteria yielded hypersensitivity vasculitis in 74%:

- palpable purpura (usually of buttocks & legs)

- bowel angina

- GI bleed

- hematuria

- onset < 20 years

- no new medications

Essential cryoglobulinemic vasculitis. Most often due to hepatitis C infection, immune complexes of cryoglobulins --- proteins that consists of immunoglobulins and complement and precipitate in the cold while dissolving upon rewarming --- are deposited in walls of capillaries, venules, or arterioles. Therefore, complement will be low with histology showing vessel inflammation with immune deposits.

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.

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

The second stage is characterized by an abnormally high level of eosinophils (a type of white blood cell) in the blood and tissues. The symptoms of hypereosinophilia depend on which part of the body is affected, but most often it affects the lungs and digestive tract. The signs and symptoms of hypereosinophilia may include weight loss, night sweats, asthma, cough, abdominal pain, and gastrointestinal bleeding. Fever and malaise are often present.

The eosinophilic stage can last months or years, and its symptoms can disappear, only to return later. Patients may experience the third stage simultaneously.

Initially red to pink, flat spots (formally, "macules") and raised bumps (formally, "papules") may be seen on the skin.

Once fully developed, the classic appearance is "non-blanching, palpable purpura". This appears as deep red to purple spots that feel raised to the touch. Purpura refers to the red-purple discolored spots, while palpable implies that these spots can be felt as raised from the surrounding skin. Additionally, when gently pressed, the color does not fade to a lighter color ("non-blanching"). The red-purple color of the lesions is due to the inflammation in the blood vessels causing red blood cells to escape into the dermis skin layer.

Small fluid-filled blisters (or "vesicles"), pus-filled bumps resembling a pimple (or "pustules"), or shallow ulcers may also develop but are less common.

The location of skin lesions varies but are most commonly found symmetrically below the waist, primarily on the buttocks and legs. Other distributions include localized areas on the upper body or over several areas of the body.

With treatment, the lesions typically resolve in weeks to months and leave behind flat spots that are darker than the surrounding skin. (see "Postinflammatory hyperpigmentation" on "Hyperpigmentation")

A portion of cases may be persistent or recurrent. This tends to occur when the vasculitis is associated with chronic conditions such as connective tissue diseases.

In most cases skin lesions do not cause symptoms, however itching, burning, or pain may occur.

Frequently reported symptoms include mild fever, muscle pain, joint pain, or an overall feeling of discomfort. Additional symptoms depend on the cause of the vasculitis and if other organ systems are involved. For example, if the vasculitis is a manifestation of Henoch-Schönlein purpura, individuals may also experience abdominal pain or blood in the urine.

Initial signs are extremely variable, and diagnosis can be severely delayed due to the nonspecific nature of the symptoms. In general, rhinitis is the first sign in most people.

- Kidney: rapidly progressive glomerulonephritis (75%), leading to chronic kidney failure

- Upper airway, eye and ear disease:

- Nose: pain, stuffiness, nosebleeds, rhinitis, crusting, "saddle-nose" deformity due to a perforated septum

- Ears: conductive hearing loss due to auditory tube dysfunction, sensorineural hearing loss (unclear mechanism)

- Oral cavity: strawberry gingivitis, underlying bone destruction with loosening of teeth, non-specific ulcerations throughout oral mucosa

- Eyes: pseudotumours, scleritis, conjunctivitis, uveitis, episcleritis

- Trachea: subglottal stenosis

- Lungs: pulmonary nodules (referred to as "coin lesions"), infiltrates (often interpreted as pneumonia), cavitary lesions, pulmonary haemorrhage causing haemoptysis, and rarely bronchial stenosis.

- Arthritis: Pain or swelling (60%), often initially diagnosed as rheumatoid arthritis

- Skin: nodules on the elbow, purpura, various others (see "cutaneous vasculitis")

- Nervous system: occasionally sensory neuropathy (10%) and rarely mononeuritis multiplex

- Heart, gastrointestinal tract, brain, other organs: rarely affected.

The prodromal stage is characterized by allergy. Almost all patients experience asthma and/or allergic rhinitis, with more than 90% having a history of asthma that is either a new development, or the worsening of pre-existing asthma, which may require systemic corticosteroid treatment. On average, asthma develops from three to nine years before the other signs and symptoms.

The allergic rhinitis may produce symptoms such as rhinorrhea and nasal obstruction, and the formation of nasal polyps that require surgical removal, often more than once. Sinusitis may also be present.

In this disease, symptoms result from ischemic damage to affected organs, often the skin, heart, kidneys, and nervous system. Generalised symptoms include fever, fatigue, weakness, loss of appetite, and weight loss. Muscle and joint aches are common. The skin may show rashes, swelling, ulcers, and lumps. Palpable purpura and livedo reticularis can occur in some patients.

Nerve involvement may cause sensory changes with numbness, pain, burning, and weakness (peripheral neuropathy). Central nervous system involvement may cause strokes or seizures. Kidney involvement can produce varying degrees of kidney failure, such as hypertension, edema, oliguria, and uremia. Involvement of the arteries of the heart may cause a heart attack, heart failure, and inflammation of the sac around the heart (pericarditis).

