Evaluation of the Sørensen diagnostic criteria in the classification of systemic vasculitis

Evaluation of the ACR/EULAR 2022 criteria for classification of ANCA-associated vasculitis in a population-based cohort from Sweden

OBJECTIVE

To evaluate the ACR/EULAR 2022 criteria for ANCA-associated vasculitides (AAV) classification and compare them with the European Medicines Agency (EMA) algorithm and with classification based only on ANCA serology.

METHODS

In the analysis, 374 cases (47% female) were classified according to the EMA algorithm, ANCA serology and ACR/EULAR criteria. The agreement rate was calculated using the kappa (κ) statistic.

RESULTS

Under EMA, 192 patients were classified as granulomatosis with polyangiitis (GPA), 159 as microscopic polyangiitis (MPA) and 23 as eosinophilic granulomatosis with polyangiitis (EGPA). The ACR/EULAR criteria classified 199 patients as GPA, 136 as MPA and 22 as EGPA. Four patients (1.1%) met criteria of two disease categories, and 13 (3.5%) were unclassifiable. The observed agreement between EMA and ACR/EULAR was 85% for GPA, 75% for MPA and 96% for EGPA. The unweighted κ statistic was 0.66 (95% CI: 0.60, 0.74). Of the 188 PR3-ANCA positive patients, 186 (98.9%) were classified as GPA using ACR/EULAR criteria, and 135 of 161 (83.9%) MPO-ANCA positive patients were classified as MPA. With a classification solely based on ANCA specificity, agreement with ACR/EULAR was 99% for GPA and 88% for MPA.

CONCLUSIONS

EMA and ACR/EULAR classification give similar results. A small proportion of patients cannot be classified or fall into two categories. Some patients exhibiting granuloma, a key feature of GPA, are nevertheless classified as MPA, conflicting with the current view of histopathology of AAV. There is high agreement of ANCA-based classification with that of ACR/EULAR, reflected in the considerable weight granted to ANCA in the new criteria. These crucial elements within the new criteria necessitate a consensus discussion among field experts.

Polyangiitis overlap syndrome: a rare clinical entity

Polyangiitis overlap syndrome is a rare clinical entity comprising patients with overlapping features of more than one vasculitis, usually eosinophilic granulomatosis with polyangiitis (EGPA) and granulomatosis with polyangiitis (GPA). Few cases of polyangiitis overlap syndrome have been described in the literature, mostly associated with c-ANCA, anti-proteinase (PR)-3 positivity, a protean clinical picture characterized by vasculitis, eosinophilia and eosinophilic infiltrates in tissues and a favorable response to steroids and immunosuppressant treatments. Herein, we present a case of a 66-year-old woman with nasal obstruction, external nose deformity, sensorineural hearing loss, peripheral blood eosinophilia, high titer anti-PR3 antibodies and lung involvement. Nasal septum biopsies showed inflammatory infiltrate with eosinophilic component; histopathology of the lung demonstrated necrotizing granulomas associated with inflammatory infiltrate composed of numerous neutrophils and some eosinophils. The patient was diagnosed with polyangiitis overlap syndrome and successfully treated with cyclophosphamide. Recognizing this entity is fundamental given the distinct clinical phenotype and outcomes to therapy in the complex scenario of ANCA-associated vasculitides.

ANCA-Associated Vasculitis in Latin America: A Systematic Literature Review: About Their Epidemiology and Their Clinical Features

ABSTRACT

Most of the existing literature, including epidemiological studies and clinical trials, on antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) include North American (mainly United States and Canada), European, and Asian populations. Few studies have focused on multiethnic populations such as the one from Latin America. Racial and ethnic differences in the incidence of AAV could partially explain the comparatively low number of AAV studies originating in Latin America. However, given the racial/ethnic diversity as well as socioeconomic differences existing in this region, better reporting of AAV presentations and outcomes in Latin America could highlight valuable gaps on the understanding and treatment of these patients. Recently, larger case series and studies have provided better clinical information regarding AAV patients in Latin American countries; however, further information is needed to address gaps such as risk factors, genetic profiles, clinical features, and predictors of clinical outcomes. For these reasons, we have performed a systematic literature review to enhance our understanding of AAV patients in Latin America. We have included 11 articles focused on the epidemiological and clinical features of AAV in Latin America; some similarities and differences with AAV in other regions are shown in these articles. We have identified differences in their prevalence across Latin American countries, which may reflect reporting bias or true ethnic differences among the countries. Our findings should encourage further investigation into AAV in Latin America; such studies will hopefully lead to the optimal management of these patients.

Polyangiitis overlap syndrome: a novel presentation of microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis

Polyangiitis overlap syndrome (POS) is a diagnostic term coined by Leavitt and Fauci that characterises patients with overlapping features of more than one vasculitis. Prior case studies of antineutrophil cytoplasmic antibodies (ANCA)-associated POS have only been published in patients with eosinophilic granulomatosis with polyangiitis (EGPA) and granulomatosis with polyangiitis alongside proteinase-3/cytoplasmic (C)-ANCA positivity. We present a case of a 60-year-old woman with dyspnoea, hemoptysis, positive perinuclear-ANCA and renal biopsy demonstrating evidence of microscopic polyangiitis. In addition, our patient also had asthma, mononeuritis multiplex, eosinophilia and migratory pulmonary infiltrates, thus fulfilling the criteria for EGPA. This novel case report suggests that POS is not limited to C-ANCA positivity and has variable presentations.

