Polyangiitis overlap syndrome. Classification and prospective clinical experience

Absence of ANCA in Mexican patients with Takayasu's arteritis

Antineutrophil cytoplasmic autoantibodies (ANCA) were sought in 43 sera from 39 Mexican patients with typical Takayasu's arteritis (TA), (5 with active and 34 with inactive disease), and in a comparative group comprising 50 sera. Results were negative in all cases. This suggests that ANCA are not a serologic feature in TA per se, even during its active stage. ANCA positivity in TA, when present, may be a non-related phenomenon and probably identifies a subset of patients with atypical forms of TA or a polyangiitis overlap syndrome.

[Pleuropulmonary manifestations of systemic vasculitis]

Pleuropulmonary manifestations of systemic vasculitis are common, polymorphic and of ambiguous significance: the same pulmonary lesion may reveal a specific manifestation of vasculitis as well as a therapy-induced complication, especially infection which may favor per se a flare-up. Two questions will be successively studied: what are the pleuropulmonary characteristics of Wegener's granulomatosis, Churg-Strauss syndrome, periarteritis nodosa, Behçet's disease, Takayasu's disease and temporal arteritis? What are the major adverse effects that may occur in the course of a treated systemic vasculitis?

Wegener's granulomatosis overlapped with Takayasu arteritis

A 27-year-old woman presented with destructive scleritis of the left eye with subcutaneous haemorrhage and swelling of the lower eyelid. She had experienced recurrent nasal bleeding for the last six years, and chronic sinusitis resulting in the destruction of the nasal septum and left maxillary sinus. Nasal mucosal biopsies demonstrated granuloma formation with no evidence of vasculitis. The level of serum cytoplasmic anti-neutrophil cytoplasm antibody (c-ANCA) was significantly increased. Furthermore, multiple sites of complete occlusions were detected in the left subclavian and common carotid arteries by subtraction angiography and MRI. We describe a case of Wegener's granulomatosis overlapped with Takayasu arteritis, which, to our knowledge, has not been previously reported.

IgA multiple myeloma presenting as Henoch-Schönlein purpura/polyarteritis nodosa overlap syndrome

We report the unusual case of a man with a 5-year history of relapsing Henoch-Schonlein purpura (HSP) and macroscopic polyarteritis nodosa (PAN) as early manifestations of IgA kappa multiple myeloma. The glomeruli contained monoclonal IgA kappa deposits, without other immunoglobulins or lambda light chains. Glomerular deposits lacked the usual electron density but could be demonstrated by immunoelectron microscopy. Multisystem large vessel vasculitis (antineutrophil cytoplasmic antibody negative) produced aneurysms of renal and hepatic arteries, whereas small vessel vasculitis affected the skin and glomeruli, producing a symptom complex of HSP with dermal and glomerular deposits of IgA. We conclude that HSP/overlap syndrome may be the initial manifestation of IgA myeloma and should be considered within the spectrum of monoclonal IgA deposition disease.

Six cases of microscopic polyarteritis exhibiting acute interstitial pneumonia

Out of 21 autopsy cases of microscopic polyarteritis (MPA), six cases that died of acute respiratory failure are described. All of these six cases exhibited pauci-immune necrotizing glomerulonephritis. Of these six cases, systemic vasculitis and respiratory failure occurred almost simultaneously in two, whereas respiratory failure developed when vasculitis recurred in the other four. Pathologically, pulmonary changes were diffuse and almost uniform in each case. Interstitial inflammatory cells (alveolitis), hyaline membrane, restructuring, and fibrosis were observed. The degrees of these changes differed from case to case; four cases showed predominantly exudative changes and two cases exhibited proliferative or organizing ones. Clinical and pathological features were consistent with acute interstitial pneumonia (AIP). Immunofluorescent and ultrastructural studies did not suggest deposition of immune complexes at the lesions of alveolitis. An etiologic agent could not be identified in these cases. Some lung lesions including pulmonary hemorrhage have been described in association with MPA; however, cases such as those presented here have rarely been reported. It was considered that AIP could be one of the pulmonary disorders in MPA. Furthermore, the possible pathogenetic role of antineutrophil cytoplasmic antibodies (ANCA) in the evolution of present lung lesion is discussed. Although ANCA were not examined in the present cases, these antibodies should be investigated in future cases.

