Validation of the provisional seven-item criteria for the diagnosis of polyarteritis nodosa.

The 1990 American College of Rheumatology (ACR) criteria for the classification of polyarteritis nodosa (PAN) have many pitfalls and performed poorly when used for diagnostic purposes. Recently, a provisional seven-item diagnostic criteria for PAN was proposed. To validate the provisional seven-item diagnostic criteria for PAN in a cohort of PAN patients from a tertiary care centre in India. Clinical details of patients diagnosed as PAN as per the European Medicines Agency algorithm between 2005 and 2020 were collected retrospectively. Age and sex-matched anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) patients were included in the non-PAN group. Patients with a deficiency of adenosine deaminase 2 (DADA2) were included as a separate group. The sensitivity, specificity, positive and negative predictive values (PPV and NPV) for ACR criteria, the Ministry of Health, Labour and Welfare (MHLW) in Japan diagnostic criteria and the seven-item diagnostic criteria were calculated. Thirty-seven PAN, 14 DADA2 and 37 AAV patients were included in the analysis. The sensitivity, specificity, PPV and NPV of the seven-item criteria were 83.7%, 96.8%, 97.3% and 81.1% respectively. For the ACR criteria, sensitivity was 82.9% and specificity was 79.5%. The sensitivity, specificity for MHLW criteria were 77.3% and 90% respectively. The sensitivity and specificity of seven-item criteria for DADA2 patients were 58.8% and 88.2% respectively. There was very poor agreement between the ACR criteria and the seven-item and MHLW criteria and fair agreement between seven-item and MHLW criteria (κ = 0.279). The provisional seven-item criteria for PAN performed well with high specificity and PPV.

Polyarteritis nodosa revisited: a review of historical approaches, subphenotypes and a research agenda.

Polyarteritis nodosa (PAN) is a rare form of primary systemic vasculitis with heterogeneous presentations, treatments and disease course. Historical approaches to classification and diagnostic terminology are reviewed. Since differentiation of PAN from microscopic polyangiitis (MPA) and other ANCA vasculitides by the Chapel Hill conference statements, and with hepatitis associated PAN defined as a secondary vasculitis, the phenotyping and subclassification of PAN has received little attention. Monogenic disorders similar to PAN have been described (familial Mediterranean fever, Adenosine Deaminase-2 deficiency), and cutaneous PAN and single organ vasculitis, discussed. The overlapping phenotypes between PAN and other primary vasculitic syndromes and subphenotypes within PAN are explored. This work will underpin development of newer treatment regimens and future genetic and related aetiologic studies.

The changing face of polyarteritis nodosa and necrotizing vasculitis.

Polyarteritis nodosa (PAN) is a vasculitic disease characterized primarily by necrotizing vasculitis - inflammatory lesions in blood vessels that lead to vessel wall necrosis. Our understanding of PAN and necrotizing vasculitis has evolved over time. In addition to PAN, necrotizing vasculitis is now a recognized feature of a broad range of diseases with different aetiopathogenesis. For example, necrotizing vasculitis associated with hepatitis B virus infection has a different aetiopathogeneis to PAN and is now classified as a separate disease. Additionally, although 'classic' PAN is not an inherited disease, mutations in specific genes, such as ADA2 (also known as CECR1), can result in a necrotizing vasculopathy similar to PAN. The literature also suggests that the course of PAN differs in childhood-onset disease and in cases confined to the skin (so-called cutaneous PAN). Dissecting PAN and other autoinflammatory diseases with PAN-like features has enabled more-specific therapies and might also help us better understand the pathogenesis of these devastating conditions.

Are the 1990 American College of Rheumatology vasculitis classification criteria still valid?

Objectives: Advances in diagnostic techniques have led to better distinction between types of vasculitis, potentially affecting the utility of the 1990 ACR classification criteria for vasculitis. This study tested the performance of these criteria in a contemporary vasculitis cohort. Methods: The Diagnosis and Classification in Vasculitis Study provided detailed clinical, serological, pathological and radiological data from patients with primary systemic vasculitis and clinical context-specific comparator conditions. Fulfilment of six ACR criteria sets and their diagnostic performance was evaluated in patients with a given type of vasculitis and its comparator conditions. Results: Data from 1095 patients with primary systemic vasculitis and 415 with comparator conditions were available. For classification, sensitivities and specificities for ACR classification criteria were, respectively, 81.1% and 94.9% for GCA; 73.6% and 98.3% for Takayasu's arteritis; 65.6% and 88.7% for granulomatosis with polyangiitis; 57.0% and 99.8% for eosinophilic granulomatosis with polyangiitis; 40.6% and 87.8% for polyarteritis nodosa; 28.9% and 88.5% for microscopic polyangiitis; and 72.7% and 96.3% for IgA-vasculitis. Overall sensitivity was 67.1%. Of cases identified by their respective criteria, 16.9% also met criteria for other vasculitides. Diagnostic specificity ranged from 64.2 to 98.9%; overall, 113/415 comparators (27.2%) fulfilled at least one of the ACR classification criteria sets. Conclusion: Since publication of the ACR criteria for vasculitis, the sensitivity for each type of vasculitis, except GCA, has diminished, although the specificities have remained high, highlighting the need for updated classification criteria.