The complexity of classifying ANCA-associated small-vessel vasculitis in actual clinical practice: data from a multicenter retrospective survey

The different sets of criteria for diagnosis or classification of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) lead to numerous overlapping and reclassified diagnoses in clinical practice. We designed this study to assess the difficulties in classifying patients with AAV. As a secondary objective, different variables were tested to predict prognosis. We conducted a retrospective chart review in a Western Spain multicentre survey. A total of 115 adult patients diagnosed with AAV from 2002 to 2013 and followed for at least 3 years were included. They were classified according to (1) Chapel Hill Consensus Conference (CHCC), (2) European Medicines Agency algorithm and (3) French Vasculitis Study Group/European Vasculitis Society phenotypes. Fifty-three patients (46%) had neither distinctive histopathological data of a single AAV definition nor any surrogate markers for granulomatous inflammation and thus did not fulfill any diagnostic criteria. Ocular, ear, nose, throat, skin, and lung involvement were more frequent with proteinase 3 (PR3) antibodies, whereas peripheral neuropathy was more frequent with myeloperoxidase (MPO) antibodies. When the disease was severe at diagnosis, the HR for mortality was 10.44. When induction treatment was not given in accordance with the guidelines, the HR for mortality was 4.00. For maintenance treatment, the HR was 5.49 for mortality and 2.48 for relapse. AAV classification is difficult because many patients had neither specific clinical data nor distinctive histological features of a single CHCC definition. A structured clinical assessment of patient severity is the best tool to guide the management of AAV.

A rare case report of polyangiitis overlap syndrome: granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis

Background

Granulomatosis with polyangiitis (GPA) is a systemic ANCA-associated vasculitis characterized by necrotizing granulomatous inflammation and a predilection for the upper and lower respiratory tract. Eosinophilic granulomatosis with polyangiitis (EGPA) is also a systemic ANCA-associated vasculitis, but EGPA is characterized by eosinophilic as well as granulomatous inflammation and is more commonly associated with asthma and eosinophilia.

Polyangiitis overlap syndrome is defined as systemic vasculitis that does not fit precisely into a single category of classical vasculitis classification and/or overlaps with more than one category. Several polyangiitis overlap syndromes have been identified, however, there are very few case reports of an overlap syndrome involving both GPA and EGPA in the medical literature.

Case presentation

We conducted a PUBMED literature review using key words ‘granulomatosis with polyangiitis,’ ‘Wegener’s,’ ‘GPA,’ ‘eosinophilic granulomatosis with polyangiitis,’ ‘Churg-Strauss,’ ‘EGPA,’ ‘overlap syndrome,’ ‘Wegener’s with eosinophilia,’ and ‘GPA with eosinophilia’ in English only journals from 1986 to 2017. Relevant case reports and review articles of overlap syndromes of GPA and EGPA were identified. We aim to report a unique case of GPA and EGPA overlap syndrome and review the cases that have been previously described.

Between 1986 and 2017, we identified 15 cases that represent an overlap syndrome with compelling features of both GPA and EGPA. Patients ranged in age between 21 and 78. Of those whose gender was identified, 80 % of the patients were female. All cases described involved the lungs, 60 % reported sinus involvement, and more than 50 % displayed renal involvement. An overwhelming majority of patients were positive for c-ANCA and demonstrated eosinophilia (peripheral blood or tissue eosinophilia). A preponderance of the cases described were treated with systemic corticosteroids combined with an immunosuppressive/cytotoxic agents.

Conclusion

To our knowledge, there have been very few cases reported of an overlap syndrome of GPA and EGPA. Identification of patients with a polyangiitis overlap syndrome of GPA and EGPA is imperative as prognosis, longitudinal management and treatment modalities may differ between these entities.

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.

Current concept and epidemiology of systemic vasculitides

Although a new classification algorithm for systemic vasculitides was proposed by Watts et al. and the Chapel Hill Consensus Conference (CHCC) was updated in 2012, there are currently no validated diagnostic criteria for systemic vasculitides. The Diagnostic and Classification Criteria for Vasculitis study (DCVAS) is a global study to develop and improve the diagnostic criteria for systemic vasculitides. The epidemiology of systemic vasculitides differs widely among countries. For example, in the case of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, patients with microscopic polyangiitis (MPA) and with positivity for MPO-ANCA are predominant in Asian countries, whereas patients with granulomatosis with polyangiitis (GPA) and with positivity for PR3-ANCA are predominant in northern Europe and the United States. Interstitial lung disease (ILD) occurs more frequently in Asian patients compared with patients in Europe. The incidence and the prevalence of large-vessel vasculitis also differ significantly. Giant cell arteritis (GCA) occurs frequently in northern Europe, unlike Takayasu arteritis (TAK). The ethnic and regional differences in the incidence, prevalence and clinical characteristics of patients with vasculitis should be recognized when we diagnose and treat patients with vasculitis using criteria, and should also be considered when interpreting the results from clinical studies.