Polyarteritis nodosa, also known as panarteritis nodosa, periarteritis nodosa, Kussmaul disease, Kussmaul-Maier disease or PAN, is a systemic vasculitis of small- or medium-sized muscular arteries, typically involving renal and visceral vessels but sparing the pulmonary circulation. Polyarteritis nodosa may present in infants. In polyarteritis nodosa, small aneurysms are strung like the beads of a rosary, therefore making "rosary sign" an important diagnostic feature of the vasculitis.

With treatment, five-year survival is 80%; without treatment, five-year survival is 13%. Death is often a consequence of kidney failure, myocardial infarction, or stroke.

Clinical features may include constitutional symptoms like fever, loss of appetite, weight loss, fatigue, and kidney failure. A majority of patients may have blood in the urine and protein in the urine. Rapidly progressive glomerulonephritis may occur. Because many different organ systems may be involved, a wide range of symptoms are possible in MPA.

Purpura and livedo racemosa may be present.

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.

Microscopic polyangiitis is an ill-defined autoimmune disease characterized by a systemic, pauci-immune, necrotizing, small-vessel vasculitis without clinical or pathological evidence of necrotizing granulomatous inflammation.

Ophthalmic examination may reveal neovascularization (creation of new vessels in the retina), retinal vessel narrowing, retinal vessel cuffing, retinal hemorrhage, or possible vitritis (inflammation of the vitreous body) or choroiditis (inflammation of the choroid).

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis (WG), is a systemic disorder that involves both granulomatosis and . It is a form of vasculitis (inflammation of blood vessels) that affects small- and medium-size vessels in many organs. Damage to the lungs and kidneys can be fatal. Treatment requires long-term immunosuppression.

Granulomatosis with polyangiitis is part of a larger group of vasculitic syndromes called systemic vasculitides or necrotizing vasculopathies, all of which feature an autoimmune attack by an abnormal type of circulating antibody termed ANCAs (antineutrophil cytoplasmic antibodies) against small and medium-size blood vessels. Apart from GPA, this category includes eosinophilic granulomatosis with polyangiitis (EGPA) and microscopic polyangiitis. Although GPA affects small- and medium-size vessels, it is formally classified as one of the small vessel vasculitides in the Chapel Hill system.

Symptoms of general arteritis may include:

- Inflammation

- Fever

- Increased production of red blood cells (erythrocytes)

- Limping

- Reduced pulse

A rare autoimmune disease characterized by recurrent urticaria (nettle rash), first described in the 1970s. There is no defined paradigm for the syndrome aetiology and severity in progression. Diagnosis is confirmed with the identification of at least two conditions from: venulitis on skin biopsy, arthritis, ocular inflammation, abdominal pain or positive C1q antibodies to immune complexes. It is this last category, anti-C1q antibodies, that all HUV patients test positive for. "In vitro" experiments and mouse models of the disease have not thoroughly determined the link between these antibodies and the disease, even though the link is so pronounced.

Two or more of the following four criteria are required:

- Necrotizing ulcerating inflammation of nose, sinuses, mouth or pharynx

- Irregular lung infiltrates

- Nephritis

- Granulomatous vascular and perivascular inflammation

Three or more of the following six criteria must be met:

- Age when disease starts is under 50

- Decreased brachial artery pulse

- Systolic blood pressure differs by more than 10mmHg between arms

- Cramping caused by exercise in the extremities

- Abnormal sounds (through stethoscope) over subclavian arteries or abdominal aorta

- A narrowing or blockage in the aorta, its primary branches, or large arteries as seen through a radiograph of the arteries.

Urticarial vasculitis (also known as "chronic urticaria as a manifestation of venulitis", "hypocomplementemic urticarial vasculitis syndrome", "hypocomplementemic vasculitis" and "unusual lupus-like syndrome") is a skin condition characterized by fixed urticarial lesions that appear histologically as a vasculitis.

Kawasaki disease often begins with a high and persistent fever that is not very responsive to normal treatment with paracetamol (acetaminophen) or ibuprofen. It is the most prominent symptom in Kawasaki disease, is a characteristic sign of the acute phase of the disease, is normally high (above 39–40 °C), is remittent, and is followed by extreme irritability. Recently, it is reported to be present in patients with atypical or incomplete Kawasaki disease; nevertheless, it is not present in 100% of cases. The first day of fever is considered the first day of illness, and the duration of fever is on average one to two weeks; in the absence of treatment, it may extend for three to four weeks. Prolonged fever is associated with higher incidence of cardiac involvement. It responds partially to antipyretic drugs and does not cease with the introduction of antibiotics. However, when appropriate therapy is started – intravenous immunoglobulin and aspirin – the fever is gone after two days.

Bilateral conjunctival inflammation was reported to be the most common symptom after fever. It typically involves the bulbar conjunctivae, is not accompanied by suppuration, and is not painful. It usually begins shortly after the onset of fever during the acute stage of the disease. Anterior uveitis may be present on slit-lamp examination. Iritis can occur, too. Keratic precipitates are another eye manifestation (detectable by a slit lamp but are usually too small to be seen by the unaided eye).

