Polyarteritis nodosa when applying the Chapel Hill nomenclature--a descriptive study on ten patients

The clinical characteristics and treatment outcomes of patients with systemic polyarteritis nodosa: a single-centre study from India

OBJECTIVE

To describe the clinical profile and compare the long-term outcomes of patients with systemic polyarteritis nodosa (S-PAN) treated with various treatment regimens at our centre in the last two decades.

METHODS

Data regarding clinical presentation, treatment allocation, relapses and outcomes of patients fulfilling American College of Rheumatology (ACR) 1990 criteria for PAN in the last two decades were recorded from electronic medical records. Relapse-free survival and predictors were analysed using Kaplan-Meier survival statistics and regression analysis.

RESULTS

Altogether, 53 patients, including two with hepatitis B infection, were included. Cutaneous lesions and peripheral neuropathy were the commonest manifestations. Most patients (64.2%) presented with a five-factor score (FFS) of 0. Disease-attributable hypertension and peripheral gangrene were the most common manifestations of severe disease. During a median follow-up period of 53.5 months in 49 patients who had a follow up, 43 (87.8%) attained complete response while 3 (6.1%) had a partial response. Among 46 patients who had follow up of more than 3 months, 19 (41.3%) patients relapsed at a median duration of 82 (interquartile range 36.3-127.7) months. The relapse-free survival in patients who received induction with mycophenolate (n = 26) was comparable to that with cyclophosphamide (n = 21) [adjusted hazard ratio (HR): 0.68]. Smoking history was an independent predictor of relapse (HR = 6.28, P = 0.013) while age was protective (HR = 0.94, P = 0.015). Overall, fatality was observed in 5 (10%) patients. FFS and BVAS at 3 months were among the predictors of mortality.

CONCLUSION

In our cohort of S-PAN, relapses were observed in 41.3% of patients. Mycophenolate was similar to cyclophosphamide in maintaining relapse-free survival. Only 10% fatality was recorded. FFS and BVAS at 3 months were predictors of mortality.

Pericarditis of Polyarteritis Nodosa

Polyarteritis nodosa (PAN) is a rare systemic vasculitis characterised by necrotising inflammation of medium-sized arteries. PAN can affect patients of any age, gender, or ethnic background. Its highest incidence is in the fifth-sixth decade of life, with a slight male-to-female predilection. PAN can be idiopathic or secondary to a multitude of systemic conditions, such as infection, haematological malignancy, or autoinflammatory disorders. PAN has a broad spectrum of possible clinical manifestations the most common being constitutional symptoms, such as fever and myalgia. While cardiac involvement is well-described and is a common cause of mortality, it is exceedingly uncommon as the initial presentation. Below, we describe a case of a female in her 60s who presented with pericarditis as the first manifestation of PAN.

Annular vasculitic lesions

Vasculitic skin findings may present with annular morphologies. This group of conditions consists of capillaritis, such as pigmented purpuric dermatoses, and vasculitis, which is often classified by the affected vessel size. Annular vasculitic lesions may be the presenting sign of systemic disease, thus requiring thorough exploration to reach an accurate diagnosis and guide proper disease management. Herein we review the clinical presentation, histopathology, and treatments for cutaneous vasculitic disease that may present with annular lesions.

Reporting complete heart block in a patient with polyarteritis nodosa after COVID-19 vaccination

Complete heart block (CHB) is a serious health condition, and polyarteritis nodosa (PAN) is an important autoimmune disease. In the COVID-19 pandemy, several vaccines were developed for the COVID-19 disease that shown several side effects, and some of these complications are still unknown. This is the first report of CHB in a patient with history of PAN after COVID-19 vaccination. A 68-year-old man with a history of PAN referred to our hospital, complaining of presyncope episodes and dizziness after receiving a COVID-19 vaccine. Physical examination, laboratory tests, and transthoracic echocardiography were normal. In his electrocardiogram, a narrow QRS complex, AV dissociation, and junctional escape rhythm were seen. Coronary angiography showed a mild coronary artery disease. The patient, suffering from PAN for years, was hypothesized due to CHB a few days after COVID-19 vaccination. This case report suggests that COVID-19 vaccines may interrupt the conduction system of the heart and the fact that underlying PAN may predispose to CHB following COVID-19 vaccination. Further studies are needed to accurately assess a possible association between PAN, CHB, and COVID-19 vaccines.

