Giant cell arteritis is more prevalent in urban than in rural populations: results of an epidemiological study of primary systemic vasculitides in Germany

18-Fluorodeoxyglucose positron emission tomography/computed tomography for large vessel vasculitis in clinical practice

Diagnosis, prognostic assessment, and monitoring disease activity in patients with large vessel vasculitis (LVV) can be challenging. Early recognition of LVV and treatment adaptation is essential because vascular complications (aneurysm, dilatations, ischemic complications) or treatment related side effects can occur frequently in these patients. 18-fluorodeoxyglucose positron emission tomography/computed tomography (2-[18F]FDG-PET/CT) is increasingly used to diagnose, follow, and evaluate treatment response in LVV. In this review, we aimed to summarize the current evidence on the value of 2-[18F]FDG-PET/CT for diagnosis, follow, and treatment monitoring in LVV.

Environmental Triggers for Vasculitis

Systemic vasculitides are autoimmune diseases characterized by vascular inflammation. Most types of vasculitis are thought to result from antigen exposure in genetically susceptible individuals, suggesting a likely role for environmental triggers in these conditions. Seasonal and geographic variations in incidence provide insight into the potential role of environmental exposures in these diseases. Many data support infectious triggers in some vasculitides, whereas other studies have identified noninfectious triggers, such as airborne pollutants, silica, smoking, and heavy metals. We review the known and suspected environmental triggers in giant cell arteritis, Takayasu arteritis, polyarteritis nodosa, Kawasaki disease, and antineutrophil cytoplasmic antibody-associated vasculitis.

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.

Identification of differentially expressed genes and pathways in kidney of ANCA-associated vasculitis by integrated bioinformatics analysis

The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systematic of relatively rare autoimmune diseases with unknown cause. Kidney involvement is one of the most common clinical manifestations, and the degree of renal damage is closely associated with the development and prognosis of AAV. In this study, we utilized the Robust Rank Aggreg (RRA) method in R to integrate GSE104948, GSE104954, GSE108109, GSE108112, and GSE108113 profile datasets loaded from Gene Expression Omnibus (GEO) database and identified a set of differentially expressed genes (DEGs) in kidney between AAV patients and living donors. Then, the results of gene ontology (GO) functional annotation showed that immunity and metabolism involved process of AAV both in glomerulus and tubulointerstitial. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that following pathways, such as complement and coagulation cascades pathway; Staphylococcus aureus infection; disease-COVID-19; and systemic lupus erythematosus (SLE) pathway play a crucial role in AAV. Next, the results analyzed by protein–protein interaction (PPI) network and Cytoscape software exhibited the hub genes ALB, TYROBP, and CYBB existed in both glomerular and tubulointerstitial compartments datasets. Finally, KEGG analysis using genes of two most important modules also further validated complement and coagulation cascades pathway and S. aureus infection existed both in glomerulus and tubulointerstitial compartments datasets. In conclusion, this study identified key genes and pathways involved in kidney of AAV, which was benefit to further uncover the mechanisms underlying the development and progress of AAV, biomarkers, and potential therapeutic targets as well.

Prevalence of large vessel vasculitis in ANCA-associated vasculitis: a retrospective cohort study

ANCA-associated vasculitis (AAV) in general involves small blood vessels and includes granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA), and microscopic polyangiitis (MPA). Although reported in a few studies, the prevalence of large vessel vasculitis (LVV) in patients with AAV remains to be further explored. The goal of the present study was to assess the prevalence of LVV in a cohort of patients with AAV and to characterize this population. We conducted a ten-year retrospective study of a single-center cohort of AAV, including 101 patients with GPA (n = 58), EGPA (n = 28), MPA (n = 15), and compared the groups with or without associated LVV. LVV was diagnosed in five patients, two with aortitis and three with temporal arteritis, corresponding to a total prevalence of 5.0% [95% CI 1.6–11.2%]. This value was significantly higher than the estimated prevalence of LVV in the normal Swiss population (OR 234.9 95% CI 91.18–605.2, p < 0.001). All five patients had GPA, whereas no cases with EGPA or MPA were identified. Anti-PR3 antibodies were detected in four out of five patients, anti-MPO in one patient. Since LVV can occur in a significant proportion of patients with GPA, evaluation for LVV may be considered systematically in the diagnostic workup of AAV.

ANCA-associated renal vasculitis is associated with rurality but not seasonality or deprivation in a complete national cohort study

Background

Small studies suggest an association between ANCA-associated vasculitis (AAV) incidence and rurality, seasonality and socioeconomic deprivation. We examined the incidence of kidney biopsy-proven AAV and its relationship with these factors in the adult Scottish population.