Diagnosis and classification of polyarteritis nodosa.

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis preferentially targeting medium-sized arteries and not associated with glomerulonephritis or small vessel involvement. Anti-neutrophil cytoplasmic antibodies are typically negative. PAN may be triggered by viral infections, particularly hepatitis B virus, but remains idiopathic in most cases. Clinical manifestations of PAN are multisystemic. Peripheral nerve and skin are the most frequently affected tissues. Involvement of the gastrointestinal tract, kidneys, heart, and central nervous system is associated with higher mortality. Laboratory abnormalities reveal a prominent acute phase response but are non-specific. Histologic confirmation of vasculitis in medium sized arteries is desirable and biopsies must be obtained from symptomatic organs if feasible. Skin or muscle and nerve are preferred because of higher diagnostic yield and safety. If biopsies are negative or cannot be obtained, visceral angiography, may reveal multiple micro-aneurysms supporting the diagnosis of PAN. Current treatment policy includes high-dose corticosteroids, which are combined with immunosuppressive agents when critical organ involvement or life-threatening complications occur. IV pulse cyclophosphamide in the remission induction phase, later switched to a safer immunosuppressant for remission maintenance is a frequently used therapeutic approach. A recent consensus algorithm for the classification of PAN has attempted to overcome some of the caveats of the 1990 American College of Rheumatology (ACR) classification criteria which have proven to be unsatisfactory, and has also confirmed the low prevalence of PAN compared to other systemic necrotizing vasculitides. European league against rheumatic diseases (EULAR)/ACR endorsed international cooperation to establish new diagnostic/classification criteria is currently under way.

Uncommon presentations of primary systemic necrotizing vasculitides: the Great Masquerades.

INTRODUCTION: Systemic vasculitides are great masqueraders and at times their presenting manifestations can be very different from the usual recognized patterns. Such uncommon presentations of granulomatosis with polyangiitis (Wegener's granulomatosis), classical polyarteritis nodosa and unclassifiable vasculitides are described here with the relevant review of literature. METHODS: All patients diagnosed as having systemic vasculitides and classified as having granulomatosis with polyangiitis (Wegener's granulomatosis), classic polyarteritis nodosa, microscopic polyangiitis and unclassifiable vasculitis according to EMEA consensus methodology and followed up prospectively from June 2007 to December, 2011 were included. Details of uncommon presentations of these disorders were identified. RESULTS: Seventy-nine patients with systemic vasculitides were seen under our rheumatology services during this period. These included 45 patients with granulomatosis with polyangiitis (Wegener's granulomatosis), 18 with classic polyarteritis nodosa, five with microscopic polyangiitis, four with Churg-Strauss syndrome and seven with unclassifiable vasculitis. The uncommon presentations of granulomatosis with polyangiitis were a tumefactive subcutaneous mass in the thigh; prostatomegaly with obstructive uropathy and advanced renal failure; and predominant gastrointestinal (GI) vasculitis with thrombocytopenia and coagulopathy at presentation. The uncommon manifestations of classic polyarteritis nodosa were secondary antiphospholipid antibody syndrome and Budd-Chiari syndrome. One patient with massive lower GI bleeding required surgical resection of the large bowel which showed isolated necrotizing granulomatous GI vasculitis. Single organ vasculitis of the GI tract was diagnosed. CONCLUSIONS: Systemic necrotizing vasculitides may present with uncommon manifestations and a high index of suspicion is required for early diagnosis and prompt treatment to prevent adverse outcomes.

Validation of the consensus methodology algorithm for the classification of systemic necrotizing vasculitis in Indian patients.