Relationship Between Cerebrovascular Diseases and Vasculitis: A Cross-Sectional Nationwide Inpatient Study

Objectives

To evaluate the risk factors and hospitalization outcomes for cerebrovascular diseases (CVD) in patients with vasculitis.

Methods

We conducted a cross-sectional study using the Nationwide Inpatient Sample (NIS), 2019. We included 26,855 adults (aged 18 to 65 years, average age 48.57 ± 12.79 years) with a co-diagnosis of vasculitis, and the sample was divided by the primary diagnosis of CVD (N = 670, 2.5%). A demographic-adjusted logistic regression model was used to evaluate the odds ratio (OR) of association with CVD in patients with vasculitis by comparing it to the non-CVD cohort.

Results

The majority of the vasculitis patients with CVD were elders (51 to 65 years, 46%), females (62%), and whites (52%). There was a significant difference in the geographic distribution of CVD with vasculitis with the highest prevalence in the South Atlantic (23%) and Middle Atlantic (16%), and the lowest in the Mountain (4%) and New England (2%). Vasculitis patients with comorbid lymphoma (OR 2.46, P<0.001), peripheral vascular diseases (PVD (OR 1.54, P<0.001)), and complicated hypertension (OR 1.31, P<0.001) were associated with increasing the likelihood for CVD-related hospitalization. The mean length of stay was 13 days and the mean cost was $169,440 per CVD-related hospitalization in vasculitis patients. Cerebrovascular diseases in patients with vasculitis resulted in a major loss of body functioning (80%) leading to adverse disposition including transfer to a skilled nursing facility/intermediate care facility (22%) and requiring home health care (13%).

Conclusion

The prevalence of CVD-related hospitalization in vasculitis patients was 2.5% and females were observed to be at higher risk. Comorbid lymphoma, PVD, and hypertension further increase the risk for CVD with vasculitis. They have a higher loss of functioning that affects patient quality of life and require increased care after hospital discharge.

Polyarteritis nodosa: an evolving primary systemic vasculitis

Polyarteritis nodosa (PAN) is a primary form of vasculitis characterized by inflammation of primarily medium-sized arteries. Several key events have shaped the current spectrum of the disease including the separation of a subgroup with microscopic polyangiitis, the discovery of the association of hepatitis B, and the discovery of adenosine deaminase 2 deficiency (DADA2). With the discovery of secondary causes of PAN and changing nomenclature, the incidence of PAN has declined over time. Common manifestations include constitutional symptoms, skin involvement, peripheral neuropathy, gastrointestinal disease, and renal involvement. DADA2 is a genetic cause of medium vessel vasculitis that is important to distinguish from primary PAN as treatment with TNF inhibitors can prevent morbidity and mortality in those with a vasculitis phenotype. Treatment of systemic primary PAN involves the use of systemic immunosuppressive therapy largely guided by the severity of disease. With current treatment regimens, the prognosis has changed from a once uniformly fatal disease to a 5-year survival rate above 80%.

Remission of Angiographically Confirmed Minocycline-induced Renal Polyarteritis Nodosa: A Case Report and Literature Review

A 23-year-old man presented with severe hypertension. Based on his history of minocycline treatment for over three years and clinical symptoms, such as myalgias and renovascular hypertension with multiple intrarenal aneurysms, he was diagnosed with minocycline-induced renal polyarteritis nodosa (PAN). After minocycline treatment cessation and management of the hypertension, his blood pressure, renin-aldosterone levels, and urinary protein levels gradually improved. Seven and a half years later, repeated angiography found that the aneurysms had resolved. This is the first report in English describing a case of minocycline-induced renal PAN that was reversed functionally and morphologically without steroids or immunosuppressive drugs.

