Effect of classification on the incidence of polyarteritis nodosa and microscopic polyangiitis

Incidence of ANCA-associated vasculitis and polyarteritis nodosa in Norfolk, UK, from 2011 to 2020

OBJECTIVE

The aim of this study was to report the annual and age-specific incidence of AAV and PAN in the adult population of Norfolk County, UK.

METHODS

Individuals newly diagnosed with AAV or PAN between 1 January 2011 and 31 December 2020 residing in the postal areas of NR1-NR30 were included. Patients were classified according to the European Medicines Agency algorithm. Population data were available from the Office of National Statistics, UK.

RESULTS

A total of 164 patients were diagnosed with AAV or PAN over 4.7 million person-years. The annual incidence (95% CI) of AAV was 34.3 (29.2, 40)/million person-years. The annual incidence (95% CI) of granulomatosis with polyangiitis, microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis was 18.9 (15.2, 23.3), 12.8 (9.7, 16.4) and 2.6 (1.3, 4.5)/million person-years, respectively. The annual incidence (95% CI) for PAN was 0.6 (0.1, 1.9)/million person-years. The age-specific incidence of granulomatosis with polyangiitis and microscopic polyangiitis rose with each decade of life and was highest in the 8th decade for granulomatosis with polyangiitis [53.2 (95% CI 36.2, 75.6) per million] and in the 9th decade for microscopic polyangiitis [48.4 (95% CI 27.1, 79.8) per million].

CONCLUSION

The incidence of AAV, specifically that of granulomatosis with polyangiitis and of microscopic polyangiitis, is slowly rising over time. It is most notable among the elderly population, among whom the incidence rates for granulomatosis with polyangiitis and microscopic polyangiitis peak. There may be a 4-year incidence cycle, which needs confirmation in a longer study.

Classification and epidemiology of vasculitis: Emerging concepts

The recent publication of the American College of Rheumatology (ACR)-European Alliance of Associations for Rheumatology (EULAR) classification criteria for large vessel vasculitis and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) has provided modern criteria for the classification of these conditions, which incorporate contemporary methods of investigation and diagnosis. Further validation is required in independent cohorts, especially from populations that were not well represented in the development cohort. Studies of the occurrence of large vessel vasculitis report that Takayasu arteritis is a rare disease in most populations, and giant cell arteritis is the most common vasculitis in older populations. The incidence of AAV appears to have plateaued, but the prevalence is increasing as a result of lower mortality. The new classification criteria may affect the reported incidence and prevalence, and studies will be needed to confirm this. The impact of COVID-19 on the occurrence of the vasculitides is not completely known, but there is evidence of reduced occurrence of Kawasaki disease and IgA-associated vasculitis following lockdowns with reduced transmission of possible trigger infectious agents.

Systematic Review and Metaanalysis of Worldwide Incidence and Prevalence of Antineutrophil Cytoplasmic Antibody (ANCA) Associated Vasculitis

Objective: In this study, we aimed to evaluate the worldwide incidence and prevalence of ANCA-associated vasculitis (AAV). Methods: A systematic search of Medline and Embase was conducted until June 2020 for studies that analyzed the incidence and prevalence of patients aged >16 years diagnosed with AAV in different geographical areas. A meta-analysis was undertaken to estimate the pooled incidence per million person-years and prevalence per million persons in AAV overall and for each subtype of AAV: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). The 95% confidence interval (CI) and I2 for heterogeneity were calculated. Results: The meta-analysis included 25 studies that met the inclusion criteria and covered a total of 4547 patients with AAV. Frequency increased over time. The global pooled incidence (95% CI) was 17.2 per million person-years (13.3−21.6) and the global pooled prevalence (95% CI) was 198.0 per million persons (187.0−210.0). The pooled incidence per million person-years for each AAV subtype varied from highest to lowest, as follows: GPA, 9.0; MPA, 5.9; and EGPA, 1.7. The individual pooled prevalence per million persons was, as follows: GPA, 96.8; MPA, 39.2; and EGPA, 15.6. AAV was more predominant in the northern hemisphere. By continent, a higher incidence in America and pooled prevalence of AAV was observed in America and Europe. Conclusion: The pooled incidence and prevalence of AAV seem to be increasing over time and are higher in the case of GPA. AAV was generally more frequent (incidence and prevalence) in the northern hemisphere.

Efficacy of plasma exchange therapy for diffuse alveolar hemorrhage in patients with microscopic polyangiitis

INTRODUCTION

Diffuse alveolar hemorrhage (DAH) is associated with high mortality. We examined the efficacy of plasma exchange (PE) therapy for reducing mortality in patients with patients with microscopic polyangiitis (MPA) and DAH.

