Vasculitis

Vasculitis is a group of disorders that destroy blood vessels by inflammation.[2] Both arteries and veins are affected. Lymphangitis (inflammation of lymphatic vessels) is sometimes considered a type of vasculitis.[3] Vasculitis is primarily caused by leukocyte migration and resultant damage. Although both occur in vasculitis, inflammation of veins (phlebitis) or arteries (arteritis) on their own are separate entities.

Vasculitis
Other namesVasculitides[1]
Petechia and purpura on the lower limb due to medication-induced vasculitis
Pronunciation
SpecialtyRheumatology, Immunology
SymptomsWeight loss, fever, myalgia, purpura
ComplicationsGangrene, Myocardial infarction

Signs and symptoms

Possible signs and symptoms include:[4][5]

Causes

There are several different etiologies for vasculitides. Although infections usually involve vessels as a component of more extensive tissue damage, they can also directly or indirectly cause vasculitic syndromes through immune-mediated secondary events. Simple vascular thrombosis usually only affects the luminal process, but through the process of thrombus organization, it can also occasionally cause a more chronic vasculitic syndrome. The autoimmune etiologies, a particular family of diseases characterized by dysregulated immune responses that produce particular pathophysiologic signs and symptoms, are more prevalent.[6]

Classification

Primary systemic, secondary, and single-organ vasculitis are distinguished using the highest classification level in the 2012 Chapel Hill Consensus Conference nomenclature.[7]

Primary systemic vasculitis

Primary systemic vasculitis is catogized by the size of the vessels mainly involved. Primary systemic vasculitis includes large-vessel vasculitis, medium-vessel vasculitis, small-vessel vasculitis, and variable-vessel vasculitis.[7]

Large vessel vasculitis

The 2012 Chapel Hill Consensus Conference defines large vessel vasculitis (LVV) as a type of vasculitis that can affect any size artery, but it usually affects the aorta and its major branches more frequently than other vasculitides.[7] Takayasu arteritis (TA) and giant cell arteritis (GCA) are the two main forms of LVV.[8]

Medium vessel vasculitis

Medium vessel vasculitis (MVV) is a type of vasculitis that mostly affects the medium arteries, which are the major arteries that supply the viscera and their branches. Any size artery could be impacted, though.[7] The two primary types are polyarteritis nodosa (PAN) and Kawasaki disease (KD).[8]

Small vessel vasculitis

Small vessel vasculitis (SVV) is separated into immune complex SVV and antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).[7]

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a necrotizing vasculitis linked to MPO-ANCA or PR3-ANCA that primarily affects small vessels and has few or no immune deposits. AAV is further classified as eosinophilic granulomatosis with polyangiitis (Churg-Strauss) (EGPA), granulomatosis with polyangiitis (Wegener's) (GPA), and microscopic polyangiitis (MPA).[7]

Immune complex small vessel vasculitis (SVV) is vasculitis that primarily affects small vessels and has moderate to significant immunoglobulin and complement component deposits on the vessel wall.[7] Normocomplementemic urticarial vasculitis (HUV) (anti-C1q vasculitis), cryoglobulinemic vasculitis (CV), IgA vasculitis (Henoch-Schönlein) (IgAV), and anti-glomerular basement membrane (anti-GBM) disease are the categories of immune complex SVV.[8]

Variable vessel vasculitis

Variable vessel vasculitis (VVV) is a kind of vasculitis that may impact vessels of all sizes (small, medium, and large) and any type (arteries, veins, and capillaries), with no particular type of vessel being predominantly affected.[7] This category includes Behcet's disease (BD) and Cogan's syndrome (CS).[8]

Secondary vasculitis

The subset of illnesses known as secondary vasculitis are those believed to be brought on by an underlying ailment or exposure. Systemic illnesses (such as rheumatoid arthritis), cancer, drug exposure, and infection are the primary causes of vasculitis; however, there are still few factors that have a conclusively shown pathogenic relationship to the condition.[9] Vasculitis frequently coexists with infections, and several infections, including hepatitis B and C, HIV, infective endocarditis, and tuberculosis, are significant secondary causes of vasculitis.[10] Except for rheumatoid vasculitis, the majority of secondary vasculitis forms are exceedingly rare.[11]