Therapeutic options for cutaneous polyarteritis nodosa: a systematic review

OBJECTIVE

Cutaneous polyarteritis nodosa (CPAN) is a necrotizing vasculitis of the middle-size vessels, confined to the skin. We conducted a systematic review in order to identify studies evaluating the different treatment modalities used in CPAN.

METHODS

This systematic review was conducted according to PRISMA guidelines, registered in PROSPERO: CRD42020222195. PubMed/Medline databases were searched from inception to December of 2020 using the terms: (Polyarteritis nodosa[Title/Abstract]) AND ((therapy[Title/Abstract]) OR (management[Title/Abstract]) OR (treatment[Title/Abstract]))' and 'Cutaneous arteritis [Title/Abstract]'. Articles evaluating pertaining to the management of CPAN in adults were eligible for inclusion.

RESULTS

A total of seven eligible case series with 325 unique patients were included. No study included a control population. In general, systemic corticosteroids were widely used as induction treatment. Immunosuppressive agents combined with corticosteroids were AZA, hydroxychloroquine, sulfasalazine, sulphapyridine, CYC, MTX, mycophenolate, tacrolimus, rituxima and thalidomide. Other agents utilized in the studies were dapsone, colchicine, non-steroid anti-inflammatory drugs, salicylates, warfarin and clopidogrel. In some studies, the presence of ulcerations was associated with an increased risk of relapse.

CONCLUSION

The evidence available regarding the management of patients with CPAN is limited at best. Further studies are needed in order to evaluate the effect of treatment on disease remission, relapses and mortality.

Clinical Characteristics and Outcomes of Mexican Patients With Polyarteritis Nodosa: A Single-Center Study Over 40 Years

METHODS

We conducted a medical records review study (1975-2018) that included patients with childhood- and adult-onset PAN. Demographics, organ involvement, phenotype, treatment, and outcomes were assessed and compared against previously published cohorts.

RESULTS

Thirty-one patients were included, 20 (64.5%) female, with a median age at diagnosis of 28 years (interquartile range [IQR], 16-42). Seven (23%) were classified as cutaneous; 23 (74%), systemic; and 1 (3%), progressive systemic phenotype. Eleven patients (35%) had childhood-onset PAN. Most common manifestations were musculoskeletal (71%), cutaneous (68%), constitutional (61%), peripheral neuropathy (39%), and gastrointestinal (29%). The median Birmingham Vasculitis Activity Score and Five-Factor Score at diagnosis were 9 (IQR, 4-13) and 1 (IQR, 0-1), respectively. Most patients were treated with glucocorticoids (94%). Twenty-four (80%) achieved complete and 6 (20%) partial remission at a median follow-up time of 30 months (8-192 months). The median Vasculitis Damage Index at last follow-up was 1 (IQR, 0-1). Nineteen (66%) experienced relapses. Patients with childhood-onset PAN more frequently had central nervous system and gastrointestinal involvement (36% vs 5%, p = 0.04 and 64% vs 10%, p = 0.003, respectively), microaneurysms (100% vs 38%, p = 0.02), and lower levels of C-reactive protein (0.3 vs 15.4 mg/dL, p = 0.03), compared with adult-onset PAN patients.

CONCLUSIONS

Our cohort of PAN patients showed predominantly a systemic phenotype. Outcomes were generally good, with most patients achieving complete remission. Childhood-onset differed from adult-onset PAN in terms of clinical and serological characteristics, whereas clinical manifestations and outcomes may be different than the ones reported in other cohorts.

Polyarteritis Nodosa: A Systematic Review of Test Accuracy and Benefits and Harms of Common Treatments

OBJECTIVE

The object of this study was to analyze the benefits and harms of different treatment options and to analyze test accuracy used in the evaluation of patients with primary systemic polyarteritis nodosa (PAN).