METHODS

In this 52-week, non-randomized, open-label, one-arm, historical control, double-center controlled trial, four patients with MPA and DAH admitted to Juntendo University Hospital or Juntendo Koto Geriatric Medical Center between 2018 and 2021 were enrolled. Sixteen patients with MPA and DAH admitted to the two centers between 1998 and 2018 who did not receive PE were included as the historical control group. The primary outcome was the 52-weekurvival rate of patients in each treatment arm.

RESULTS

The 52-week survival rate of patients in the PE group (n=4) was higher than that of the historical control group (n=16) (100% vs. 13%, P=.04).

CONCLUSION

We found that PE may be efficacious for reducing mortality in patients with MPA and DAH. This article is protected by copyright. All rights reserved.

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.

Insidious coronary artery disease in a young patient with polyarteritis nodosa: a case report and literature review

Background

Polyarteritis nodosa (PAN) is a relatively rare systemic necrotizing vasculitis that typically affects medium-sized arteries. Although myocardial ischemia may occur due to involvement of the coronary arteries, overt myocardial infarction is uncommon.

Case presentation

A 22-year-old Chinese man experiencing chest pain for 7 months was admitted to our hospital. Consistently, the pain tended to last for a few minutes and then spontaneously subside. He had 7-year history of “stable” PAN. Coronary angiography revealed slight plaque infiltration of the left main coronary artery; however occlusion of all the three major coronary arteries with multiple aneurysms. A stent was implanted into the obtuse margin branch artery which was 95% stenosis, and then the chest pain was alleviated. Considering that the occlusion of coronary arteries was due to insidious vasculitis, prednisone 50 mg/day and methotrexate 15 mg/week were reinitiated, in combination with anti-angina medications.

Conclusions

We report a young patient with insidious occlusion of three main coronary arteries under the circumstance of stable PAN for 7 years, suggesting the necessity of assessing the heart, in spite of normal acute phase reactants. The appropriate screening strategy needs to be studied.

Plasma Exchange Therapy to Reduce Mortality in Japanese Patients With Diffuse Alveolar Hemorrhage and Microscopic Polyangiitis

Diffuse alveolar hemorrhage (DAH) is well known as a serious complication of microscopic polyangiitis (MPA). We examined the effectiveness of plasma exchange (PLEX) therapy to reduce mortality in Japanese DAH patients with MPA. This retrospective, double-center, observational cohort study included 20 DAH patients with MPA who were admitted to Juntendo University Hospital or Juntendo Koto Geriatric Medical Center between April 1998 and March 2018. The primary outcome was non-disease-specific mortality. The 1-year survival rate of patients with PLEX therapy (N = 4) was higher than that of patients with conventional therapy (N = 16, 75% and 13%, respectively, P = 0.037). Higher values of the 1996 Five-Factor Score (FFS) and 2009 FFS were associated with increased mortality, with hazard ratios of 2.29 (P = 0.040) and 2.41 (P = 0.043), respectively, by Cox univariate analysis. We investigated PLEX therapy for reducing mortality in DAH patients with MPA, and the 1996 FFS and 2009 FFS were both independent prognostic factors.

Association of five-factor score with the mortality in Japanese patients with polyarteritis nodosa

AIM

To determine mortality and its predictive factors in Japanese patients with polyarteritis nodosa (PAN).

METHODS

This retrospective single-center study determined the mortality of 18 patients with PAN who were admitted to Juntendo University Hospital from 1994 to 2016. The variables at baseline, including patient demographics, clinical characteristics, and treatment, were analyzed for their association with mortality.

RESULTS

The median age of onset was 57.0 years. The 1-year survival rate was 100% (16/16) and the 5-year survival rate was 80.0% (8/10). The relationship between mortality, as defined by the survival rate and each variable was evaluated by Cox univariate analysis. A higher 2009 five-factor score (FFS) was associated with increased mortality, with a hazard ratio of 2.34 (p = .04). Analysis of the secondary outcome of relapse-free survival time revealed an association with rapid progressive renal failure, Birmingham Vasculitis Activity Score (BVAS), the 1996 FFS, and the 2009 FFS, with hazard ratios of 7.28 (p = .048), 1.26 (p = .02), 2.32 (p = .03), and 1.82 (p = .04), respectively.

CONCLUSION

We investigated mortality, relapse-free survival, and their predictive factors in Japanese patients with PAN. The BVAS and the 1996 FFS at diagnosis may be prognostic factors for relapse-free survival, and the 2009 FFS at diagnosis may be a prognostic factor for both mortality and relapse-free survival.

Comparing Presenting Clinical Features in 48 Children With Microscopic Polyangiitis to 183 Children Who Have Granulomatosis With Polyangiitis (Wegener's): An ARChiVe Cohort Study

OBJECTIVE

To uniquely classify children with microscopic polyangiitis (MPA), to describe their demographic characteristics, presenting clinical features, and initial treatments in comparison to patients with granulomatosis with polyangiitis (Wegener's) (GPA).