Southwestern Internal Medicine Conference: vasculitis--it's time to reclassify

Based on the lack of knowledge of pathophysiologic mechanisms, there has not been a clear and consistent classification of vasculitides. During the past few years, our understanding of these disorders has been enhanced by an appreciation of the role of anti-neutrophil cytoplasmic antibodies. These antibodies exist in two types, a c-ANCA, which corresponds to anti-proteinase 3 antibodies, and a p-ANCA, which corresponds mostly with anti-myeloperoxidase antibodies. Treatment has improved prognosis markedly in these diseases. Most patients can be successfully treated with combinations of treatments including steroids, pulse steroids, cytotoxic agents, and plasmapheresis. Based on antineutrophil cytoplasmic antibodies and response to treatment, a classification is proposed. This classification includes all necrotizing crescentic glomerulonephritis as vasculitis. The vasculitides are divided according to whether they involve large arteries, medium arteries, or small vessels, which include arterioles, capillaries, and venules. Small vessel vasculitides frequently are associated with necrotizing crescentic glomerulonephritis and are divided into three categories: ANCA-associated, anti-GBM associated, and immune complex-associated. Renal biopsy is extremely useful in providing pathologic confirmation of small vessel vasculitis.

Angiotropic large cell lymphoma with mononeuritis multiplex mimicking systemic vasculitis

Angiotropic large cell lymphoma (ALCL), the so-called malignant angioendotheliomatosis, is characterised by proliferation of tumorous cells within small vessels. Manifestations in the CNS and cutaneous lesions prevail in the clinical presentation, although any organ can be involved. The recent classification of this lymphoma as part of the large cell lymphomas has modified the therapeutic approaches employed. This should improve the prognosis of this usually fatal disease. An unusual case presenting with fever, mononeuritis multiplex, and cutaneous lesions is reported. Peripheral neuropathy without other neurological symptoms is uncommon, and, to our knowledge, such isolated mononeuritis multiplex with nerve lesions has not been previously reported in ALCL. The clinical diagnosis was a systemic necrotising vasculitis and it is considered that its differential diagnosis must include angiotropic large cell lymphoma.

Pulmonary hemorrhage in children with glomerulonephritis

Pulmonary hemorrhage may occur in patients with immune-mediated glomerulonephritis. This association can be seen in a variety of disorders including systemic lupus erythematosus, vasculitis, Wegener's granulomatosis, anaphylactoid purpura and Goodpasture's syndrome. Immune mechanisms, such as immune complexes and/or autoantibodies, play a role in the pathogenesis of pulmonary and glomerular injury. Acute pulmonary hemorrhage can lead to respiratory failure and has a high mortality. Therapy with immunosuppressive agents such as pulse methylprednisolone and cyclophosphamide will control the hemorrhage and improve pulmonary function in most cases.

Outcome of polyarteritis nodosa and Churg-Strauss syndrome. An analysis of twenty-five patients

OBJECTIVE

To compare outcome in patients with polyarteritis nodosa (PAN) and patients with Churg-Strauss syndrome (CSS) followed up at a single center.

METHODS

A retrospective data review of 13 patients with PAN and 12 patients with CSS who were followed up at a vasculitis clinic. Outcome measures included a global damage index, disability and pain dimensions of the Health Assessment Questionnaire, and mortality rate.

RESULTS

Compared with patients with CSS, patients with PAN had a significantly higher mean damage index score (5.15 versus 2.42; P = 0.011), a higher disability score (1.09 versus 0.16; P = 0.007), and a higher pain score (1.04 versus 0.01; P = 0.017). Patients with PAN had more relapses (relative risk = 5.07; P < 0.000) and a higher mortality rate (31%) compared with patients with CSS (8%).

CONCLUSION

PAN and CSS differ in their morbidity and mortality; therefore, they should be considered as distinct clinical entities.

The arteritides

This article reviews the histopathological, clinical and immunological features of the arteritides. Based on these criteria, a classification scheme is proposed that includes infectious and non-infectious causes. Included in the non-infectious arteritides are: hypersensitivity vasculitis including serum sickness. Henoch-Schönlein purpura, mixed cryoglobulinaemia, hypocomplementaemia, drug and malignancy-associated vasculitis; arteritides of small and medium-sized arteries including polyarteritis nodosa, Kawasaki's disease, Wegener's granulomatosis, Churg-Strauss syndrome, necrotizing sarcoid granulomatosis, thromboangiitis obliterans (Buerger's disease) and localized forms of arteritis; arteritides involving large, medium and small-sized arteries which includes giant cell (temporal) arteritis, Takayasu's disease and arteritis of collagen-vascular disease (rheumatoid arthritis, rheumatic fever, Behçet's disease, Sjörgren's syndrome, systemic lupus erythematosis and systemic sclerosis.

