• embolic (clot; atheroemboli)
• giant-cell (temporal or cranial) arteritis (granulomatous)
• Takayasu arteritis (type I: aortic arch syndrome), types I-IV. (granulomatous)
• syphilitic aortitis
• tropical aortitis
• sarcoidosis
• Cojan's syndrome
• Wiskott-Aldrich syndrome
• non-luetic infectious aneurysms (salmonella, staph., enterococci).
• atherosclerotic aortic aneurysm
• inflammatory abdominal aortic aneurysm

• temporal arteritis (like this, there can be intracranial arteritis of similar type causing pain, TIA, stroke).
• polyarteritis nodosa (PAN)(negative for MCLN; negative lungs)
• embolic vasculitis
• Kawasaki disease (must have mucocutaneous lymph node syndrome [MCLN]): usual age 2 or less, unresponsive fever, bilateral nonsuppurative conjunctivitis, strawberry tongue, oropharyngeal injection/red, followed by red palms and soles, followed by desquamation...an acute vasculitis of unknown cause that occurs predominantly in infants and young children and produces coronary artery aneurysms in approximately 15% to 25% of those affected.
• Behcet's disease
• familial Medierranian fever
• cutaneous polyarteritis nodosa
• ANCA associated Wegener's granulomatosis, Churg-Strauss syndrome, microscpic polyangiitis
• overlap syndromes of PAN, Churg-Strauss, and hypersensitivity vasculitis.
• Buerger's disease (thromboangiitis obliterans): younger adults and almost exclusively cigarette smokers, affecting distal extremity arteries with thrombosis containing giant cells.
• primary angiitis of the CNS
• thromboangiitis obliterans
• MIVOD (mesenteric inflammatory veno-occlusive disease): 1st noted 1994; is a spectrum of venulitis to phlebitis which can be lymphocytic, necrotizing, granulomatous, or mixed & it has a thrombotic component; no arterial component and causes intestinal ischemia which can be surgical, even fatal; no medication or ANCA associations; one case with anti-phospholipid syndrome (APS).
• vasculitis of connective tissue disease
• isolated granulomatous phlebitis: arteries spared & colon perf. due to ischemic colitis [a variant of MIVOD?]
• idiopathic enterocolic lymphocytic phlebitis: stenosing cecal mass with colon ischemia [a variant of MIVOD?]
• lepromatous arteritis