METHODS

The European Medicines Agency (EMA) classification algorithm was applied by computation to categorical data from patients recruited to the ARChiVe (A Registry for Childhood Vasculitis: e-entry) cohort, with the data censored to November 2015. The EMA algorithm was used to uniquely distinguish children with MPA from children with GPA, whose diagnoses had been classified according to both adult- and pediatric-specific criteria. Descriptive statistics were used for comparisons.

RESULTS

In total, 231 of 440 patients (64% female) fulfilled the classification criteria for either MPA (n = 48) or GPA (n = 183). The median time to diagnosis was 1.6 months in the MPA group and 2.1 months in the GPA group (ranging to 39 and 73 months, respectively). Patients with MPA were significantly younger than those with GPA (median age 11 years versus 14 years). Constitutional features were equally common between the groups. In patients with MPA compared to those with GPA, pulmonary manifestations were less frequent (44% versus 74%) and less severe (primarily, hemorrhage, requirement for supplemental oxygen, and pulmonary failure). Renal pathologic features were frequently found in both groups (75% of patients with MPA versus 83% of patients with GPA) but tended toward greater severity in those with MPA (primarily, nephrotic-range proteinuria, requirement for dialysis, and end-stage renal disease). Airway/eye involvement was absent among patients with MPA, because these GPA-defining features preclude a diagnosis of MPA within the EMA algorithm. Similar proportions of patients with MPA and those with GPA received combination therapy with corticosteroids plus cyclophosphamide (69% and 78%, respectively) or both drugs in combination with plasmapheresis (19% and 22%, respectively). Other treatments administered, ranging in decreasing frequency from 13% to 3%, were rituximab, methotrexate, azathioprine, and mycophenolate mofetil.

CONCLUSION

Younger age at disease onset and, perhaps, both gastrointestinal manifestations and more severe kidney disease seem to characterize the clinical profile in children with MPA compared to those with GPA. Delay in diagnosis suggests that recognition of these systemic vasculitides is suboptimal. Compared with adults, initial treatment regimens in children were comparable, but the complete reversal of female-to-male disease prevalence ratios is a provocative finding.

The Incidence of Primary Systemic Vasculitis in Jerusalem: A 20-year Hospital-based Retrospective Study

Objective.

The incidence of primary systemic vasculitides varies among different geographic regions and ethnic origins. The aim of this study was to examine the incidence rates of vasculitides in the Jerusalem Jewish population, and to examine possible trends in incidence rates over a 20-year period.

Methods.

The clinical databases of inpatients at the 2 medical centers in Jerusalem were searched for patients with vasculitis diagnosed between 1990–2009. Individual records were then reviewed by one of the authors. The significance of trends in incidence rates throughout the study period was evaluated by Pearson correlation coefficient.

Results.

The average annual incidence rate of polyarteritis nodosa was 3.6/million adults (95% CI 1.6–4.7). Incidence rates did not change significantly during this period (r = 0.39, p = 0.088). The incidence of granulomatosis with polyangiitis (GPA) was 4.1 (2.2–5.9) for the whole period, during which it increased significantly (r = 0.53, p < 0.05). The incidence of microscopic polyangiitis (MPA) was lower: 2.3 (1.2–3.5)/million. It also increased significantly (r = 0.55, p < 0.05). The incidence of eosinophilic granulomatosis with polyangiitis was 1.2 (0.4–1.9), which remained stable throughout the study period. The incidence of Takayasu arteritis was 2.1/million (95% CI 1.2–2.9), and it also remained stable. Giant cell arteritis (GCA) incidence was 8.1 (5.7–10.6)/100,000 population aged 50 years or older. In sharp contrast with other vasculitides, its incidence decreased significantly throughout the study period (r = −0.61, p < 0.01).

Conclusion.

The incidence rates of vasculitides in the Jewish population of Jerusalem are in the lower range of global incidence rates. While GPA and MPA incidence are increasing, GCA incidence is decreasing.

PAN's labyrinth: a multidisciplinary delayed diagnosis and patient's perspective

Polyarteritis nodosa (PAN) is a rare, severe form of vasculitis affecting medium-sized vessels. It manifests as a multisystem syndrome, and may be associated with hepatitis B virus-associated PAN (HBV-PAN) although the incidence of this is declining with better vaccination strategies and awareness of bloodborne virus screening. We report a case in which a patient displayed many classical features of the disease, occurring separately over a period of months and leading to contact with various medical specialties. Managing each symptom in isolation led to a number of misdiagnoses (including testicular cancer) and the patient experienced considerable psychological stress and morbidity as a result. The case was complicated by acute pancreatitis developing after an initial treatment response. This may have been iatrogenic (as a consequence of either entecavir or steroids) or secondary to PAN. For our patient, this led to a protracted clinical course but eventual complete resolution of both pathologies.