The immunopathology of ANCA-associated vasculitis

The small-vessel vasculitides are a group of disorders characterised by variable patterns of small blood vessel inflammation producing a markedly heterogeneous clinical phenotype. While any vessel in any organ may be involved, distinct but often overlapping sets of clinical features have allowed the description of three subtypes associated with the presence of circulating anti-neutrophil cytoplasmic antibodies (ANCA), namely granulomatosis with polyangiitis (GPA, formerly known as Wegener’s Granulomatosis), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (eGPA, formerly known as Churg-Strauss syndrome). Together, these conditions are called the ANCA-associated vasculitidies (AAV). Both formal nomenclature and classification criteria for the syndromes have changed repeatedly since their description over 100 years ago and may conceivably do so again following recent reports showing distinct genetic associations of patients with detectable ANCA of distinct specificities. ANCA are not only useful in classifying the syndromes but substantial evidence implicates them in driving disease pathogenesis although the mechanism by which they develop and tolerance is broken remains controversial. Advances in our understanding of the pathogenesis of the syndromes have been accompanied by some progress in treatment, although much remains to be done to improve the chronic morbidity associated with the immunosuppression required for disease control.

Classification of ANCA-associated vasculitis

Classification of the ANCA-associated vasculitides remains controversial. Existing systems, developed by the American College of Rheumatology (ACR) in 1990, the Chapel Hill Consensus Conference (CHCC) in 1994 and updated in 2012, and the European Medicines Agency algorithm, all have deficiencies, especially when applied to unselected patients. The ACR system did not include ANCA or microscopic polyangiitis, and the CHCC (1994) included MPA but not ANCA (this was rectified in the 2012 revision). These systems were developed as classification criteria and not as diagnostic criteria. There are currently no validated diagnostic criteria for AAV. The Diagnostic and Classification Criteria for Vasculitis (DCVAS) study is a global study with the objective of developing and validating diagnostic criteria.

Critical appraisal of classification criteria for vasculitides

The vasculitides are a group of protean diseases, some of which are caused by conditions including infections, other autoimmune diseases, or neoplasias. They are a challenge to the clinician, in terms of both diagnosis and therapy. No diagnostic criteria exist, although a multinational effort to develop them is in progress. However, many classification criteria have been proposed, and these have served as diagnostic surrogates and have made it possible to discriminate between many, although not all, of the vasculitides, mainly for epidemiological and therapeutic trial design purposes. In this review we recognise the difficulties of defining such criteria, but at the same time attempt to provide a critical overview of efforts to do so. The increasing knowledge regarding many of these diseases makes us confident that the time will come when their aetiology, or at least their main pathogenic features, is known, rendering proposed classification criteria obsolete.

Nonarteriosclerotic vascular disease

Thromboangiitis obliterans, or Buerger disease, is a chronic nonatherosclerotic endarteritis manifesting as inflammation and thrombosis of distal extremity small and medium-sized arteries resulting in relapsing episodes of distal extremity ischemia. Takayasu arteritis is a rare syndrome characterized by inflammation of the aortic arch, pulmonary, coronary, and cerebral vessels, presenting with cerebrovascular symptoms, myocardial ischemia, or upper extremity claudication in young, often female, patients. Kawasaki disease is a small- and medium-vessel acute systemic vasculitis of young children, with morbidity and mortality stemming from coronary artery aneurysms. Microscopic polyangiitis, Churg-Strauss syndrome, and Wegener granulomatosis are systemic small-vessel vasculitides, affecting arterioles, capillary beds and venules, and each presenting with variable effects on the pulmonary, renal and gastrointestinal systems.

Pathological features of classical polyarteritis nodosa: analysis of 19 autopsy cases

Classical polyarteritis nodosa (cPN) is a rare autoimmune disease featuring systemic inflammation of middle- and small-sized arteries. Because most of autopsy cases underwent clinical treatment, arterial fibrinoid necrosis, which is the most specific finding of cPN, is often obscure. The aim of this study was to seek morphological characteristics of the middle-sized arteries in autopsy cases of cPN, and to identify immunohistochemical markers for the diagnosis of cPN. Nineteen patients who had undergone autopsy with a diagnosis of cPN were enrolled. Twenty-one autopsy cases without cPN were examined as control group. Arterial fibrinoid necrosis in medium-sized arteries was observed in 8/19 autopsy cases. Elastica van Gieson staining showed an increased number of elastic fiber layers (P<0.0001) and greater distances between elastic fiber layers (P<0.0001) in the renal middle-sized arteries of the cPN group. These findings probably reflected the post-inflammatory remodeling process after necrotizing vasculitis. On immunohistochemical examination, the cPN group showed high matrix metalloproteinase-1 and tumor necrosis factor-α expressions and decreased smoothelin expression in the vascular wall compared to the control group. When uncertain or atypical autopsy cases of cPN are examined, these findings can help to make the pathological diagnosis of cPN.