Methods

Using the Scottish Renal Biopsy Registry, all adult native kidney biopsies performed between 2014 and 2018 with a diagnosis of granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) were identified. The Scottish Government Urban Rural Classification was used for rurality analysis. Seasons were defined as autumn (September–November), winter (December–February), spring (March–May) and summer (June–August). Patients were separated into quintiles of socioeconomic deprivation using the validated Scottish Index of Multiple Deprivation and incidence standardised to age. Estimated glomerular filtration rate and urine protein:creatinine ratio at time of biopsy were used to assess disease severity.

Results

339 cases of renal AAV were identified, of which 62% had MPA and 38% had GPA diagnosis. AAV incidence was 15.1 per million population per year (pmp/year). Mean age was 66 years and 54% were female. Incidence of GPA (but not MPA) was positively associated with rurality (5.2, 8.4 and 9.1 pmp/year in ‘urban’, ‘accessible remote’ and ‘rural remote’ areas, respectively; p=0.04). The age-standardised incidence ratio was similar across all quintiles of deprivation (p=ns).

Conclusions

Seasonality and disease severity did not vary across AAV study groups. In this complete national cohort study, we observed a positive association between kidney biopsy-proven GPA and rurality.

An update on the epidemiology of ANCA-associated vasculitis

ANCA-associated vasculitis (AAV) includes granulomatosis with polyangiitis, microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis. Epidemiological studies in AAV are important in understanding possible aetiologic mechanisms and facilitating healthcare planning. However, epidemiological studies present a number of challenges including clear definition of cases differentiated from other clinical disorders, and identification of cases due to the rarity of AAV. The aim of this review is to summarize different aspects on the epidemiology of ANCA-associated vasculitis from different geographical areas throughout the world. During the past three decades, development of classification criteria worldwide, including the ACR classification of 1990, the Chapel Hill consensus definitions updated in 2012 and the EMA algorithm has facilitated epidemiology studies in AAV. The available epidemiological studies reported in AAV suggest that incidence and prevalence may have increased over the past 30 years. Possible explanations for this increase may be a genuine increase in incidence, the evolution of classification criteria and the definition, and availability and wider use of ANCA serology to aid diagnosis, and greater physician awareness through education. The age-specific incidence for the whole group of AAV showed a clear increase with age. However, there has been a clear shift in the peak age at onset towards a higher age during the last 20-30 years. In addition, variation in incidence of AAV between men and women has been clearly evident in a number of epidemiological studies.

Vasculitis

Vasculitis, characterized by inflammation and necrosis, manifests a wide spectrum of presentation by involving a vasculature of various sizes and locations. A definitive diagnosis of vasculitis invariably requires histologic confirmation since there are no diagnostic clinical, imaging, or laboratory findings. The most widely adopted vasculitis classification is the Chapel Hill Consensus Conference (CHCC) nomenclature of systemic vasculitis which integrated clinical symptoms, histopathologic features, and laboratory findings. This classification accounts for the size of the involved vessels. This chapter outlines the clinical and histologic features of the small-vessel vasculitis including the immune complex vasculitis and antineutrophil cytoplasmic antibody-associated vasculitis; medium-vessel vasculitis such as polyarteritis nodosa and Kawasaki disease; large-vessel vasculitis, namely, giant cell arteritis and Takayasu arteritis; variable-vessel vasculitis such as Behcet disease and Cogan syndrome; and vasculitis associated with systemic diseases including rheumatoid arthritis, lupus vasculitis, and sarcoid vasculitis. Vasculitis can also be secondary to drugs, infection, underlying systemic disease, or trauma. Therefore, a diagnosis of vasculitis cannot be based on histologic ground alone. Clinical pathologic correlation is necessary.

[Update: polyarteritis nodosa]

Polyarteritis nodosa (PAN) is a necrotizing arteritis of medium-sized vessels, which is often fatal if untreated. It frequently affects the skin (nodules and ulcers), the peripheral nervous system (mononeuritis multiplex) and the visceral vessels (stenoses and microaneurysms). The complex diagnostic work-up requires discriminating PAN from infectious, malignant, drug-induced and other inflammatory conditions. It can be subclassified into further variants (idiopathic, associated with hepatitis B, associated with hereditary inflammatory diseases or isolated cutaneous disease). While idiopathic and hereditary inflammatory variants require immunosuppressive treatment, the hepatitis B-associated variant is treated with virustatic agents and plasmapheresis. The isolated cutaneous variant has a good prognosis and rarely requires highly potent immunosuppressives.

Epidemiology and clinical features of childhood-onset anti-neutrophil cytoplasmic antibody-associated vasculitis: a clinicopathological analysis

BACKGROUND

This study was performed to determine the clinical features and outcomes of childhood-onset anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), particularly microscopic polyangiitis (MPA).