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.

Coronary artery bypass grafting in a patient with polyarteritis nodosa presenting with acute myocardial infarction and multiple coronary aneurysms

Polyarteritis nodosa (PAN) is a necrotizing form of vasculitis that affects small- and medium- sized vessels. Cases of ischemic heart disease involving coronary aneurysms in patients with PAN have been reported previously, but there have only been a few reports of coronary artery surgery for PAN-related coronary disease. A 46-year-old female with a history of PAN arrived at our emergency room due to cardiopulmonary arrest. After cardiopulmonary resuscitation, emergent coronary angiography was performed, because an electrocardiogram demonstrated ST segment elevation in leads V1 to V5. Coronary angiography revealed occlusion of the proximal right coronary artery and left anterior descending coronary artery as well as multiple coronary aneurysms. We performed emergent two-vessel coronary artery bypass grafting (the left anterior descending coronary artery and posterolateral branch of the circumflex system were treated with grafts from the left internal mammary artery and saphenous vein graft, respectively) under percutaneous cardiopulmonary support without cardiac arrest. The patient's postoperative course was uneventful, and postoperative coronary angiography revealed that the bypass grafts were patent. A review of the literature and a discussion of this case are also presented.

An unusual presentation of classic idiopathic polyarteritis nodosa as acute interstitial nephritis

In the medical literature, there have been few reported cases of classic Polyarteritis Nodosa (cPAN) presenting with acute renal failure (ARF) and, unlike microscopic polyangiitis (MPA), no documentation to our knowledge of cPAN with clinical presentation similar to acute interstitial nephritis. We describe a case of ARF and a clinical picture suggestive of acute interstitial nephritis (AIN). However, renal biopsy of this patient showed acute necrotizing intrarenal vasculitis, suggestive of cPAN. Although no guidelines exist for the most appropriate therapy for patients presenting in this fashion, combination therapy with cyclophosphamide and steroids, in our patient, resulted in clinical improvement and resolution of dialysis-dependent renal failure. These findings suggest the potential for good prognosis in patients with cPAN who present with a presumed diagnosis of AIN and dialysis-dependent ARF.

[Approach and challenges in primary vasculitidies]

The primary systemic vasculitidies (PSV) comprise an heterogeneous group of complex clinical entities with a common substrate: inflammation and necrosis of blood vessels. The inflammatory process involves vessels of any caliber. The location and the different size of the affected vessels, the severity of vascular damage and the different histopathological patterns which may predominate are the basic characteristics that define the different vasculitic syndromes and enable individualization. The description and progress in the knowledge of the primary vasculitidies have evolved considerably in recent decades, allowing for a better resolution of the complex problems placed by these patients. This review aims to provide a view on the practical approach to these diseases and their challenge. It focuses on ANCA associated vasculitidies (AAV) because this subgroup has the only proven biomarker and is the most common in our area. Also, multiorganic involvement is frequent. Some notes regarding other PSV are made.

Nomenclature and classification of vasculitis - update on the ACR/EULAR diagnosis and classification of vasculitis study (DCVAS)

Classification of vasculitis remains unsatisfactory. This is largely because the pathogenetic mechanisms of this family of related disorders have not been fully understood. Existing classification criteria are useful but limited. This has become more apparent with the advent of more effective and more specific therapies. A rational basis for classification could significantly improve our approach to treatment. The development of diagnostic criteria in vasculitis is an even greater challenge but may ultimately provide more useful for the non-specialist clinician. International efforts are underway to provide more effective classification and diagnostic criteria.

Microscopic polyangiitis

In 1923, Friedrich Wohlwill described two patients with a "microscopic form of periarteritis nodosa," which was distinct from the classical form. This disease, now known as microscopic polyangiitis (MPA), is a primary systemic vasculitis characterized by inflammation of the small-caliber blood vessels and the presence of circulating antineutrophil cytoplasmic antibodies. Typically, microscopic polyangiitis presents with glomerulonephritis and pulmonary capillaritis, although involvement of the skin, nerves, and gastrointestinal tract is not uncommon. Treatment of MPA generally requires use of a cytotoxic agent (such as cyclophosphamide) in addition to high-dose glucocorticoids. Recent research has focused on identifying alternate treatment strategies that minimize or eliminate exposure to cytotoxic agents. This article reviews the history, pathogenesis, clinical manifestations, and treatment of MPA.