Differentiation between Wegener's granulomatosis and microscopic polyangiitis by an artificial neural network and by traditional methods

OBJECTIVE

To investigate the operating characteristics of the American College of Rheumatology (ACR) traditional format criteria for Wegener's granulomatosis (WG), the Sørensen criteria for WG and microscopic polyangiitis (MPA), and the Chapel Hill nomenclature for WG and MPA. Further, to develop and validate improved criteria for distinguishing WG from MPA by an artificial neural network (ANN) and by traditional approaches [classification tree (CT), logistic regression (LR)].

METHODS

All criteria were applied to 240 patients with WG and 78 patients with MPA recruited by a multicenter study. To generate new classification criteria (ANN, CT, LR), 23 clinical measurements were assessed. Validation was performed by applying the same approaches to an independent monocenter cohort of 46 patients with WG and 21 patients with MPA.

RESULTS

A total of 70.8% of the patients with WG and 7.7% of the patients with MPA from the multicenter cohort fulfilled the ACR criteria for WG (accuracy 76.1%). The accuracy of the Chapel Hill criteria for WG and MPA was only 35.0% and 55.3% (Sørensen criteria: 67.2% and 92.4%). In contrast, the ANN and CT achieved an accuracy of 94.3%, based on 4 measurements (involvement of nose, sinus, ear, and pulmonary nodules), all associated with WG. LR led to an accuracy of 92.8%. Inclusion of antineutrophil cytoplasmic antibodies did not improve the allocation. Validation of methods resulted in accuracy of 91.0% (ANN and CT) and 88.1% (LR).

CONCLUSION

The ACR, Sørensen, and Chapel Hill criteria did not reliably separate WG from MPA. In contrast, an appropriately trained ANN and a CT differentiated between these disorders and performed better than LR.

Recent aspects of vasculitis and future direction

Vasculitis is pathologically identified as specific cellular inflammation, vessel destruction, and tissue necrosis. Current classifications of vasculitis such as the Chapel Hill Classification (CHCC) and American College of Rheumatology (ACR) guidelines are not sufficiently adequate for clinicians to diagnose vasculitis. The biomarkers that are currently in clinical use such as PR3-ANCA and MPO-ANCA, only help in diagnosing small vessel vasculitis and their sensitivity and specificity are not sufficient. However, recent developments related to the pathogenesis and etiopathogenesis of vasculitis have the potential to contribute to new and improved biomarkers. The determination of diverse roles of ANCA and synergistic effects of infection, genetic, environmental factors and drugs on pathogenesis is quite important. The demonstration of a new autoantibody directed to hLAMP-2 and the resemblance to some microbial structures, in addition to the determination of the possible roles of hepatitis B and C on vasculitis are important findings. These hints may lead to new biomarker developments, providing a better method to diagnose vasculitis. The evidence on T cell immunity as circulatory and lesional will likely contribute to the development of new drugs for vasculitis.

EULAR points to consider in the development of classification and diagnostic criteria in systemic vasculitis

OBJECTIVES

The systemic vasculitides are multiorgan diseases where early diagnosis and treatment can significantly improve outcomes. Robust nomenclature reduces diagnostic delay. However, key aspects of current nomenclature are widely perceived to be out of date, these include disease definitions, classification and diagnostic criteria. Therefore, the aim of the present work was to identify deficiencies and provide contemporary points to consider for the development of future definitions and criteria in systemic vasculitis.

METHODS

The expert panel identified areas of concern within existing definitions/criteria. Consequently, a systematic literature review was undertaken looking to address these deficiencies and produce 'points to consider' in accordance with standardised European League Against Rheumatism (EULAR) operating procedures. In the absence of evidence, expert consensus was used.

RESULTS

There was unanimous consensus for re-evaluating existing definitions and developing new criteria. A total of 17 points to consider were proposed, covering 6 main areas: biopsy, laboratory testing, diagnostic radiology, nosology, definitions and research agenda. Suggestions to improve and expand current definitions were described including the incorporation of anti-neutrophil cytoplasm antibody and aetiological factors, where known. The importance of biopsy in diagnosis and exclusion of mimics was highlighted, while equally emphasising its problems. Thus, the role of alternative diagnostic tools such as MRI, ultrasound and surrogate markers were also discussed. Finally, structures to develop future criteria were considered.

CONCLUSIONS

Limitations in current classification criteria and definitions for vasculitis have been identified and suggestions provided for improvement. Additionally it is proposed that, in combination with the updated evidence, these should form the basis of future attempts to develop and validate revised criteria and definitions of vasculitis.

Late onset of pANCA renal and pulmonary vasculitis in a girl affected by undifferentiated connective tissue disease

Vasculitides are clinicopathologic entities characterized by inflammation and damage of blood vessels. They are heterogeneous diseases related to immunopathogenetic mechanisms. For example, anti-neutrophil cytoplasmic autoantibodies directed against perinuclear or cytoplasmic proteins of neutrophils are present in a high percentage of patients with systemic vasculitis, and they can be suggestive of Wegener's Granulomatosis and Microscopic Polyangiitis. This case report underlines the necessity of more specific laboratory and instrumental testing if clinical signs and/or other parameters (p-ANCA and/or c-ANCA staining and/or urinalysis) are suggestive of systemic vasculitis.