METHODS

A systematic search of published English-language literature was performed in Ovid Medline, PubMed, Embase, and the Cochrane Library from the inception of each database through August 2019. Articles were screened for suitability in addressing patient, intervention, comparison, and outcome questions, with studies presenting the highest level of evidence given preference.

RESULTS

Of 137 articles selected for data abstraction, we analyzed 21 observational studies and seven randomized controlled trials (RCTs). The results showed indirect evidence that a deep skin biopsy provides good diagnostic accuracy. A combined nerve and muscle biopsy should be obtained for patients with PAN with peripheral neuropathy. Cyclophosphamide with high-dose glucocorticoids (GCs) is effective as an induction treatment for newly diagnosed active and severe PAN. GC monotherapy is adequate in the majority of patients with nonsevere PAN, although it has a high relapse rate with GC taper. There was insufficient data in determining the optimal duration of non-GC and GC maintenance therapy. Tumor necrosis factor inhibitors are effective treatment for patients with deficiency of adenosine deaminase 2 (DADA2) with stroke and vasculitis manifestations.

CONCLUSION

This comprehensive systematic review synthesizes and evaluates the harms and benefits of different treatment options and the accuracy of commonly used tests for the diagnosis of systemic PAN. Data for diagnosis and management of PAN and DADA2 are mostly limited to observational studies. More high-quality RCTs are needed.

Infliximab for the treatment of refractory polyarteritis nodosa

Polyarteritis nodosa (PAN) is a necrotizing vasculitis predominantly affecting medium and small size arteries. Cyclophosphamide, a drug with narrow therapeutic range and poor safety profile, constitutes the treatment of choice for PAN vasculitis with major organ involvement. To describe our clinical experience in treating refractory PAN with infliximab (a TNF inhibitor), a drug with good tolerability and better safety profile than cyclophosphamide. Twenty-six PAN patients were admitted to our rheumatology unit between 2006 and 2017, of whom nine patients, with severe and refractory disease, were treated with infliximab after failure of standard treatment. We describe herein the patients' characteristics, clinical manifestations, severity and response to infliximab treatment and review the current literature. Complete remission was defined as the absence of features of active disease and withdrawal of prednisone therapy. Significant improvement was defined as clinical improvement and prednisone dose reduction of at least 50% or a 50% reduction in immune modulatory medications other than prednisone. After 4 months of treatment, 8/9 (89%) patients achieved significant improvement, with two of them achieving complete remission. We suggest that anti-TNF agents, and in particular infliximab, are relatively safe and efficacious treatment options in refractory PAN. A randomized controlled trial should be done in order to objectively evaluate infliximab in PAN.

Sudden Death Due to Coronary Arteritis

We report the case of a middle-aged man, without medical history, who suddenly died at his workplace. The autopsy highlighted a pathological heart macroscopically, with multiple small white areas on the left myocardium. Coronary dissection revealed a pseudotumoural fibromyxoid aspect within the anterior interventricular artery (AIVA) and the left main coronary trunk, including reduction in their diameter with tight stenosis. Microscopic examination of these arteries showed fibroinflammatory wall destruction. In the left myocardium, there were multiple focal ischemic areas at different stages of recovery. Our case is an illustration of primary ischemic heart disease due to coronary arteritis, with a pseudotumoural presentation, which was revealed by sudden death. We discuss the cause of death and the etiological diagnosis preceding coronary arteritis.

Vasculitis of the mesenteric circulation

Vasculitis of the mesenteric circulation is an uncommon but life-threatening manifestation of systemic vasculitis. Initial symptoms are frequently non-specific and therefore patients often present to primary care physicians and gastroenterologists with abdominal pain or gastrointestinal bleeding. Given the severity of the conditions associated with mesenteric vasculitis, it is imperative to appropriately diagnose and initiate treatment of suspected cases. This review will focus on diseases commonly associated with vasculitis of the mesenteric vessels. Imaging characteristics and clinical features assisting in diagnosis as well as initial approaches to treatment are emphasized.