Epidemiology of ANCA-associated vasculitis

The epidemiology of the antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV), comprising Wegener's granulomatosis, microscopic polyangiitis, and Churg-Strauss syndrome, poses considerable challenges to epidemiologists. These challenges include the difficulty of defining a case with a lack of clear distinction between the different disorders, case capture, and case ascertainment. The AAV are rare and therefore a large population is required to determine the incidence and prevalence, and this poses questions of feasibility. Despite these difficulties a considerable body of data on the epidemiology of the AAV has been built in the past 20 years with an interesting age, geographic, and ethnic tropism gradually being revealed. Most of the data come from White populations of European descent, and the overall annual incidence is estimated at approximately 10-20/million with a peak age of onset in those aged 65 to 74 years.

Gastrointestinal involvement in polyarteritis nodosa

Polyarteritis nodosa (PAN) is a necrotizing, focal segmental vasculitis that affects predominantly medium-sized arteries in many different organ systems. It is associated with hepatitis B virus (HBV) in about 7% of cases, a decline from about 30% before the mandatory testing of blood products and the widespread vaccination programs. HBV PAN is an early postinfectious process. The hepatitis is silent in most cases, with mild transaminase level increases in 50% of patients. Gastrointestinal involvement occurs in 14% to 65% of patients with PAN. Postprandial abdominal pain from ischemia is the most common symptom. When transmural ischemia develops, there may be necrosis of the bowel wall with perforation, associated with a poor prognosis. Liver involvement occurs in 16% to 56% of patients, although clinical manifestations related to liver disease are quite rare. Acalculous gangrenous cholecystitis may develop owing to arteritis involving the wall of the gallbladder. Microaneurysms on arteriography or computed tomography angiography are characteristic of PAN, but are seen in other conditions. Tissue biopsy may confirm the diagnosis, although involvement is segmental. Corticosteroids are used for non-HBV PAN with cyclophosphamide added for severe disease. For PAN related to HBV, a 2-week course of corticosteroids is begun, with plasma exchanges and an antiviral agent. Corticosteroids and cyclophosphamide have improved patient outcome so that the 1-year survival rate is now about 85%.

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.

Cutaneous manifestations of vasculitis

OBJECTIVES

To discuss the clinical features, diagnostic evaluation, and treatment options for cutaneous vasculitis.

METHODS

The literature in the PubMed database was reviewed regarding the presentation, pathophysiology, clinical workup, and treatment of cutaneous vasculitis.

RESULTS

Available classification criteria of vasculitis are based on histopathologic criteria or clinicohistologic features. These have been designed more for research purposes than for clinical application. Skin findings such as palpable purpura, nodules, urticaria, ulcers, and infarction are clues to the presence of vasculitis. Pathologic findings of fibrinoid necrosis, infiltration by neutrophils or lymphocytes, and deposition of complement and immunoglobulin may be helpful in reaching a specific diagnosis. However, there is considerable overlap across different conditions.

CONCLUSIONS

The correct diagnosis of cutaneous manifestations of vasculitis requires an understanding of vasculitis classification, recognition of specific clinical patterns, and the ability to interpret histopathologic data.

Vasculitis in the geriatric population

Vasculitis represents an uncommon but important group of disease entities that may affect older patients. The most common vasculitic disease in humans in giant cell arteritis, a disease process seen almost exclusively in patients older than 50 years in age. Vasculitic disease in geriatric patients presents unique challenges with regard to diagnosis and treatment. A thorough understanding of the vasculitic disease entities that may affect older patients as well as their diagnosis and management is essential in minimizing disease and treatment-related morbidity and mortality.

Cutaneous Vasculitis Update: Neutrophilic Muscular Vessel and Eosinophilic, Granulomatous, and Lymphocytic Vasculitis Syndromes

Most biopsies of cutaneous vasculitis will exhibit a small vessel neutrophilic vasculitis [leukocytoclastic vasculitis (LCV)] that is associated with immune complexes on direct immunofluorescence examination or, less commonly, antineutrophilic cytoplasmic antibodies (ANCA) by indirect immunofluorescence testing. Is in uncommon for skin biopsy to reveal solely a neutrophilic arteritis signifying the presence of cutaneous polyarteritis nodosa or, if accompanied by significant lobular panniculitis, nodular vasculitis/erythema induratum. In other cases, cutaneous vascular damage (fibrinoid necrosis, muscular vessel wall disruption, or endarteritis obliterans) will be mediated by a nonneutrophilic inflammatory infiltrate. Eosinophilic vasculitis can be a primary (idiopathic) process that overlaps with hypereosinophilic syndrome, or it can be a secondary vasculitis associated with connective tissue disease or parasite infestation. Authentic cutaneous granulomatous vasculitis (versus vasculitis with extravascular granulomas) can represent a cutaneous manifestation of giant cell arteritis, an eruption secondary to systemic disease such as Crohn's disease or sarcoidosis, or a localized disorder, often a post-herpes zoster (HZ) phenomenon. Lymphocytic vasculitis is a histologic reaction pattern that correlates with broad clinical differential diagnosis, which includes connective tissue disease - mostly systemic lupus erythematosus (SLE), endothelial infection by Rickettsia and viruses, idiopathic lichenoid dermatoses such as perniosis or ulcerative necrotic Mucha-Habermann disease, and angiocentric cutaneous T-cell lymphomas. Skin biopsy extending into the subcutis, identifying the dominant inflammatory cell and caliber of vessels affected, extravascular histologic clues such as presence of lichenoid dermatitis or panniculitis, and correlation with clinical data allows for accurate diagnosis of these uncommon vasculitic entities.