AIM: Many patients with systemic necrotizing vasculitis (SNV) satisfy classification criteria of different disease entities when different classification systems are used. A new classification algorithm has been proposed recently by using the American College of Rheumatology criteria, Chapel Hill Consensus Criteria (CHCC) and Sorensen surrogate markers for a more uniform classification of patients suffering from these rare disorders. METHODS: We applied this algorithm to patients diagnosed as having systemic vasculitis between 2007 and 2011. We also analyzed the data using this algorithm by incorporating the recently proposed revised CHCC nomenclature of vasculitis in place of the older criteria. RESULTS: Seventy-nine patients with SNV were studied. One patient diagnosed as microscopic polyangiitis (MPA) had to be excluded from analysis as she had previously been diagnosed as having Behcet's disease. All patients of eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA) and MPA were reclassified to the same diagnostic subcategory after application of the algorithm. Three (16.7%) of 18 polyarteritis nodosa patients were unclassifiable after application of the consensus algorithm while two (11.1%) were reclassified as MPA. All previously unclassifiable patients could be classified either as MPA or GPA after application of the new algorithm. There was no difference in the results when the CHCC 2012 nomenclature was used instead of the older CHCC in the consensus algorithm. CONCLUSION: The new classification algorithm is a reliable method for classification of SNV for epidemiological purposes in our population.

[How to treat systemic necrotizing vasculitides?]. / Comment traiter une vascularite nécrosante ?

Corticosteroids and, according to severity or vasculitis type, cytotoxic agents are prescribed to treat systemic necrotizing vasculitides. Usually, in most vasculitides, treatment is prescribed for at least 18 months. Treatment is able to obtain a remission in approximatively 90% of patients. Relapse rate is high. Cyclophosphamide is usually prescribed for a few months, and administered by pulses. A maintenance treatment is compulsory and comprises usually azathioprine and methotrexate. Biologics can be proposed as ad on therapy like intravenous immunoglobulins and anti-TNF. Rituximab, an anti-CD20 drug is as effective as cyclophosphamide. It can be also prescribed to maintain remission.

Treating polyarteritis nodosa: current state of the art.

Defining treatment guidelines for polyarteritis nodosa (PAN) is complicated by the evolving definition and classification of this vasculitis, and because clinical trials have included patients with PAN, microscopic polyangiitis or, sometimes, Churg-Strauss syndrome. Nonetheless, clinical trial data support that the 'idiopathic generalised' form of PAN benefits from a severity-adapted treatment strategy, implying that cases with life-threatening manifestations require a regimen combining high-dose glucocorticoids and cyclophosphamide, whereas a non-severe disease may be treated with glucocorticoids alone. Results of uncontrolled studies indicate that hepatitis B virus-associated PAN management should include an antiviral agent, short-term glucocorticoids and plasma exchanges. No robust scientific evidence is available to guide the treatment of the limited variant 'cutaneous PAN'. Most experts recommend a less aggressive therapy with non-steroidal anti-inflammatory drugs or other agents, such as colchicine or dapsone. PAN has become an even more uncommon disease, probably due to classification changes and, perhaps also to a genuine modification of the epidemiology of this vasculitis. Although more data are needed to resolve outstanding questions, it is unclear whether all these matters can be studied in the future in large, sufficiently powered trials.

EULAR/PRINTO/PRES criteria for Henoch-Schönlein purpura, childhood polyarteritis nodosa, childhood Wegener granulomatosis and childhood Takayasu arteritis: Ankara 2008. Part II: Final classification criteria.

OBJECTIVES: To validate the previously proposed classification criteria for Henoch-Schönlein purpura (HSP), childhood polyarteritis nodosa (c-PAN), c-Wegener granulomatosis (c-WG) and c-Takayasu arteritis (c-TA). METHODS: Step 1: retrospective/prospective web-data collection for children with HSP, c-PAN, c-WG and c-TA with age at diagnosis

EULAR/PRINTO/PRES criteria for Henoch-Schönlein purpura, childhood polyarteritis nodosa, childhood Wegener granulomatosis and childhood Takayasu arteritis: Ankara 2008. Part I: Overall methodology and clinical characterisation.

OBJECTIVES: To report methodology and overall clinical, laboratory and radiographic characteristics for Henoch-Schönlein purpura (HSP), childhood polyarteritis nodosa (c-PAN), c-Wegener granulomatosis (c-WG) and c-Takayasu arteritis (c-TA) classification criteria. METHODS: The preliminary Vienna 2005 consensus conference, which proposed preliminary criteria for paediatric vasculitides, was followed by a EULAR/PRINTO/PRES - supported validation project divided into three main steps. Step 1: retrospective/prospective web-data collection for HSP, c-PAN, c-WG and c-TA, with age at diagnosis

Treatment of polyarteritis nodosa and microscopic polyangiitis without poor-prognosis factors: A prospective randomized study of one hundred twenty-four patients.