Anti-neutrophil cytoplasmic antibodies (ANCA): their detection and significance: report from workshops

Anti-neutrophil cytoplasmic antibodies (ANCA) are antibodies directed against enzymes that are found mainly within the azurophil or primary granules of neutrophils. There are 3 types of ANCA that can be distinguished by the patterns they produce by indirect immunofluorescence when tested on normal ethanol-fixed neutrophils. Diffuse fine granular cytoplasmic fluorescence (cANCA) is typically found in Wegener's granulomatosis, in some cases of microscopic polyarteritis and Churg Strauss syndrome, and in some cases of crescentic and segmental necrotising glomerulonephritis, but it is rare in other conditions. The target antigen is usually proteinase 3. Perinuclear fluorescence (pANCA) is found in many cases of microscopic polyarteritis and in other cases of crescentic and segmental necrotising glomerulonephritis. These antibodies are often directed against myeloperoxidase but other targets include elastase, cathepsin G, lactoferrin, lysozyme and beta-glucuronidase. The third group designated "atypical" ANCA includes neutrophil nuclear fluorescence and some unusual cytoplasmic patterns, and while a few of the target antigens are shared with pANCA, the others have not been identified. Sera that produce a pANCA or atypical ANCA pattern on alcohol-fixed neutrophils result in cytoplasmic fluorescence when formalin acetone fixation is used. pANCA or atypical ANCA occur in about 2/3 of all individuals with ulcerative colitis or primary sclerosing cholangitis, and they are found in a third of patients with Crohn's disease. The reported incidence of ANCA in rheumatoid arthritis and SLE varies considerably but the patterns are predominantly pANCA and atypical ANCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Takayasu arteritis with acute interstitial pneumonia and coronary vasculitis: expanding the spectrum. Report of a case

We describe the first reported case of Takayasu arteritis presenting as idiopathic adult respiratory distress syndrome, with a pathologic diagnosis of acute interstitial pneumonia. In the same patient, rarely occurring, diffuse coronary vasculitis developed. This case vividly illustrates the extensive, clinically significant vascular involvement that can occur in Takayasu arteritis, as well as the potential extravascular, multisystemic nature of the disease.

Pulmonary capillaritis. The association with progressive irreversible airflow limitation and hyperinflation

We report two patients with systemic necrotizing vasculitis (microscopic polyarteritis) and associated recurrent pulmonary capillaritis, in whom progressive irreversible airway dysfunction began approximately 10 yr after disease onset. Their course was characterized by repeated episodes of diffuse alveolar hemorrhage, glomerulonephritis, palpable purpura, and splinter hemorrhages. The lung revealed intraalveolar hemorrhage, neutrophilic infiltration and cellular fragmentation, fibrinoid necrosis of the alveolar interstitium, and parenchymal hemosiderin deposits. No medium-sized vessel involvement, granulomatous inflammation, or bronchiolar obliteration were seen. Renal biopsies revealed focal segmental necrotizing glomerulonephritis, and a cutaneous biopsy in one case showed a leukocytoclastic vasculitis. Immunofluorescent studies of lung and kidney showed minimal or no immunoreactivity. The clinical course and serologic tests did not support another systemic vasculitis, connective tissue disease, or antiglomerular basement membrane antibody disease. The acute episodes responded to antiinflammatory and immunosuppressive therapy. Symptoms, serial pulmonary function tests, and chest imaging documented the development of a progressive irreversible obstructive airway disease. No other predisposing factors were identified. These cases demonstrate the unexpected appearance of an irreversible obstructive airway disease with lung parenchymal hyperinflation after systemic necrotizing vasculitis associated with recurrent pulmonary capillaritis and diffuse alveolar hemorrhage.