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.

Cutaneous Vasculitis Update: Diagnostic Criteria, Classification, Epidemiology, Etiology, Pathogenesis, Evaluation and Prognosis

Vasculitis, inflammation of the vessel wall, can result in mural destruction with hemorrhage, aneurysm formation, and infarction, or intimal-medial hyperplasia and subsequent stenosis leading to tissue ischemia. The skin, in part due to its large vascular bed, exposure to cold temperatures, and frequent presence of stasis, is involved in many distinct as well as un-named vasculitic syndromes that vary from localized and self-limited to generalized and life-threatening with multi-organ disease. To exclude mimics of vasculitis, diagnosis of cutaneous vasculitis requires biopsy confirmation where its acute signs (fibrinoid necrosis), chronic signs (endarteritis obliterans), or past signs (acellular scar of healed arteritis) must be recognized and presence of extravascular findings such as patterned fibrosis or collagenolytic granulomas noted. Although vasculitis can be classified by etiology, many cases have no identifiable cause, and a single etiologic agent can elicit several distinct clinicopathologic expressions of vasculitis. Therefore, the classification of cutaneous vasculitis is best approached morphologically by determining vessel size and principal inflammatory response. These histologic patterns roughly correlate with pathogenic mechanisms that, when coupled with direct immunofluorescent examination, anti-neutrophil cytoplasmic antibody (ANCA) status, and findings from work-up for systemic disease, allow for specific diagnosis, and ultimately, more effective therapy. Herein, we review cutaneous vasculitis focusing on diagnostic criteria, classification, epidemiology, etiology, pathogenesis, and evaluation of the cutaneous vasculitis patient.

Polyarteritis nodosa revisited

Polyarteritis nodosa (PAN), the prototype of systemic vasculitis, is a rare condition characterized by necrotizing inflammation of medium-sized or small arteries without glomerulonephritis or vasculitis in arterioles, capillaries, or venules. Signs and symptoms of this disease are primarily attributable to diffuse vascular inflammation and ischemia of affected organs. Virtually any organ with the exception of the lungs may be affected, with peripheral neuropathy and symptoms from osteoarticular, renal artery, and gastrointestinal tract involvement being the most frequent clinical manifestations. A clear distinction between limited versus systemic disease and idiopathic versus hepatitis B related PAN should be done because there are differences in the implicated pathogenetic mechanisms, their treatment, and prognosis. Currently, corticosteroids plus cyclophosphamide is the standard of care for idiopathic PAN, in particular for patients with adverse prognostic factors (more severe disease), in whom this combination prolonged survival. In contrast for hepatitis B related PAN treatment consists of schemes that include plasmapheresis and antiviral agents.

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.

The Clinical Spectrum of Primary Renal Vasculitis

BACKGROUND AND OBJECTIVES

The vasculitides are potentially severe and often difficult to diagnose syndromes. Many forms of vasculitis may involve the kidneys. This review will focus on the clinical and histopathological aspects of renal involvement in the systemic vasculitides.

METHODS

We searched the MEDLINE database using as key terms the MeSH terms and textwords for different forms of vasculitis and for renal involvement, creating a database of more than 2200 relevant references.

RESULTS

The frequency of renal involvement in vasculitis varies among different syndromes. It is more frequent in Wegener's granulomatosis and microscopic polyarteritis, while it is uncommon to rare in other forms of vasculitis such as Behçet's disease and relapsing polychondritis. The vessels affected include the renal artery in Takayasu arteritis, medium-size renal parenchymal artery in classic polyarteritis nodosa, and glomerular involvement in Wegener's granulomatosis and microscopic polyarteritis. The clinical expression of renal vasculitis depends on the size of the affected vessels and includes renovascular hypertension, isolated nonnephrotic proteinuria, interstitial nephritis, and glomerulonephritis, which can be rapidly progressive. Diagnosis is established by a combination of history, clinical manifestations, laboratory findings (eg, urine sediment, urine protein, antineutrophil cytoplasmic antibodies), imaging techniques (renal angiography, especially when there is a suspicion of medium-to-large vessel disease, and chest radiograph), and finally, renal biopsy. Prognosis varies from unfavorable in the rapidly progressive glomerulonephritis of microscopic polyarteritis, which can lead to renal failure, chronic dialysis, and renal transplantation, to benign, as in the case of Henoch Schonlein purpura, in which the majority of patients recover.