OBJECTIVE: To assess the efficacy of systemic corticosteroids alone as first-line treatment of polyarteritis nodosa (PAN) and microscopic polyangiitis (MPA) without poor-prognosis factors as defined by the Five-Factors Score (FFS), and to compare the efficacy and safety of azathioprine versus pulse cyclophosphamide as adjunctive immunosuppressive therapy for patients experiencing treatment failure or relapse. METHODS: This prospective, multicenter, therapeutic trial included 124 patients with newly diagnosed PAN or MPA (FFS of 0) treated with corticosteroids alone. At the time of treatment failure or disease relapse, patients were randomized to receive 6 months of therapy with oral azathioprine or 6 pulses of cyclophosphamide. Analyses was performed according to an intent-to-treat strategy. RESULTS: The mean +/- SD followup period was 62 +/- 33 months. Treatment with corticosteroids alone induced remission in 98 patients; 50 (40%) of these patients had sustained disease remission, 46 (37%) experienced a relapse, and 2 became corticosteroid dependent (daily prednisone dose > or = 20 mg). In 26 patients (21%), treatment with corticosteroids alone failed, and 49 patients (40%) required additional immunosuppression. Among the 39 patients randomized, 13 of 19 achieved remission with cyclophosphamide pulses, and 14 of 20 achieved remission with azathioprine. Among all patients, the 1-year and 5-year survival rates were 99% and 92%, respectively. Six deaths occurred in the cyclophosphamide-treated group compared with 2 deaths in the azathioprine-treated group. Disease-free survival was significantly lower for patients with MPA than for those with PAN (P = 0.046). CONCLUSION: For patients with PAN or MPA with an FFS of 0, overall 5-year survival was good, but first-line corticosteroid treatment was able to achieve and maintain remission in only about half of the patients, and 40% of the patients required additional immunosuppressive therapy. Azathioprine or pulse cyclophosphamide was fairly effective for treating corticosteroid-resistant disease or major relapses.

Medium-size-vessel vasculitis.

Medium-size-artery vasculitides do occur in childhood and manifest, in the main, as polyarteritis nodosa (PAN), cutaneous PAN and Kawasaki disease. Of these, PAN is the most serious, with high morbidity and not inconsequential mortality rates. New classification criteria for PAN have been validated that will have value in epidemiological studies and clinical trials. Renal involvement is common and recent therapeutic advances may result in improved treatment options. Cutaneous PAN is a milder disease characterised by periodic exacerbations and often associated with streptococcal infection. There is controversy as to whether this is a separate entity or part of the systemic PAN spectrum. Kawasaki disease is an acute self-limiting systemic vasculitis, the second commonest vasculitis in childhood and the commonest cause of childhood-acquired heart disease. Renal manifestations occur and include tubulointerstitial nephritis and renal failure. An infectious trigger and a genetic predisposition seem likely. Intravenous immunoglobulin (IV-Ig) and aspirin are effective therapeutically, but in resistant cases, either steroid or infliximab have a role. Greater understanding of the pathogenetic mechanisms involved in these three types of vasculitis and better long-term follow-up data will lead to improved therapy and prediction of prognosis.

Evaluation of a new algorithm in classification of systemic vasculitis.

OBJECTIVE: Recently, a new consensus algorithm for classification of ANCA-associated vasculitis (AAV) and PAN had been proposed by Watt et al. for epidemiological studies. In order to evaluate this algorithm, the current study used the algorithm to reclassify the patients with AAV and PAN in our centre. METHODS: Five hundred and fifty Chinese patients with primary systemic vasculitis diagnosed in our referral diagnostic centre during the past 10 years were retrospectively studied. Four hundred and ninety-three out of 550 were ANCA positive. We compared the new consensus algorithm and the 1994 Chapel Hill Consensus Conference (CHCC) definitions supplemented with surrogate parameters, in the same cohort of patients with primary systemic vasculitis. RESULTS: Applying the CHCC definitions with surrogate parameters, the diagnoses were Churg-Strauss syndrome (CSS) (n = 0), WG (n = 127), microscopic polyangiitis (MPA) (n = 363), PAN (n = 4) and unclassified (n = 56). Using the new consensus algorithm, the diagnoses were CSS (n = 2), WG (n = 199), MPA (n = 329), PAN (n = 0) and unclassified (n = 20). CONCLUSIONS: Watts' algorithm was a useful method to classify patients into a single category, with less unclassified patients and without overlapping diagnosis, which allows their use in epidemiological studies.