Antineutrophil cytoplasmic antibodies: a still-growing class of autoantibodies in inflammatory disorders

Antineutrophil cytoplasmic antibodies (ANCA) have been described as sensitive and specific markers for active Wegener's granulomatosis (WG). ANCA in WG produce a characteristic cytoplasmic staining pattern of neutrophils (c-ANCA) and are directed against proteinase 3 (Pr3), a serine protease from the azurophilic granules. c-ANCA, more or less equivalent to anti-Pr3, occur in more than 90% of patients with extended WG, in 75% of patients with limited WG without renal involvement, and in some 40% to 50% of patients with vasculitic overlap syndromes suggestive of WG such as microscopic polyarteritis. The presence of c-ANCA is highly specific for those diseases (greater than 98%). Changes of levels of c-ANCA precede disease activity and may be used as guidelines for treatment. Antibodies producing a perinuclear staining of ethanol-fixed neutrophils (p-ANCA) occur in a wide range of diseases. They are directed against different cytoplasmic constituents of neutrophils. Among those, antibodies to myeloperoxidase are found in patients with idiopathic crescentic glomerulonephritis, the Churg-Strauss syndrome, polyarteritis nodosa with visceral involvement, and vasculitic overlap syndromes. Their specificity for this group of necrotizing vasculitides is high (94% to 99%), although they may occur in patients with hydralazine-induced glomerulonephritis, anti-glomerular basement membrane disease, and possibly in some patients with idiopathic systemic lupus erythematosus. Antibodies to leukocyte elastase are incidentally found in patients with vasculitic disorders, whereas lactoferrin antibodies are detected in patients with primary sclerosing cholangitis with or without ulcerative colitis and in rheumatoid arthritis. Their diagnostic significance awaits further studies. p-ANCA of undefined specificity may distinguish ulcerative colitis (sensitivity of 75%) from Crohn's disease (sensitivity of 20%). p-ANCA also occur in autoimmune liver diseases: in 75% of patients with chronic active hepatitis, in 60% to 85% of those with primary sclerosing cholangitis, and in about 30% of patients with primary biliary cirrhosis. Finally, p-ANCA are detected in chronic arthritides and in some 5% of healthy controls. Assessment of their diagnostic value has to await further characterization of the antigens involved, allowing the development of antigen-specific assays.

Nomenclature of vasculitic syndromes: a historical perspective

Since the original description of periarteritis nodosa (PAN) in 1866, the number of recognized forms of so-called idiopathic vasculitis has risen to about a dozen. Their relation to each other and their nature remain unclear, although the recent discovery of antineutrophil cytoplasmic autoantibodies (ANCA) promises a clue to the origin of at least some of them, particularly Wegener's granulomatosis (WG) and perhaps also Churg-Strauss syndrome (CSS). On the other hand, PAN appears to be a nonspecific syndrome of various etiologies.

Cutaneous polyarteritis nodosa and Crohn's disease

We report a case of a 57-year-old woman who presented simultaneously cutaneous polyarteritis nodosa and Crohn's disease of the colon. Although similar pathogenic hypotheses have been reported, the association of both diseases is exceptional.

Association of autoantibodies to myeloperoxidase with different forms of vasculitis

Antineutrophil cytoplasmic autoantibodies with specificity for myeloperoxidase (MPO) were found in 53 patient sera that were routinely submitted for antineutrophil cytoplasmic antibody determination. Based on clinical and histologic criteria, 15 of these 53 patients were classified as having systemic necrotizing vasculitis of the polyarteritis group, 11 patients were classified as having Wegener's granulomatosis (WG), and 14 were classified as having idiopathic crescentic glomerulonephritis. The remaining 13 patients did not fulfill the diagnostic criteria for these disorders, although most of these patients had clinical symptoms compatible with these disorders. While all patients with WG had renal involvement, only 4 of the 15 patients with systemic necrotizing vasculitis of the polyarteritis group had glomerulonephritis. The sensitivity of autoantibodies to MPO for either systemic necrotizing vasculitis of the polyarteritis group, WG, or idiopathic crescentic glomerulonephritis was further tested in all our patients with these disorders (n = 104). Twenty-seven of 104 patients had autoantibodies to MPO. Furthermore, 69 of the remaining 77 patients had autoantibodies specific for the 29-kd serine protease, which has been reported to be specifically associated with WG. Sera from 8 patients were negative for either of these antibodies (92% sensitivity of autoantibodies to MPO and/or the 29-kd serine protease). The specificity of autoantibodies to MPO for either systemic necrotizing vasculitis of the polyarteritis group, WG, or idiopathic crescentic glomerulonephritis was also tested in selected groups of patients who had closely related diseases. Two of 144 patients had autoantibodies to MPO (specificity 99%).(ABSTRACT TRUNCATED AT 250 WORDS)