CONCLUSIONS

The manifestations and prognosis of renal vasculitis range widely. Renal involvement greatly influences prognosis and dictates the need for early and prompt immunosuppressive therapy. Thus, the clinician should be alert for the timely diagnosis and treatment of renal vasculitis.

Vasculitis in the Geriatric Population

Vasculitis represents an uncommon but important group of disease entities that may affect older patients. The most common systemic vasculitic disease in humans is giant cell arteritis, a disease process seen almost exclusively in patients over the age of 50. Vasculitic disease in geriatric patients presents unique challenges with regard to diagnosis and treatment. A thorough understanding of the vasculitic disease entities that may affect older patients as well as their diagnosis and management is essential in minimizing disease and treatment related morbidity and mortality.

Spontaneous fusion between cancer cells and endothelial cells

Endothelial cells line the inside of blood and lymphatic vessels, and cancer cells must cross this barrier, first to gain access to the circulation, and, second, to exit and metastasize. How this occurs is incompletely understood. We now demonstrate that human cancer cells are able to fuse with endothelial cells to form hybrid cells displaying proteins and chromosomal markers characteristic of both parent cells. The hybrid cells are viable and capable of undergoing mitosis. Fusions between cancer cells and endothelial cells were shown to occur both in vitro, in co-cultures of human breast cancer cells and endothelial cells, and in vivo, following intravascular dissemination of human breast cancer cells in nude mice. These observations demonstrate a new type of cancer-endothelial cell interaction that may be of fundamental importance to the process of metastasis.

Prevalences of polyarteritis nodosa, microscopic polyangiitis, Wegener's granulomatosis, and Churg-Strauss syndrome in a French urban multiethnic population in 2000: a capture-recapture estimate

OBJECTIVE

To estimate the prevalences of polyarteritis nodosa (PAN), microscopic polyangiitis (MPA), Wegener's granulomatosis (WG), and Churg-Strauss syndrome (CSS).

METHODS

Cases were collected in Seine-St. Denis County, a northeastern suburb of Paris, which has 1,093,515 adults (> or =15 years), 28% of whom are of non-European ancestry. The study period encompassed the entire calendar year 2000. Cases were identified by general practitioners, the departments of all the public hospitals and 2 large private clinics, and the National Health Insurance System. The Chapel Hill nomenclature was used to define MPA, and American College of Rheumatology criteria to define WG and CSS; PAN was diagnosed based on clinical laboratory, histological and/or angiographic findings. Three-source capture-recapture analysis was performed to correct for incomplete case ascertainment.

RESULTS

A total of 75 cases were retained and capture-recapture analysis estimated that 23.8 cases had been missed by any 1 of the 3 sources. Accordingly, prevalences per 1,000,000 adults (95% confidence interval [95% CI]) were estimated to be 30.7 (95% CI 21-40) for PAN, 25.1 (95% CI 16-34) for MPA, 23.7 (95% CI 16-31) for WG, and 10.7 (95% CI 5-17) for CSS. The overall prevalence was 2.0 times higher for subjects of European ancestry than for non-Europeans (P = 0.01).

CONCLUSIONS

This study provides the first prevalence estimates for these 4 vasculitides for a multiethnic, urban population. The significantly higher prevalence observed for Europeans may infer a genetic susceptibility of Caucasians. Compared with previous estimates based mostly on rural populations, the higher frequency of PAN and the lower frequency of WG might suggest specific environmental etiologic factors.

[Systemic necrotizing vasculitides: classifications and therapeutic strategies]

OBJECTIVES

The knowledge of systemic necrotizing vasculitides improved since new classifications have been established along with a better understanding of pathogenesis of the diseases. The major vasculitides are described herein.

CURRENT KNOWLEDGE AND KEY POINTS

Pathogenesis plays now a major role for classifying diseases and influences the diagnostic strategies. The prospective therapeutic trials established by French and European groups are largely based on our better knowledge of the diseases.

FUTURE PROSPECTS AND PROJECTS

Despite the good results obtained with and demonstrated in prospective trials, the vasculitides remain severe and deserve new studies testing new drugs but also strategies based on prognostic factors and scores which should play a major role in treatments decision.

Cutaneous vasculitis

Vasculitis can range in severity from a self-limited single-organ disorder to a life-threatening disease with the prospect of multiple-organ failure. This condition presents many challenges to the physician, including classification and diagnosis, appropriate laboratory workup, treatment, and the need for careful follow-up. The physician must not only be able to recognize vasculitis but also be able to provide a specific diagnosis (if possible) as well as recognize and treat any underlying etiologic condition. Most diagnostic criteria are based on the size of vessel involvement, which often correlates with specific dermatologic findings. This may allow the dermatologist to provide an initial diagnosis and direct the medical evaluation. This article reviews the classification and diagnosis of cutaneous vasculitic syndromes and current treatment options; it also presents a comprehensive approach to diagnosing and treating the patient with suspected cutaneous vasculitis. (J Am Acad Dermatol 2003;48:311-40.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be familiar with the classification and clinical features of the various forms of cutaneous vasculitis. They should also have a rational approach to diagnosing and treating a patient with vasculitis.