METHODS

A retrospective Japanese multicenter study was performed in patients diagnosed with AAV before 16 years of age.

RESULTS

Of 49 patients with AAV, 36 were female. The diagnoses were as follows: MPA (n = 38, 78%), granulomatosis with polyangiitis (GPA; n = 9, 18%), eosinophilic granulomatosis with polyangiitis (EGPA; n = 1, 2%), and other (n = 1, 2%). The median age at onset was 10.7 years, and median time to diagnosis was 2.0 months. Twenty-seven (55%) patients were identified through a school urinary screening program. Initial symptoms included fever and fatigue (45%), and renal (71%), pulmonary (29%), ocular (20%), and mucocutaneous involvement (22%). Although 27 (55%) patients achieved remission and none had died at the last follow-up, at least one recurrence occurred in 13 (48%) patients after a median of 48 months and was more common in patients with GPA (P < 0.01). After a median follow-up of 43 months, seven (14%) patients (all with MPA) progressed to end-stage renal disease (ESRD).

CONCLUSIONS

Childhood-onset AAV has an estimated prevalence of 3.41-4.28 per million children and is characterized by female predominance and high frequency of detection in school urinary screening programs. More than 10% of patients with childhood-onset AAV still progress to ESRD without achieving remission. Histological chronicity is a factor associated with ESRD.

Temporal and Cartographic Analyses of the Distribution within Spain of Mortality Due to Granulomatosis with Polyangiitis (1984⁻2016)

The aim is to conduct a descriptive, population-based study in order to assess temporal and spatial changes in mortality due to granulomatosis with polyangiitis (GPA) in Spain from 1984 to 2016. Mortality data were obtained from the Spanish Annual Death Registry. Deaths in which GPA was the underlying cause were selected using the 446.4 and M31.3 codes from the International Classification of Diseases, 9th and 10th revision. Annual average age at death and age-adjusted mortality rates were calculated. Geographic analysis was performed at municipality and district level. Variations in mortality according to the type of municipality (urban, agro-urban or rural), district and geographic location (degrees of latitude) were assessed using standardized mortality ratios (SMRs) and smoothed-SMRs. Over the whole period, 620 deaths due to GPA were identified. Age at death increased at an average annual rate of 0.78% over the period 1987–2016 (p < 0.05). Age-adjusted mortality rates increased by an annual average of 20.58% from 1984 to 1992, after which they fell by 1.91% a year (p < 0.05). The agro-urban category had the highest percentage (4.57%) of municipalities with a significantly higher GPA mortality rate than expected. Geographic analysis revealed four districts with a higher risk of death due to GPA, two in the North of Spain and two in the South. This population-based study revealed an increase in the age at death attributed to GPA. Age-adjusted mortality rates went up sharply until 1992, after which they started to decline until the end of the study period. Geographic differences in mortality risk were identified but further studies will be necessary to ascertain the reasons for the distribution of GPA disease.

Incidence of giant cell arteritis in Western Norway 1972-2012: a retrospective cohort study

Background

Giant cell arteritis (GCA) is the most common systemic vasculitis in persons older than 50 years. The highest incidence rates of the disease have been reported in Scandinavian countries. Our objective was to determine the epidemiology of GCA in an expected high-incidence region during a 41-year period.

Methods

This is a hospital-based, retrospective, cohort study. Patients diagnosed with GCA in Bergen health area during 1972–2012 were identified through computerized hospital records (n = 1341). Clinical information was extracted from patients’ medical journals, which were reviewed by a standardized method. We excluded patients if data were unavailable (n = 253), if the reviewing rheumatologist found GCA to be an implausible diagnosis (n = 207) or if the American College of Rheumatology (ACR) 1990 classification criteria for GCA were not fulfilled (n = 89). Descriptive methods were used to characterize the sample. Incidence was analyzed by graphical methods and Poisson regression.

Results

A total of 792 patients were included. The average annual cumulative incidence of GCA was 16.7 (95% CI 15.5-18.0) per 100,000 of the population ≥ 50 years old. The corresponding incidence for biopsy-verified GCA was 11.2 (95% CI 10.2–12.3). The annual cumulative incidence increased with time in the period 1972–1992 (relative risk (RR) 1.1, p < 0.001) but not in 1993–2012 (RR 1.0, p = 0.543). The incidence was higher in women compared to men (average annual incidence 37.7 (95% CI 35.8–39.6) vs. 14.3 (95% CI 13.2–15.5), p < 0.001) with women having a twofold to threefold higher incidence rate throughout the study period. Average annual incidence increased with age until the 7th decade of life in both sexes throughout the study period (2.8 (95% CI 2.3–3.3) for age <60, 15.5 (95% CI 14.4–16.8) for age 60–69, 34.5 (95% CI 32.8–36.4) for age 70–79 and 26.8 (95% CI 25.3-28.4) for age ≥80 years, p < 0.001 for all age adjustments).