The American College of Rheumatology 1990 criteria for the classification of polyarteritis nodosa

Criteria for the classification of polyarteritis nodosa were developed by comparing 118 patients who had this disease with 689 control patients who had other forms of vasculitis. For the traditional format classification, 10 criteria were selected: weight loss greater than or equal to 4 kg, livedo reticularis, testicular pain or tenderness, myalgias, mononeuropathy or polyneuropathy, diastolic blood pressure greater than 90 mm Hg, elevated blood urea nitrogen or serum creatinine levels, presence of hepatitis B reactants in serum, arteriographic abnormality, and presence of granulocyte or mixed leukocyte infiltrate in an arterial wall on biopsy. The presence of 3 or more of these 10 criteria was associated with a sensitivity of 82.2% and specificity of 86.6%. A classification tree was also constructed, with 6 criteria being selected. Three of these, angiographic abnormality, biopsy-proven granulocyte or mixed leukocyte infiltrate in arterial wall, and neuropathy, were criteria used in the traditional format. The other 3 criteria used in the tree format included the patient's sex, weight loss greater than 6.5 kg, and elevated serum aspartate aminotransferase or alanine aminotransferase levels above the range of normal. The classification tree yielded a sensitivity of 87.3% and a specificity of 89.3%.

Cholinesterase deficiency and the Churg-Strauss syndrome

We report two patients with the Churg-Strauss syndrome who were found to have decreased cholinesterase activity despite normal phenotypes. Suspicion of abnormal sensitivity to suxamethonium in the first case was raised after prolonged paralysis under anaesthesia. The findings in the second were incidental during the course of intensive care treatment. Both patients received immunosuppressive therapy. Differentiation between the effects of this and the disease process itself cannot be established.

Systemic vasculitis with renal involvement--a review

Twenty five patients with renal vasculitis presenting over an eight year period were reviewed. Ten had microscopic polyarteritis, 6 classic polyarteritis, 5 overlap syndrome, 2 Churg-Strauss syndrome and 2 Wegener's granulomatosis. Clinical features included hypertension, pulmonary involvement, neurological involvement and arthralgia. Serum creatinine was over 500 umol/l in 13 patients, 10 of whom required dialysis. Visceral angiography was positive in 80% of those studied, Focal and segmental necrotising glomerulonephritis was the commonest renal lesion. Treatment consisted of corticosteroids and cytotoxic agents in most cases. Plasmapheresis was used for rapidly progressive renal failure, severe pulmonary haemorrhage or cerebral vasculitis. Improvement or stabilisation of renal function was seen in 68% of patients treated. There were 4 early deaths and one late death. The diagnosis, histology, treatment and outcome of renal vasculitis is discussed. The importance of early diagnosis and treatment is emphasised in this potentially reversible cause of acute renal failure.

Cutaneous polyarteritis nodosa: a clinical and histopathological study of 20 cases

Twenty cases diagnosed as cutaneous polyarteritis nodosa (CPN) and confirmed by skin biopsy over the last 17 years were reviewed in our department. Based upon their clinical features, laboratory findings, and long-term observation of the disease course, they were divided into three groups. 1) Group 1 comprised 16 cases which were classified as the mild cutaneous form. The disease was confined to the skin with occasional involvement of peripheral nerves and skeletal muscles of the affected extremity. They generally followed a benign course. 2) Group 2 comprised 2 cases classified as the severe form. Despite severe clinical manifestations and several abnormal laboratory findings, the disease was limited to the skin, muscles, and peripheral nerves without any visceral involvement over follow-up periods of 11 years and 5 years, respectively. 3) Group 3 comprised 2 cases of the progressive form; in these the disease had begun with a cutaneous lesion and progressed to the systemic form after 19 and 18 year periods of recurrent episodes of cutaneous lesions, respectively. One died of gastrointestinal bleeding. In group 3, serum antinuclear antibodies and rheumatoid factor were positive. The autoimmune mechanism seems to play a role in this group. It is clear from the results of this study that not all patients whose vasculitic lesions are apparently limited to the skin remain in a benign course. Long-term follow-up is essential.