Systemic vasculitides

The vasculitides are a heterogeneous group of diseases that are characterized by blood vessel inflammation and necrosis. They have a wide spectrum of manifestations due to the involvement of arteries and other vessels of various sizes and locations. Classification criteria are useful in improving our understanding of the epidemiology of these conditions but they are not diagnostic criteria. In recent years a progressive increase in incidence has been reported. Both giant cell arteritis and Wegener's granulomatosis are more common in the Northern hemisphere. Environmental factors have been implicated in the pathogenesis of these syndromes. Recent studies in patients with large and small-sized vasculitides support a genetic influence in disease susceptibility. They have confirmed the association of giant cell arteritis and Henoch-Schönlein purpura with HLA-DRB1 alleles. Moreover, the polymorphisms of other genes, such as interleukin-1 receptor antagonist, seem to be implicated in disease severity in patients with cutaneous vasculitis.

Systemic Vasculitis

The systemic vasculitides are a heterogeneous group of disorders characterized by inflammation of blood vessel walls. They can be classified according to the size of vessel affected and also into primary de novo vasculitides and secondary to other disease processes. Treatments differ and overlap depending on the type of vasculitis. It is therefore important to make the correct diagnosis and treat appropriately to achieve remission as there is a substantial mortality implication.

Historical perspective of vasculitis: polyarteritis nodosa and microscopic polyangiitis

The original and early case reports of vasculitis provide a historical context and foundation for understanding current concepts of these diseases. These early case reports are valuable as reference points for the current efforts in diagnosing, treating, and classifying vasculitis. In addition, they emphasize the importance of careful clinical observation in these efforts and the essential nature of medical science. Polyarteritis nodosa was the first noninfectious vasculitis to be described and studied in detail. Research on this group of vasculitides has been the cornerstone for understanding the pathophysiology of other forms of idiopathic vasculitis. Historically, most forms of vasculitis described subsequently have been characterized and classified on the basis of features similar to or distinct from polyarteritis.

Polyarteritis nodosa and microscopic polyangiitis: etiologic and diagnostic considerations

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis of medium-sized vessels with clinical manifestations resulting from ischemia and infarction of affected tissues and organs. Although the cause of most cases of PAN and the related disorder microscopic polyangiitis (MPA) remains largely unknown, there has been significant progress in understanding the pathogenesis of vascular inflammation. The diagnostic approach to PAN and MPA should be individualized and based on specific organ involvement. Because no test or clinical finding reliably indicates the presence or absence of PAN or MPA, diagnosis requires integration of clinical findings, angiography, and biopsy data.

Epidemiology of the vasculitides

In summary, systemic vasculitides constitute a heterogeneous group of overlapping diseases that are somewhat more common than previously considered. Although the causes of vasculitis are largely unknown, epidemiologic studies have implicated geographic, genetic, and environmental factors. Ethnicity, various genes such as those of the MHC, gender, and environmental factors seem to account for the different incidence rates of these syndromes. GCA is the most common vasculitis in elderly people from Western countries. Small-sized cutaneous vasculitides, particularly HSP in children and HV in adults, are also common diseases. Increased physician awareness and the routine use of ANCA tests may contribute to an increase in the recognition of conditions such as WG and MPA.

Introduction to, and classification of, the systemic vasculitides

This overview serves as an introduction to the systemic vasculitides, which are a group of heterogeneous disorders sharing a common pathophysiological mechanism leading to blood vessel inflammation and tissue necrosis. Our lack of understanding of the aetiology for most forms of vasculitis has resulted in the development of a classification system, which is primarily based on vessel size. Such a system assists in the grouping together of similar conditions for the purposes of multi-centre studies. Difficulties arise in classification of the vasculitides due to considerable overlap of clinico-pathological features; for example, microscopic polyangiitis (MPA), Wegener's granulomatosis (WG) and Churg-Strauss syndrome (CSS) may all cause the identical renal lesion of necrotizing glomerulonephritis. The rationale for treatment often depends on the type of vasculitis and on the extent of organ involvement. Treatment may be similar for different types of disease. The lack of validated diagnostic criteria has, however, resulted in the application of classification criteria in their place, and has highlighted the limited usefulness of classification criteria in clinical practice. Classification systems should assist in the determination of therapy and prediction of outcomes, but have many limitations, which are discussed further in this review.