Polyarteritis nodosa: A contemporary overview

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis predominantly targeting medium-sized arteries. PAN is a rare form of vasculitis, and the precise frequency of this disease is difficult to determine. The major environmental factor associated with PAN is HBV infection. The pathogenesis of "idiopathic PAN" remains enigmatic, although the clinical responses to immunosuppressive therapy support the concept that immunological mechanisms play an active pathogenic role. The spectrum of disease ranges from involving a single organ to polyvisceral failure. Any organ might be affected; however, for reasons that are not understood, PAN does not affect the lungs. In addition to the systemic idiopathic form, called "idiopathic generalized PAN," there are 2 clinical variants of this disease: "cutaneous PAN" and "hepatitis B virus (HBV)-associated PAN". Diagnosis requires the integration of clinical, angiographic, and biopsy findings. The overall prognosis of this disease has been improved in recent decades, primarily reflecting early diagnosis and more effective treatments. Idiopathic generalized PAN should be treated with a combination of glucocorticoids and cyclophosphamide. The treatment of HBV-associated PAN involves a different approach, centered on the use of an antiviral agent to control the infection. The therapy for cutaneous PAN requires a less aggressive approach based on the administration of non-steroidal anti-inflammatory drugs over short periods of time.

Isolated panniculitis with vasculitis of the male breast suspicious for malignancy on CT and ultrasound: a case report and literature review

Introduction

We report a case of a 54-year-old male patient with a hard, painful nodule within his right breast which was misdiagnosed preoperatively as breast cancer.

Case description

Preoperative work-up included physical examination, non-contrast chest computed tomography (CT), sonography, and sono-guided breast biopsy. Isolated breast panniculitis with vasculitis (BPWV), a rare disease, was diagnosed by histopathologic examination of tissue obtained from excisional biopsy.

Discussion and Evaluation

Subcutaneous panniculitis with or without vasculitis, a condition of nonsuppurative inflammatory process involving the subcutaneous fat layer of skin, is related to different causes. A palpable benign male breast lesion resembling a malignancy includes gynecomastia, panniculitis with or without vasculitis, fat necrosis, ruptured epidermal cyst, pseudoangiomatous stromal hyperplasia, subareolar abscess, intraductal papilloma, hematoma, and atypical fibroadenoma. To make an accurate preoperative diagnosis of a male breast mass, a physician has to carefully analyze various imaging findings. The cases of BPWV may present as an isolated breast lesion or as a component of a systemic disease. The diagnosis of the reported patient was compatible with an isolated BPWV because panniculitis and/or vasculitis were not present at other sites or organs at the time of diagnosis or during follow-up.

Conclusions

Excisional biopsy and clinical data can provide the correct diagnosis and determined the appropriate treatment strategy of a male BPWV.

Diagnosis and classification of polyarteritis nodosa

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

Primary systemic vasculitis with severe α1-antitrypsin deficiency revisited

OBJECTIVES

To study the clinical characteristics and epidemiology of the combination of primary systemic vasculitis (PSV) and severe alpha-1 antitrypsin (α1-AT) deficiency.

METHOD

Patients with PSV [granulomatosis with polyangiitis (GPA) (Wegener's), microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis (EGPA) (Churg-Strauss), and polyarteritis nodosa] were identified through diagnosis registries and serological databases. Clinical and laboratory data, including the presence of severe α1-AT deficiency, were collected from the time of diagnosis. During follow-up, data on relapses and permanent organ damage were collected. Using the county of Skåne as the denominator population, we estimated the annual incidence rate and point prevalence of PSV in people with severe α1-AT deficiency.

RESULTS

Five patients (three women, median age 49 years) with PSV diagnosed between 1996 and 2008 were found to have α1-AT deficiency, all of them carrying the protease inhibitor ZZ (PiZZ) phenotype. During follow-up (median time 166 months, range 53-208), four patients experienced a total of 13 relapses. The median Vasculitis Damage Index (VDI) score for all patients was 3 (range 1-4) at year 1, and 7 (range 3-9) at the last follow-up. The incidence rate of PSV among PiZZ carriers was estimated to be 397/million [95% confidence interval (CI) 8-787]. The point prevalence on 1 January 2013 was estimated to be 4689/million (95% CI 94-9285).