Single-organ vasculitis

Single-organ vasculitis, formerly known as "localized," "limited," "isolated," or "nonsystemic" vasculitis, refers to vasculitis that is limited to one organ or organ system. Examples of this type of vasculitis include gastrointestinal, cutaneous, and peripheral nerve vasculitis.[9]

Diagnosis

Micrograph showing a vasculitis (eosinophilic granulomatosis with polyangiitis). H&E stain.
Severe vasculitis of the major vessels, displayed on FDG-PET/CT
  • Some types of vasculitis display leukocytoclasis, which is vascular damage caused by nuclear debris from infiltrating neutrophils.[12] It typically presents as palpable purpura.[12] Conditions with leucocytoclasis mainly include hypersensitivity vasculitis (also called leukocytoclastic vasculitis) and cutaneous small-vessel vasculitis (also called cutaneous leukocytoclastic angiitis).
  • An alternative to biopsy can be an angiogram (x-ray test of the blood vessels). It can demonstrate characteristic patterns of inflammation in affected blood vessels.
  • 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT)has become a widely used imaging tool in patients with suspected Large Vessel Vasculitis, due to the enhanced glucose metabolism of inflamed vessel walls.[13] The combined evaluation of the intensity and the extension of FDG vessel uptake at diagnosis can predict the clinical course of the disease, separating patients with favourable or complicated progress.[14]
  • Acute onset of vasculitis-like symptoms in small children or babies may instead be the life-threatening purpura fulminans, usually associated with severe infection.
Laboratory Investigation of Vasculitic Syndromes[15]
DiseaseSerologic testAntigenAssociated laboratory features
Systemic lupus erythematosusANA including antibodies to dsDNA and ENA [including SM, Ro (SSA), La (SSB), and RNP]Nuclear antigensLeukopenia, thrombocytopenia, Coombs' test, complement activation: low serum concentrations of C3 and C4, positive immunofluorescence using Crithidia luciliae as substrate, antiphospholipid antibodies (i.e. anticardiolipin, lupus anticoagulant, false-positive VDRL)
Goodpasture's diseaseAnti-glomerular basement membrane antibodyEpitope on noncollagen domain of type IV collagen
Small vessel vasculitis
Microscopic polyangiitisPerinuclear antineutrophil cytoplasmic antibodyMyeloperoxidaseElevated CRP
Granulomatosis with polyangiitisCytoplasmic antineutrophil cytoplasmic antibodyProteinase 3 (PR3)Elevated CRP
Eosinophilic granulomatosis with polyangiitisperinuclear antineutrophil cytoplasmic antibody in some casesMyeloperoxidaseElevated CRP and eosinophilia
IgA vasculitis (Henoch-Schönlein purpura)None
CryoglobulinemiaCryoglobulins, rheumatoid factor, complement components, hepatitis C
Medium vessel vasculitis
Classical polyarteritis nodosaNoneElevated CRP and eosinophilia
Kawasaki's DiseaseNoneElevated CRP and ESR

In this table: ANA = antinuclear antibodies, CRP = C-reactive protein, ESR = erythrocyte sedimentation rate, dsDNA = double-stranded DNA, ENA = extractable nuclear antigens, RNP = ribonucleoproteins; VDRL = Venereal Disease Research Laboratory

Treatment

Treatments are generally directed toward stopping the inflammation and suppressing the immune system. Typically, corticosteroids such as prednisone are used. Additionally, other immune suppression medications, such as cyclophosphamide and others, are considered. In case of an infection, antimicrobial agents including cephalexin may be prescribed. Affected organs (such as the heart or lungs) may require specific medical treatment intended to improve their function during the active phase of the disease.[citation needed]

References

External links