Kawasaki disease presents with set of mouth symptoms, the most characteristic changes are the red tongue, swollen lips with vertical cracking and bleeding. The mucosa of the mouth and throat may be bright red, and the tongue may have a typical "strawberry tongue" appearance (marked redness with prominent gustative papillae). These mouth symptoms are caused by the typical necrotizing microvasculitis with fibrinoid necrosis.

Cervical lymphadenopathy is seen in 50% to 75% of people, whereas the other features are estimated to occur in 90% of patients, but sometimes it can be the dominant presenting symptom. According to the definition of the diagnostic criteria, at least one impaired lymph node ≥ 15 mm in diameter should be involved. Affected lymph nodes are painless or minimally painful, nonfluctuant, and nonsuppurative; erythema of the neighboring skin may occur. Children with fever and neck adenitis who do not respond to antibiotics should have Kawasaki disease considered as part of the differential diagnoses.

In the acute phase of the disease, changes in the peripheral extremities can include erythema of the palms and soles, which is often striking with sharp demarcation and often accompanied by painful, brawny edema of the dorsa of the hands or feet. This is why affected children frequently refuse to hold objects in their hands or to bear weight on their feet. Later, during the convalescent or the subacute phase, desquamation of the fingers and toes usually begins in the periungual region within two to three weeks after the onset of fever and may extend to include the palms and soles. Around 11% of children affected by the disease may continue skin-peeling for many years. One to two months after the onset of fever, deep transverse grooves across the nails may develop (Beau’s lines), and occasionally nails are shed.

The most common skin manifestation is a diffuse macular-papular erythematous rash, which is quite nonspecific. The rash varies over time and is characteristically located on the trunk; it may further spread to involve the face, extremities, and perineum. Many other forms of cutaneous lesions have been reported; they may include scarlatiniform, papular, urticariform, multiform-like erythema, and purpuric lesions; even micropustules were reported. It can be polymorphic, not itchy, and normally observed up to the fifth day of fever. However, it is never bullous or vesicular.

In the acute stage of Kawasaki disease, systemic inflammatory changes are evident in many organs. Joint pain (arthralgia) and swelling, frequently symmetrical, and arthritis can also occur. Myocarditis, diarrhea, pericarditis, valvulitis, aseptic meningitis, pneumonitis, lymphadenitis, and hepatitis may be present and are manifested by the presence of inflammatory cells in the affected tissues. If left untreated, some symptoms will eventually relent, but coronary artery aneurysms will not improve, resulting in a significant risk of death or disability due to myocardial infarction. If treated quickly, this risk can be mostly avoided and the course of illness cut short.

Other reported nonspecific symptoms include cough, rhinorrhea, sputum, vomiting, headache, and seizure.

The course of the disease can be divided into three clinical phases.

- The acute febrile phase, which usually lasts for one to two weeks, is characterized by fever, conjunctival injection, erythema of the oral mucosa, erythema and swelling of the hands and feet, rash, cervical adenopathy, aseptic meningitis, diarrhea, and hepatic dysfunction. Myocarditis is common during this time, and a pericardial effusion may be present. Coronary arteritis may be present, but aneurysms are generally not yet visible by echocardiography.

- The subacute phase begins when fever, rash, and lymphadenopathy resolve at about one to two weeks after the onset of fever, but irritability, anorexia, and conjunctival injection persist. Desquamation of the fingers and toes and thrombocytosis are seen during this stage, which generally lasts until about four weeks after the onset of fever. Coronary artery aneurysms usually develop during this time, and the risk for sudden death is highest.

- The convalescent stage begins when all clinical signs of illness have disappeared, and continues until the sedimentation rate returns to normal, usually at six to eight weeks after the onset of illness.

The presentation between adults and children differs, as adults' neck lymph nodes are more affected (93% of adults versus 15% of children), hepatitis (65% versus 10%), and arthralgia (61% versus 24–38%). Some people have atypical presentations and may not have the classical symptoms. This occurs in particular in young infants; those people are especially at higher risk for cardiac artery aneurysms.

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.

Lung involvement is typically in the form of hemoptysis, pleuritis, cough, or fever, and in severe cases can be life-threatening if the outlet pulmonary artery develops an aneurysm which ruptures causing severe vascular collapse and death from bleeding in the lungs. Nodules, consolidations, cavities and ground glass lesions are common in patients with pulmonary involvement. Pulmonary artery thrombosis may occur.

Erythema induratum, or "Bazin disease", is a panniculitis on the back of the calves. It was formerly thought to be a reaction to the tuberculum bacillus. It is now considered a panniculitis that is not associated with a single defined pathogen.

Nodular vasculitis is a skin condition characterized by small, tender, reddened nodules on the legs, mostly on the calves and shins. Microscopically there are epithelioid granulomas and vasculitis in the subcutaneous tissue, making it a form of panicullitis. Most of these cases are now thought to be manifestation of tuberculosis and indeed they respond well to anti-tuberculous treatment.