CONCLUSIONS

In this study both the incidence and prevalence of PSV were elevated nearly 10-fold for individuals with severe α1-AT deficiency compared with the general population. Combined with previous publications, this indicates a dose-response relationship for the genetic risk and suggests a causal relationship between the PiZ allele and vasculitis.

Diagnosis and treatment of cerebral vasculitis

Vasculitides are characterized by inflammation and necrosis of the blood vessel wall. Large vessels including the aorta are affected in giant-cell arteritis, medium-size arteries in classic polyarteritis nodosa. The small-vessel vasculitides are separated in those with antineutrophil cytoplasm antibodies (ANCA) and those without. The primary angiitis of the central nervous system (PACNS) is a rare disorder affecting both medium- and small-sized vessels. Major symptoms of cerebral vasculitis are stroke, headache and encephalopathy. Diagnosis is based on laboratory and imaging findings. When cerebral affection occurs in systemic vasculitis an acute inflammatory response with raised erythrocyte sedimentation rate and increased values of C-reactive protein is present. In many cerebral vasculitides including PACNS, CSF studies reveal inflammatory findings. Magnetic resonance imaging, including ADC maps, diffusion and gradient echo sequences, is the investigation of choice to detect and monitor cerebral involvement. Certain MRI techniques and 18-fluorodeoxyglucose positron emission tomography allow the visualization of vessel wall inflammation when the lumen is still unaffected on angiography. The treatment recommendations for cerebral angitis are derived from protocols for systemic vasculitides. In general, a combination of steroids and pulse cyclophosphamide (CYC) is recommended for induction treatment. An alternative option is the use of the anti- CD20 antibody rituximab. Methotrexate, azathioprine and mycophenolate mofetil are recommended as alternatives to CYC once remission is achieved.

Improvement in Relative Survival of Patients with Vasculitis: Study of 101 Cases Compared to the General Population

Immunosuppressive treatment has changed the prognosis of renal vasculitis over time, but improvement in prognosis is difficult to analyze in different historical periods, and can be better demonstrated by comparison with life expectancy of sex- and age-matched people. Long-term survival of 101 patients diagnosed with systemic vasculitis at our center from 1975 to 2002 was retrospectively evaluated in comparison with that of the Region's age- and sex-matched population. Patient and kidney survival significantly increased over time. Multivariate analyses showed that risks of patient and renal death decreased by 10% and 7%, respectively, at each year of follow-up, and increased by 6.3% and 5.2% for each year of age. Relative survival significantly improved over time, approaching that of the general population for cases diagnosed after 1993, mainly in women <60 years (from 0.671 at 5-years in the first period to 0.916 in the last period), while 5-year-relative-survival was still 0.530 and 0.682 in men and women > 60 years, respectively. Poisson-based multinomial analyses confirmed the significant risk of the first periods of diagnosis and of dialysis in worsening of the relative survival of patients compared to that of the general population. Life expectancy in patients with renal vasculitis has improved over time, paralleling a significant increase in steroid pulse/cyclophosphamide association therapy and an earlier diagnosis due to the introduction of the ANCA test. Relative survival has considerably improved, and now approaches that expected in the general population for women, but not for men.

Update on the use of biologics in primary systemic vasculitides

The introduction of biologic therapies, which selectively target components of the immune system, has revolutionized the treatment of rheumatoid arthritis. Anti-TNF-alpha therapy (infliximab, etanercept and adalimumab) and B-cell-depleting agents, such as rituximab, are the most widely used agents. Increased experience of the use of biologic drugs in other immune-mediated inflammatory diseases has led to the application of biologic therapies in the treatment of primary systemic vasculitis. Conversely, the success of biological agents has improved understanding of the immunopathogenesis of vascular inflammation. The need for biologic agents arises from the failure of the current standard of care to maintain remission while limiting drug toxicity. Evidence for the efficacy of biologic agents does not match that of conventional immunosuppressants yet, but it is building rapidly. This paper reviews the current evidence for the standard of care of patients with vasculitis and the role of biologic therapy in primary systemic vasculitis. In this review, we examine the rationale for using biologics based on the pathophysiology of primary systemic vasculitis. The risks and benefits of the use of biologics are discussed, together with future directions and predictions of these emerging therapies.