1. Small-vessel vasculitis (DFA immuno-testing on biopsies can help) [check out a differential diagnosis table]
   • pauci-immune (few/no immune deposits) small-vessel vasculitis
     • Wegener's granulomatosis...Diff. Dx: granulomas and no asthma
     • microscopic polyangiitis (old terms, microscopic polyarteritis, microscopic periarteritis): an aggressive systemic necrotizing vasculitis with few or no immune deposits needing rapid diagnosis...key effects in kidneys (necrotizing and crescentic glomerulonephritis)  and lungs (hemorrhagic pulmonary capillaritis)...Diff. Dx: no asthma & no granulomas
     • Churg-Strauss (allergic angiitis and granulomatosis) Syndrome (CSS)...Diff. Dx group: asthmatics, granulomas and blood eosinophilia (ring granulomas around germinal centers, granulomas with central "eosinophilic abscesses"; eosinophilic vasculitis)
     • primary angiitis (granulomatous) of CNS (no skin lesions)
     • drug-induced ANCA-positive vasculitis
     • isolated retinal vasculitis
     • arteritis & venulitis secondary to other (such as intestinal-adhesional ischemic ulcerations causing some secondary granulomatous enteritis [vs. lumenal contents]) lesions: usually close (1-2 cm.) to the primary lesion and inflammatory character...even granulomatous...tends to reflect that of the primary lesion.
   • skin:
     • septic:
       1. clinical lesions: may be as red macules, petechiae, hemorrhagic vesicles & bullae, hemorrhagic crusts, and ulcers
       2. micro:
          • early lesions: superficial & deep perivascular & interstitial polys and lymphocytes
          • fully developed lesions: as with "early" but heavier; plus, thrombi; papillary dermal edema to vessiculation to necrosis.
          • late lesions: perivascular as with early except polys mostly interstitial; plus thrombi
     •   lymphocytic³:
       1. micro: often does not give much differential-diagnosis help except to bracket [LMC-03-409]
       2. diseases:
          • venular with typical lymphs:
            1. frost bite (chilblains/pernio)...50% of cases
            2. rickettsial lesions (epidermis can necrose)
            3. drug reactions
            4. allograft rejection
            5. idiopathic
            6. livedo vasculopathy
            7. Behcet's disease (?)
            8. collagen vascular disease (?)
            9. resolving leukocytoclastic vasculitis
            10. plus interface dermatitis:
            11. plus ballooning degeneration of keratinocytes:
            12. plus psoriasiform epidermal hyperplasia, spongiosis, or focal epidermal necrosis:
            13. plus extravascular necrosis:
            14. plus panniculitis:
          • venular with atypical lymphs:
            1. lymphomatoid papulosis
            2. mycosis fungoides (rarely)
            3. adult T-cell leukemia/lymphoma (rarely)
            4. disseminated pagetoid reticulosis (rarely)
            5. angiocentric lymphoma
            6. lymphomatoid drug eruptions (rarely)
          • arteriolar:
            1. Sneddon's syndrome
            2. Degos' disease
     • leukocytoclastic (immune-complex small-vessel) vasculitis...angiitis(leukocytoclastic [LCV] or hypersensitivity vasculitis; palpable purpura): lesions tend to be in dependent locations due to hydrostatic pressure effect on damaged vessels; post-capillary venulitis is much more common than capillaritis and arteriolitis.[S-01-8683]
       • Henoch-Schonlein purpura: IgA deposits dominate (usually children; palpable purpura, arthralgias, colicky GI symptoms, and glomerulonephritis)
       • acute generalized pustulosis: predilection for distal extremities; has leukocytoclastic vasculitis
       • cryoglobulinemic vasculitis: cryoproteins detectible in blood...may reflect hepatitis C, other infections, collagen vascular disease, arthralgia-purpura-weakness syndrome of Peetom-Melzer, and hematologic malignancies.
       • Bechet's disease: oral aphthous ulcers and skin vasculitis in absence of collagen vascular disease or IBD [S-01-4004?].
       • Goodpasture's syndrome (anti-GBM disease)
       • lupus vasculitis: ANA serological positivities (can develop a systemic vasculitis resembling CPN)
       • scleroderma: fibrinoid acute phase followed by obliterative sclerosis
       • dermatomyositis: vasculitis most common in childhood variant
       • mixed connective tissue disease (MCTD): similar to lupus, scleroderma, or MCTD.
       • rheumatoid vasculitis: usually in long-standing cases with high levels of RF (can vary from small vessel to arteritis)
       • serum sickness vasculitis
       • drug-induced immune-complex  serum-sickness-like vasculitis (old terminology, hypersensitivity vasculitis...which was usually in those over 20 years of age, and the acute phase of disease caused Ag-Ab complexes and reduced complement in serum...skin is usual site, with palpable purpura and leukocytoclastic-type of vasculitis acutely and lymphocytic type later). [S06-6687]
       • infection-induced immune-complex vasculitis (such as HIV or HCV) & HBV has produced cutaneous vasculitis, PAN, and cryoglobulinemic vasculitis also as secondary vasculitis.
       • urticaria, prolonged (>24 hour) lesions:
         • urticarial vasculitis (see peteciae, purpura, and/or siderotic hyperpigmentation in lesions):
           • hypocomplementemic (congenital or acquired) tend systemic sxs
           • normocomplementemic (congenital or acquired) urticarial vasculitis
       • late-phase (eosinophilic) urticaria⁵: non-LCV, non-fibrinonecrotic vasculitis (vasculocentric eos) in greater-than-24hour urticarial lesions.
       • late-phase (polys & eos) urticaria: non-LCV, non-fibrinonecrotic vasculitis (vasculocentric polys & eos) in greater-than-24-hour urticarial lesions.
       • erythema elevatum diutinum
       • myelodysplastic syndromes (MDS)
       • hyperimmunoglobulin D
       • paraneoplastic or neoplasm-associated vasculitis (especially lymphomas...lymphomatoid granulomatosis)
       • ulcerative-colitis-associated (IBD) vasculitis
       • Crohn's-disease-associated (IBD) vasculitis
       • biliary-cirrhosis-associated vasculitis
       • retroperitoneal-fibrosis-associated vasculitis
2. Vasculopathies:
   • arterial:
   • Heath-Edwards grading (for all [both primary and secondary pressure-induced change] hypertensive pulmonary vascular disease [HPVD] ) by H&E and elastic tissue stain⁴:
   1. Grade I: revert to double elastic layer of fetal pulmonary arterioles...reversible.
   2. Grade II: above plus addition of cellular intimal proliferation...reversible.
   3. Grade III: above plus addition of medial muscular thickening/hypertrophy...reversible [LMC-06-10582].
   4. Grade IV: above plus either fibrinoid mural change (may be preceeded by mural eos & polys) or angiomatoid or plexiform change...irreversible.
   • primary:
     1. primary pulmonary hypertension (PPH): Is diagnosed when secondary causes are ruled out; ll four grades of H-E change can be seen in PPH⁴.
     2. primary (idiopathic) arteriopathy of amyloidosis.
   • secondary:
     1. hypertensive pulmonary vascular disease (HPVD): a variety of pilmonary arterial pressure elevating diseases ...such as COPD & LV heart failure...cause grade I, II, & III changes, while grade IV change is rare in the absence of a left to right shunt⁴.
     2. diabetic arteriopathy.
     3. hypertensive arteriopathy.
     4. amyloidosis.
   • venous:
   • capillary:

REFERENCES:

1. 20th Edition Cecil Textbook of Medicine.
2. 4th Edition Dermatology in General Medicine.
3. Carlson, Mihm, and LeBoit text.
4. Personal communications with pulmonary and/or cardiovascular pathology experts (such as Jess Edwards trained JBC).
5. "late-phase urticaria" June 2007 update HERE.
6. Diseases A to Z vasculitis file HERE.

(posted 2000; latest additions 16 November 2008)