Churg-Strauss angiitis

Churg-Strauss angiitis or syndrome (CSA) is defined as an eosinophil-rich and granulomatous inflammation involving the respiratory tract, and necrotising vasculitis affecting small- to medium-sized vessels, and is associated with asthma and eosinophilia. It is usually classified among the so-called anti-neutrophil antibody (ANCA)-associated systemic vasculitides (AASVs) because of its clinical and pathological features that overlap with those of the other AASVs. However, two recent studies on large cohorts of patients have found that ANCAs, usually P-ANCAs/MPO-ANCAs, were present in only 38% of patients. Moreover, the ANCA status was shown to segregate with clinical phenotype. ANCA-positive patients were significantly more likely to have disease manifestations associated with small-vessel vasculitis, including necrotising glomerulonephritis, mononeuritis and purpura, whereas ANCA-negative cases were significantly more likely to have cardiac and lung involvement. Vasculitis was documented less frequently in histological specimens from ANCA-negative patients in comparison with ANCA-positive ones. These findings have led to postulate the predominance of distinct pathogenetic mechanisms in the two subsets of patients: an ANCA-mediated process in ANCA-positive patients and tissue infiltration by eosinophils with subsequent release of toxic product in ANCA-negative cases. Preliminary results suggest that ANCA-positive and ANCA-negative patients also might have a different genetic background. Corticosteroids remain the cornerstone of the initial treatment of CSA. The addition of cyclophosphamide is indicated in treatment of patients with poor-prognosis factors or in patients without poor-prognosis factors but those that are prone to relapses. The length of the maintenance therapy remains to be established. However, the vast majority of patients require long-term corticosteroids treatment to control asthma.

Recent developments in the classification and assessment of vasculitis

The systemic vasculitides are a group of multisystem diseases characterized by inflammation of blood vessels. The aetiopathogenesis is unknown, and therefore nomenclature and classification are often descriptive and based on pathological features. Generally agreed classification schemes are vital to enable large multicentre or multinational clinical trials to be undertaken. An algorithm has recently been developed to harmonize use of the American College of Rheumatology (ACR) 1990 criteria and the Chapel Hill Consensus Conference definitions. Despite this, a revision of the classification criteria is still needed, and diagnostic criteria need to be developed ab initio. The very complexity of the diseases makes accurate objective assessment critical, especially for the conduct of clinical trials. Several standardized assessment tools for both disease activity and damage have been developed over the past two decades and are now widely used in both clinical trials and routine practice. A second generation of tools is now under development.

Cocaine-related peripheral vascular occlusive disease treated with iloprost in addition to anticoagulants and antibiotics

We describe a case of acute ischemia of the 2nd, 3rd and 4th fingers of the right hand secondary to peripheral vascular occlusive disease induced by repeated intra-arterial cocaine injections. The complete occlusion of the distal arteries resolved following treatment with iloprost, a synthetic stable analogue of prostacyclin PGI2, in addition to anticoagulants and antibiotics.

Wegener's granulomatosis: an update on diagnosis and therapy

Wegener's granulomatosis (WG) is a unique clinicopathological disease characterized by necrotizing granulomatous vasculitis of the respiratory tract, pauci-immune necrotizing glomerulonephritis and small-vessel vasculitis. Owing to its wide range of clinical manifestations, WG has a broad spectrum of severity that includes the potential for alveolar hemorrhage or rapidly progressive glomerulonephritis, which are immediately life threatening. WG is associated with the presence of circulating antineutrophil cytoplasm antibodies (c-ANCAs). The most widely accepted pathogenetic model suggests that c-ANCA-activated cytokine-primed neutrophils induce microvascular damage and a rapid escalation of inflammation with recruitment of mononuclear cells. The diagnosis of WG is made on the basis of typical clinical and radiologic findings, by biopsy of involved organ, the presence of c-ANCA and exclusion of all other small-vessel vasculitis. Currently, a regimen consisting of daily cyclophosphamide and corticosteroids is considered standard therapy. A number of trials have evaluated the efficacy of less-toxic immunosuppressants and antibacterials for treating patients with WG, resulting in the identification of effective alternative regimens to induce or maintain remission in certain subpopulations of patients. Recent investigation has focused on other immunomodulatory agents (e.g., TNF-alpha inhibitors and anti-CD20 antibodies), intravenous immunoglobulins and antithymocyte globulins for treating patients with resistant WG.

A paradigm of diagnostic criteria for polyarteritis nodosa: analysis of a series of 949 patients with vasculitides

OBJECTIVE

To establish a set of clinical and paraclinical criteria potentially useful as a diagnostic screening tool for polyarteritis nodosa (PAN).