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 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.

Immunosuppressive treatment for non-systemic vasculitic neuropathy

BACKGROUND

Non-systemic vasculitic neuropathy is a rare disabling disease that usually has a subacute onset of progressive or relapsing-remitting sensory or sensorimotor deficits. Asymmetry, pain and weakness are key features. The diagnosis can only be made by exclusion of other causes, the absence of systemic vasculitis or other rheumatic diseases, and the demonstration of vasculitis in a nerve or a combined nerve and muscle biopsy. There is a need for efficacious therapy to prevent disease progression and to improve prognosis.

OBJECTIVES

To assess if immunosuppressive treatment in non-systemic vasculitic neuropathy reduces disability, and ameliorates neurological symptoms, and if such therapy can be given safely.

SEARCH STRATEGY

The Cochrane Neuromuscular Disease Group Trials Register (March 2006), The Cochrane Library (Issue 1, 2006), MEDLINE, EMBASE, LILACS, and ISI were searched from January 1980 until April 2006. In addition, the reference lists of relevant articles, reviews and textbooks were handsearched.

SELECTION CRITERIA

All randomised or quasi-randomised trials that examined the efficacy of immunosuppressive treatment for non-systemic vasculitic neuropathy at least one year after the onset of therapy were sought. Participants had to fulfill the following criteria: absence of systemic or neurological disease, exclusion of any recognised cause of the neuropathy by appropriate clinical or laboratory investigations, electrophysiological studies in agreement with axonal neuropathy, confirmation of vasculitis in a nerve or a combined nerve and muscle biopsy. The primary outcome measure was to be improvement in disability. Secondary outcome measures were to be change in the mean disability score, change in muscle strength measured with the Medical Research Council sum score, change in pain or other positive sensory symptoms, number of relapses, and adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed and extracted details of all potentially relevant trials. For included studies pooled relative risks and pooled weighted standardised mean differences were to be calculated to assess treatment efficacy.

MAIN RESULTS

Fifty-nine studies were identified and assessed for possible inclusion in the review, but all were excluded because of insufficient quality or lack of relevance.

AUTHORS' CONCLUSIONS

No adequate randomised or quasi-randomised controlled clinical trials have been performed on which to base treatment for non-systemic vasculitic neuropathy. Randomised trials of corticosteroids and other immunosuppressive agents are needed.

The challenge of managing patients with polyarteritis nodosa

PURPOSE OF REVIEW

In this short review we focus on the problems faced by clinicians caused by the changing definitions of polyarteritis nodosa.

RECENT FINDINGS

The term polyarteritis nodosa has been used for more than 100 years as a diagnostic term for patients with systemic vasculitis; however, specific vasculitides have been singled out like branches being chopped off a tree. Now, so little is left of the trunk of that tree that it is questionable to what extent we can trust older literature with respect to clinical features, natural history and response to treatment. Many authors of case reports, as well as authors of reviews and book chapters, claim they adhere to the Chapel Hill Consensus Conference definition of polyarteritis nodosa, yet still cite almost exclusively studies using older definitions without highlighting this dilemma. In the past year, two proposals affecting classification have been published: one stating that cutaneous polyarteritis nodosa and hepatitis-associated polyarteritis nodosa are diseases distinct from classical polyarteritis nodosa, and one providing an algorithm to separate microscopic polyangiitis from classical polyarteritis nodosa.

SUMMARY

There is hope that a wide acceptance of the new classification principles will lead to a more uniform way to diagnose classical polyarteritis nodosa, which will facilitate clinical studies and eventually improve management.