Vasculitis is an inflammation of a broad spectrum of blood vessels ranging from aorta to capillaries and veins which can manifest itself with variable neurologic symptomatic as also neuropathologic changes in CNS and PNS.
| Classification of vasculitides | |
| Systemic necrotizing arteritis | Polyarteritis nodosaMicroscopic polyangiitis
Churg-Strauss syndrome |
| Hypersensitive vasculitis | Drug induced vasculitisHypocomplementemic vasculitis
Cryoglobulinemia |
| Systemic granulomatous vasculitis | Wegener’s granulomatosisLymphoid granulomatosis
Lethal midline granuloma |
| Giant-cell arteritis | Temporal arteritisTakayasu’s arteritis |
| CNS granulomatous angitis | - |
| Vasculitis associated collagen diseases | Systemic lupus erythematosusScleroderma
Rheumatoid arthritis Sjorgen’s syndrome Combined collagen disorder Behcet’s disease |
| Non-systemic vasculitic neuropathy | - |
| Infection associated vasculitis | Bacterial meningitisTuberculosis
Spiroheta (Treponema pallidum, Borrelia burgdorferi) Varicella zoster virus Fungal infections Human immunodeficiency virus |
| Amphetamine induced vasculitis | - |
| Paraneoplastic vasculitis | - |
| Inflammatory diabetic vasculopathy | |
Polyarteritis nodosa
Blood-vessel inflammation starts from invasion of intima media and adventitia of the vessel by polymorphonuclear cells, plasmatic cells, eozinophils and lymphocytes which results in an edema and fibrinoid necrosis of intima media. Vascular necrosis is followed by thrombosis of the vessel, distal ischemia, and formation of aneurismal sacs, ruptures and hemorrhages. Healing lesions exist simultaneously with fresh ones. In suspicious cases arteriography and biopsy of nerve and muscle is mandatory to make the diagnosis.
Microscopic polyangitis
This disease usually affects renal and lung vasculature (arterioles, capillaries and venules are affected) which results in necrotizing glomerulonephritis. Circulating antinuclear cytoplasmatic antibodies (ANCA) are detected in 80% cases, myeloperoxidase antibodies or p-ANCA are the most common. If epineural arteries are damaged polyneuropathy occurs in ¼ of patients.
Churg-Stross syndrome
This type of vasculitis may show granulomatouse or also non-granulomatous morphology, affects systemic and pulmonary arteries and veins. Necrotizing vasculitis and eosinophilic pneumonia-like lesions are characteristic for CS syndrome. There are 3 phases of the disease. First phase is like a prodromal period when patient is suffering from rhinitis and asthma. Blood and tissue eosinophilia is seen in second phase of the disease. At last vasculitis which manifests as peripheral neuropathies, ischemic and hemorrhagic cerebral strokes is seen in third phase of the disease. Laboratory diagnostics shows positive ANCA (MPO or p-ANCA) and biopsy of affected region is mandatory to make the diagnosis.
Hypersensitive vasculitis
This type of vasculitis begins with extravasation of erythrocytes, polymorphonuclear cell infiltration and monocitic, infiltration of vessel wall, which manifests as endothelial edema transforming into fibrinoid necrosis in affected arterioles, capillaries and postcapillarie veins. Circulating immune complexes are depositing in patient’s skin and affected inflamed vessel’s walls. The process may spread to other organs like peripheral nerves, kidneys, lungs, spleen, liver, heart and sometimes to CNS or guts where it can cause microinfarcts and microhemorrhages.
Drug induced vasculitis
Approximately, 20% of dermal vasculitides are drug induced. They are classified by type of allergic reaction: urtica, rhinitis, and laryngeal spasm, hypotensions which can last for minutes, hours or days. Usually, there is maculopappular rash or vesicles, rarely purpura of palpebra or extremity without systemic manifestation which reduces stopping the drug. Severe drug induced reactions can affect heart, spleen, liver, kidneys, lungs, gastrointestinal tract, CNS and PNS by focal deposition of immune complexes.
Cryoglobulinemia
Cryoglobulines are antibodies that reversibly precipitate at 37°C. They are made of IgG, IgM, compement, lipoproteins and antibody particle. Cryoglobilenes are classified into 3 types. First type made of monoclonal IgM or IgG. Second type is made of monoclonal IgM and polyclonal IgG. Third type is made of polyclonal antibodies and non-immunoglobulin molecules. First and second type cryoglobulinemias are associated with lymphoproliferative disorders (multiple myeloma, Wandenstrom’s macroglobulinemia). Cryoglobulins of first type can cause hyperviscosity syndrome. Third type cryoglobulines are associated with infectious disease and collagen vascular disorders.
The types of damage to vessel wall caused by cryoglobulinemia:
1) Occlusion of small and large blood-vessels caused by high concentration of cryoglobulins of first and second type;
2) Moderate thrombosis small arteries and arterioles;
3) Endothelial edema with thickening of the basal membrane;
4) Leukocytoclastic vasculitis.
First and second type cryglobulinemia are manifested by blood vessel’s occlusion with or without vasculitis in CNS. In contrast cryoglobulinemia of PNS manifests itself by epineural vasculitides, deposition of cryoprecipitates, and microvascular ischemia which manifests as axonopathy.
Cryoglobulinemia should be suspected in patients with characteristic skin changes, hyperviscosity syndrome, and increased clot formation. Hepatitis C is one of the risk factors. If cryoglobulinemia is found it is mandatory to perform bone marrow and nerve biopsies, as also test patient for HCV, HIV infections, and perform extensive research for oncology infection or collagen disorder.