METHODS

The abilities of individual descriptive items to predict a diagnosis of PAN were evaluated by screening available data from 949 patients from the French Vasculitis Study Group database, including 262 with PAN and 687 with control vasculitides. Selected items were tested in a logistic regression model to establish a minimal set of nonredundant PAN-predictive criteria. The discriminative accuracy of these items and of the American College of Rheumatology (ACR) 1990 criteria were assessed by reapplying them to the initial patient sample and a subgroup restricted to PAN and microscopic polyangiitis (MPA) patients. A computer simulation procedure was conducted on artificially generated patient data to evaluate the usefulness of these criteria in predicting a diagnosis of PAN.

RESULTS

The analysis resulted in the retention of 3 positive predictive parameters (hepatitis B virus antigen and/or DNA in serum, arteriographic anomalies, and mononeuropathy or polyneuropathy) and 5 negative predictive parameters (indirect immunofluorescence detection of antineutrophil cytoplasmic antibody; asthma; ear, nose, and throat signs; glomerulopathy; and cryoglobulinemia) for the criteria set. These criteria yielded 70.6% sensitivity for all control vasculitides and 89.7% for MPA controls, with 92.3% specificity for all controls and 83.1% for MPA controls. The discriminant abilities of this set of items outperformed the ACR 1990 criteria in all analytical situations, showing better robustness to variations in the prevalence of individual vasculitides.

CONCLUSION

The use of positive and negative discriminant criteria could constitute a sound basis for developing a diagnostic tool for PAN to be used by clinicians. Further prospective analyses and validations in different populations are needed to confirm these items as satisfactory diagnostic criteria.

Spectrum of cutaneous vasculitis in adult patients from the Farwaniya region of Kuwait

OBJECTIVE

To determine the clinical profile, etiologic factors, disease associations, and the laboratory profile of adult patients with cutaneous leukocytoclastic vasculitis (LV) presenting to the Dermatology Department at Farwaniya Hospital, Kuwait.

SUBJECTS AND METHODS

The medical records of 57 adult patients (>18 years) with biopsy-proven cutaneous LV from January 2004 to June 2006 at Farwaniya Hospital were reviewed.

RESULTS

Of the 57 patients studied, 21 (36.8%) were classified as having primary cutaneous small vessel vasculitis. The most common type of skin lesions found was palpable purpura seen in 29 (50.9%) patients. No possible cause for the cutaneous vasculitis could be identified in 21 patients. Extracutaneous involvement was seen in 32 (56.1%) patients of which 29 had joint involvement. The most frequent laboratory abnormality was an elevated erythrocyte sedimentation rate (ESR). Altered laboratory evaluation in the form of leukocytosis, raised antistreptolysin O titers and urine abnormalities were found in association with systemic vasculitis. IgA deposits were present in 33 patients. Risk factors for chronicity of cutaneous LV were female sex, advanced age, unidentified etiology, absence of fever and presence of joint involvement.

CONCLUSION

The commonest type of LV in Kuwait is primary cutaneous small vessel vasculitis. The most frequent laboratory abnormality associated with LV was increased ESR.

Nosology of primary vasculitis

PURPOSE OF REVIEW

Recent developments in the nosology of primary systemic vasculitis are placed in the context of an historical overview. The ongoing attempts to develop criteria for classification and diagnosis are discussed.

RECENT FINDINGS

Giant cell arteritis has supplanted temporal arteritis as the preferred term for chronic granulomatous arteritis in older adults. A new classification system for childhood vasculitis has been proposed by a European collaborative group. A study of idiopathic polyarteritis nodosa demonstrates greater similarity to microscopic polyangiitis in relapse rate than previously reported. Controversy has arisen over the eponym Wegener's granulomatosis because of alleged involvement of Friedrich Wegener in the Nazi regime during World War II. Diagnostic criteria for Kawasaki disease are problematic because many patients with coronary artery involvement do not fulfill current criteria at the time of presentation. Classification of antineutrophil cytoplasm autoantibody-associated small vessel vasculitis based on antineutrophil cytoplasm autoantibody specificity has been complicated by the finding that different ethnic groups may have very different clinical features relative to antigen specificity; for example, most patients with Wegener's granulomatosis in China have myeloperoxidase-antineutrophil cytoplasm autoantibodies rather than proteinase 3-antineutrophil cytoplasm autoantibodies.

SUMMARY

Within the past year, new classification systems for primary vasculitis have been proposed, new classification criteria have been developed, and the appropriateness of a longstanding eponym has been challenged.

Development of comprehensive disease assessment in systemic vasculitis

The systemic vasculitides are multisystem disorders with considerable mortality and morbidity and frequent relapses. In the absence of reliable serological markers, accurate clinical tools are required to assess disease activity and damage for treatment decisions, and for the performance of clinical trials. This article reviews and summarises the development and use of disease assessment tools for determining activity and damage in systemic vasculitis and reports ongoing initiatives for further development of disease assessment tools. A literature search was conducted using PubMed and reference lists for vasculitis, assessment, clinical trials, outcome and prognosis. The findings indicate that comprehensive disease assessment in vasculitis requires documentation of disease activity, chronic irreversible damage and impairment of function.