Pulmonary capillaritis and hemorrhage. A clue to the diagnosis of systemic necrotizing vasculitis

Patients with systemic necrotizing vasculitis frequently present as diagnostic dilemmas. In previous series of patients with polyarteritis nodosa, less than one third were diagnosed antemortem. Although current clinical awareness of systemic necrotizing vasculitis is greater than in the past and procedures for the diagnosis of these diseases have improved, patients commonly present with atypical features. The diagnosis of a systemic necrotizing vasculitis frequently remains unsuspected or unproven until an involved tissue is biopsied. We report an unusual case of systemic necrotizing vasculitis in which the diagnosis was confirmed by a transbronchial biopsy of the lung which demonstrated pulmonary capillaritis with hemorrhage.

Cutaneous vasculitis: its relationship to systemic disease

Necrotizing vasculitis may be localized to the skin or may involve multiple organs. Although the etiology of cutaneous necrotizing vasculitis is unknown, evidence suggests that circulating immune complexes play an important role. The most common clinical lesion seen is palpable purpura, which histologically demonstrates leukocytoclastic vasculitis. The majority of patients affected with cutaneous necrotizing vasculitis have a benign course.

Concurrent Churg-Strauss syndrome and temporal arteritis in a young patient with pulmonary nodules

Very few cases of pulmonary vasculitis that cannot be classified into a single category of vasculitis have been described. We report the first case of a vasculitic process in which pulmonary involvement with asthma, eosinophilic interstitial infiltrates, and small nodules were seen in association with jaw claudication and temporal arteritis with giant cells found on biopsy. Other signs of systemic involvement were also present such as peripheral neuropathy, hematuria with erythrocytic casts and proteinuria, pericardial effusion, and a dilated cardiomyopathy. The histopathologic picture was complex and unique. The early age of onset, the multisystemic involvement, and the prompt response to cyclophosphamide pointed to a diagnosis of "polyangiitis overlap syndrome," with some aspects of Churg-Strauss syndrome and also temporal arteritis. Physicians should be aware of these polymorphous and life-threatening pulmonary vasculitic syndromes, which require aggressive immunosuppressor therapy.

Systemic vasculitis in association with human immunodeficiency virus infection

Fourteen cases of vasculitis associated with human immunodeficiency virus infection have thus far been described. Five of these cases may be classified as angiocentric immunoproliferative disorders, including benign lymphocytic angiitis, lymphomatoid granulomatosis, and angiocentric lymphoma. We report a case of benign lymphocytic angiitis of T cell lineage. Extensive studies found no evidence of viral antigens in the inflammatory infiltrates, and immunologic evaluation of the pathologic lesions revealed the infiltrating cells to be predominantly CD3+, CD8+, CD4-. A significant number of these lymphocytes demonstrated a deletion of T cell antigen receptor determinants. We believe that in certain cases of human immunodeficiency virus disease, there occurs a spectrum of lymphoproliferative disorders with angiocentric features that lead to the clinical picture of systemic necrotizing vasculitis. Clinicians should be aware of this association.

Combined sarcoidosis and disseminated visceral giant cell vasculitis

A middle-aged man with only slight symptoms of disease of short duration died suddenly. On autopsy he was found to have not only disseminated visceral giant cell vasculitis with involvement of large and medium-sized arteries and veins, but also sarcoid granulomas in many organs, especially in enlarged mediastinal lymph nodes as well as in several vessel walls. Death was caused by myocardial infarction due to granulomatous vasculitis. This combination of diseases has not previously been described, and the question is whether it represents giant cell arteritis and sarcoidosis, separately, or whether it is a manifestation of a broad spectrum of the same disease.

Isolated necrotizing granulomatous vasculitis of the spermatic cords

Isolated necrotizing granulomatous vasculitis of the spermatic cord has not been described during the last 20 years. We report clinical, laboratory and histopathological features of an instance of contralaterally recurrent lesions of this type in a young photographic laboratory technician. Although to date the disease is considered to be isolated, it may well be a systemic one without yet obvious signs.

The human vasculitis syndromes

The vasculitides consist of a spectrum of clinical syndromes having in common necrotizing inflammation of the vascular system. Typical classification systems are based on both size of vessel involved and clinical gestalt. The author favors a pragmatic classification. Symptoms are manifestations of systemic inflammation and of organ ischemia secondary to inflammatory vascular occlusion. Multicenter studies suggest that the most common vasculitides do not satisfy criteria for one of the specific nosological entities and would be classified as "other" vasculitides. For those syndromes fitting a classical description (e.g., Wegener's, polyarteritis nodosa, Henoch-Schoenlein purpura), therapy is straight-forward. For those defying classification, therapy must be empirically directed at the manifestations causing symptoms.