Development and validation of a consensus methodology for the classification of the ANCA-associated vasculitides and polyarteritis nodosa for epidemiological studies

BACKGROUND

The classification of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and polyarteritis nodosa (PAN) for epidemiology studies is confusing. The existing schemes such as American College of Rheumatology (ACR) criteria, Chapel Hill Consensus Conference (CHCC) definitions and Lanham criteria produce overlapping and conflicting classifications, making it difficult to compare incidence figures.

AIM

To develop a consensus method of using these criteria and definitions for epidemiological studies to permit comparison without confounding by classification.

METHODS

A stepwise algorithm was developed by consensus between a group of doctors interested in the epidemiology of vasculitis. The aim was to categorise patients with Wegener's granulomatosis, microscopic polyangiitis (MPA), Churg-Strauss syndrome (CSS) and PAN into single clinically relevant categories. The ACR and Lanham criteria for CSS, and ACR criteria for Wegener's granulomatosis were applied first, as these were considered to be the most specific. Surrogate markers for Wegener's granulomatosis were included to distinguish Wegener's granulomatosis from MPA. MPA was classified using the CHCC definition and surrogate markers for renal vasculitis. Finally, PAN was classified using the CHCC definition. The algorithm was validated by application to 20 cases from each centre and 99 from a single centre, followed by a paper case exercise.

RESULTS

A four-step algorithm was devised. It successfully categorises patients into a single classification. There was good correlation between observers in the paper case exercise (91.5%; unweighted kappa = 0.886).

CONCLUSION

The algorithm achieves its aim of reliably classifying patients into a single category. The use of the algorithm in epidemiology studies should permit comparison between geographical areas.

Cutaneous Vasculitis Update: Small Vessel Neutrophilic Vasculitis Syndromes

A broad and diverse spectrum of vasculitic syndromes exists. These syndromes affect the skin with varying levels of associated systemic manifestations, running the gamut from a self-limited, localized, cutaneous phenomenon to rapidly progressive, multiorgan disease. The majority of cases of cutaneous vasculitis will show a neutrophilic small vessel vasculitis that can be either a primary (idiopathic) disorder (eg, cutaneous leukocytoclastic angiitis) or a secondary disorder that is associated with drugs, infection (eg, streptococcal infection, viral hepatitis), or underlying disease (eg, connective tissue disease, malignancy). Biopsy is the gold standard for the diagnosis of cutaneous vasculitis and also necessary for the detection of cutaneous vascular immune complexes by direct immunofluorescence. Based on the type of vessel disrupted by inflammation (small and/or muscular), the distribution of vasculitis in the dermis and subcutis, and predominate inflammatory cell-type mediating vessel wall damage, a list of relevant differential diagnoses can be generated. This histologic information coupled with extravascular findings such as tissue eosinophilia, tissue neutrophilia, and/or granulomas, plus pathophysiologic markers such as direct immunofluorescent examination for immune complexes and serologic evaluation for antineutrophil cytoplasmic antibodies allows for more accurate diagnosis of specific vasculitic entities. Herein, we review both primary and secondary vasculitic syndromes that affect the skin and show a small vessel neutrophilic mediated vasculitis.

Cutaneous vasculitis: diagnosis and management

Vasculitis is histologically defined as inflammatory cell infiltration and destruction of blood vessels. Vasculitis is classified as primary (idiopathic, eg, cutaneous leukocytoclastic angiitis, Wegener's granulomatosis) or secondary, a manifestation of connective tissue diseases, infections, adverse drug eruptions, or a paraneoplastic phenomenon. Cutaneous vasculitis, manifested as urticaria, purpura, hemorrhagic vesicles, ulcers, nodules, livedo, infarcts, or digital gangrene, is a frequent and often significant component of many systemic vasculitic syndromes such as lupus or rheumatoid vasculitis and antineutrophil cytoplasmic antibody-associated primary vasculitic syndromes such as Churg-Strauss syndrome. In most instances, cutaneous vasculitis represents a self-limited, single-episode phenomenon, the treatment of which consists of general measures such as leg elevation, warming, avoidance of standing, cold temperatures and tight fitting clothing, and therapy with antihistamines, aspirin, or nonsteroidal anti-inflammatory drugs. More extensive therapy is indicated for symptomatic, recurrent, extensive, and persistent skin disease or coexistence of systemic disease. For mild recurrent or persistent disease, colchicine and dapsone are first-choice agents. Severe cutaneous and systemic disease requires more potent immunosuppression (prednisone plus azathioprine, methotrexate, cyclophosphamide, cyclosporine, or mycophenolate mofetil). In cases of refractory vasculitis, plasmapheresis and intravenous immunoglobulin are viable considerations. The new biologic therapies that work via cytokine blockade or lymphocyte depletion such as tumor alpha inhibitor infliximab and the anti-B-cell antibody rituximab, respectively, are showing benefit in certain settings such as Wegener's granulomatosis, antineutrophil cytoplasmic antibody-associated vasculitis, Behçet's disease, and cryoglobulinemic vasculitis.

How could we make a diagnosis of Wegener's granulomatosis?

Current classification criteria function poorly in diagnosing Wegener's granulomatosis (WG). In this study, we presented a patient with sinonasal symptoms, hematuria, and proteinuria, who had been misdiagnosed as a patient suffering from WG, but finally turned out to be a patient suffering from non-Hodgkin's T cell lymphoma. Diagnostic approach of WG was also discussed.

Classification of the vasculitides: are they clinically useful?

Several classification systems for the vasculitides have been developed over the second half of the past century. These classifications systems have been modified according to the advances made in the differentiation of these syndromes, particularly their histopathologic features (the vessel size involved) and their clinical features. Although these classifications have been widely used in the clinical setting for the diagnosis of these disorders, they were developed for research purposes. Given the common clinical and, sometimes, histopathologic features of the different vasculitides, a classification system that facilitates a diagnosis and the formulation of a therapeutic plan is still needed. The development and utilization of novel serum markers and new imaging modalities coupled with advances in the understanding of these disorders, may allow the development of a classification system for the vasculitides that will be of greater value in the clinical setting.

Wegener's granulomatosis with eosinophilia

Wegener's granulomatosis with eosinophilia both in blood and tissue samples has been rarely reported. A 25-year-old woman developed fever, granulomatous inflammation of nasal mucosa, pulmonary hemorrhage, suprascleritis, and cutaneous vasculitis. She showed eosinophilia in blood and biospy samples of skin, nasal mucosa, and lung. She was positive for proteinase 3-antineutrophil cytoplasmic antibody. She had no history of asthma. We diagnosed her as Wegener's granulomatosis with eosinophilia rather than Churg-Strauss syndrome. Her mucocutaneous and pulmonary lesions were successfully treated with high-dose corticosteroid and methotrexate, but her suprascleritis required pulsed cyclophosphamide.

Primary systemic vasculitis: clinical features and mortality

BACKGROUND

Wegener's granulomatosis (WG), Churg Strauss syndrome (CSS) and microscopic polyangiitis (MPA) are primary systemic vasculitides (PSV), the clinical features of which have been described from tertiary centres.

AIM

To provide the first clinical description of MPA from a general hospital and compare clinical features with WG and CSS.

DESIGN

Retrospective analysis of patient records.

METHODS

Records of 99 PSV patients attending a single hospital, from 1988 to 2000, were reviewed for: clinical features, date/age at diagnosis, sex, duration of illness, anti-neutrophil cytoplasmic antibodies (ANCA), treatment, comorbidity and deaths. Cases were classified using ACR, CHCC and Lanham criteria/definitions. Birmingham vasculitis activity scores (BVAS) and damage index (VDI) were calculated. Survival was assessed using Cox proportional hazards model and standardized mortality ratios (SMRs).

RESULTS

Compared to previous reports there was more ENT (29%) and respiratory (29%) but less renal (92%) involvement in MPA, and less ENT involvement in WG (81%). CSS showed high neurological (72%), cardiovascular (28%) and gastrointestinal (17%) involvement and the highest median (range) VDI (p = 0.01 vs. WG; p = 0.001 vs. MPA). BVAS1 was significantly lower in MPA than in WG [median (range) 15 (4-29) vs. 21 (6-39), (p = 0.001)] but not in CSS [20 (7-28), p = 0.08]. SMR (95%CI) for PSV was 4.8 (3.0-6.6); 5-year survival was 45.1% for MPA, 75.9% for WG and 68.1% for CSS. Age was a significant risk, but only to the same extent as in the reference population. When age was adjusted for, no other significant factor was found.

DISCUSSION

The clinical characteristics seen here are similar to those in previous series. There are difficulties in using the MPA CHCC definitions in classification. There is a high proportion of neurological involvement in CSS, causing permanent damage. MPA may have a poorer prognosis than WG or CSS.

Recent progress in the pharmacotherapy of Churg-Strauss syndrome

Churg-Strauss syndrome (CSS) is a primary systemic vasculitis occurring primarily in patients with asthma. Unlike other small vessel vasculitides, CSS is characterised by blood and tissue eosinophilia. Corticosteroids are the therapy of first choice for all stages of the disease when active vasculitis needs to be treated rapidly. In patients with severe disease and organ- or life-threatening manifestation, the addition of cyclophosphamide appears to improve the outcome and reduces the incidence of relapses. In cases with an apparently better prognosis and less severe disease, methotrexate can be given as a corticosteroid-sparing agent in order to reduce the cumulative dose of corticosteroids, which is generally high in most cases as long-term administration of corticosteroids is often inevitable in order to control asthma, even if the vasculitis is inactive. In very severe cases of CSS, cyclophosphamide and corticosteroids may be insufficient to induce remission. In these cases, anti-TNF blocking agents such as infliximab or etanercept, may be added for a limited period of time. As this intense immunosuppression increases the risk for infections, a prophylaxis with sulfamethoxazole/trimethoprim is advised. Alternatively, the administration of recombinant IFN-alpha can be a effective when given on a short-term basis in otherwise refractory cases. Whether a continuous administration of immunosuppressive agents in addition to corticosteroids can reduce the frequency of relapses in CSS who are in remission is still unknown. As relapses occur in > 25% of all patients, studies addressing the prevention of relapses in CSS are highly desirable in the future.