Conclusions

Our study confirms an incidence of GCA comparable to previous reports on Scandinavian populations. Our results show increasing incidence from 1972 through 1992, after which the incidence has levelled out.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1479-6) contains supplementary material, which is available to authorized users.

Geo-epidemiology of temporal artery biopsy-positive giant cell arteritis in Australia and New Zealand: is there a seasonal influence?

Objective

Previous studies, although inconclusive, have suggested possible associations of environmental risk factors with the development of giant cell arteritis (GCA). We aim to investigate seasonal influence on the incidence of GCA across Australia and New Zealand.

Methods

In establishing an international study to investigate the molecular aetiology of GCA, archived temporal artery biopsy (TAB) specimens primarily from Australia and New Zealand were obtained. Demographic details including age, sex and date of TAB were collected from collaborating pathology departments. The season in which GCA was diagnosed was determined and compared with previous reports investigating the association between environmental risk factors and GCA.

Results

Our study comprises data from 2224 TAB-positive patients with GCA; 2099 of which were from patients in Australia and New Zealand. The mean age at time of diagnosis was 76.4 years of age. The female-to-male ratio was 2.2:1. We noted equal distribution of the incidence rate across all four seasons (530-580 cases diagnosed every quarter). Statistical analysis of seasonal variation by Poisson regression and cosinor methods showed no incidence preponderance across seasons. Our results do not support a seasonal component contributing to the onset of disease. Our literature search identifies no consistent environmental risk factor in association with GCA.

Conclusion

This is the largest GCA data set reported outside of Europe. Our results demonstrate equal distribution of the incidence rate across all four seasons. In contrast to some earlier reports, we did not identify evidence of a seasonal component contributing to the onset of disease.

[Kawasaki disease is more prevalent in rural areas of Catalonia (Spain)]

INTRODUCTION

Kawasaki disease (KD) is an acute self-limited systemic vasculitis relatively common in childhood. The etiology of KD is still unknown, although clinical, laboratory and epidemiological features suggest an infectious origin or trigger. Differences on incidence between countries have been related to specific genetic factors, ethnicity, country of birth and some other sociocultural and environmental factors. We present a population-based study on incidence of KD in Catalonia (Spain), focusing on differences between patients in rural and non-rural areas of the region.

METHODS

Observational population-based study including all Pediatric Units in Catalan hospitals, between 2004 and 2014. A 12-month (March 2013-March 2014) prospective collection of new cases of KD was carried out to determine the incidence of KD. The rest of the data was retrieved retrospectively.

RESULTS

Data from 399 patients over the 10-year study period was analyzed. Among the total KD patients, 353 (88.5%) lived in non-rural areas and 46 (11.5%) in rural areas. It was found that there is a significant difference (P<.001) between the percentage of rural population observed in patients with KD (11.5%), and the expected 5% of the Catalan population.

CONCLUSION

This is the first population-based study showing significant differences on KD incidence rates between rural and non-rural areas.

Classification, epidemiology and clinical subgrouping of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis

It is now 25 years since the first European studies on vasculitis--the anti-neutrophil cytoplasmic antibody (ANCA) standardization project. Over that period of time, there have been major developments in the classification of the vasculitides, which has permitted the conduct of high-quality epidemiology studies. Studying the epidemiology of rare diseases such as the ANCA-associated vasculitides (AAV) poses considerable challenges to epidemiologists. The first is the need for a clear definition of a case with good differentiation from similar disorders. The second is case capture. The vasculitides are rare, and therefore, a large population is required to determine the incidence and prevalence, and this poses questions of feasibility. A large population increases the risk of incomplete case detection but permits a reasonable number of cases to be collected in a practicable time frame, whereas a smaller population requires a much longer time frame to collect the necessary cases, which may also not be feasible. Statistical methods of capture-recapture analysis enable estimates to be made of the number of missing cases. The third is case ascertainment. The AAV are virtually always managed in secondary care, and therefore, hospital-based case ascertainment may be appropriate. Fourthly, the rarity of the conditions makes prospective case-control studies investigating risk factors difficult to conduct because the population size required to achieve statistical confidence is in excess of that which is readily available. Thus, much of the data on risk factors are derived from retrospective studies with inherent potential bias.

[Giant cell arteritis: etiological knowledge and diagnostic challenge for pathologists]

Giant cell arteritis is a potentially systemic disease of medium-sized and large caliber arteries, showing a preferential manifestation in the extracranial branches of the carotid artery. The diagnosis is oriented to clinical and histomorphological criteria which will be critically reviewed. Particular emphasis is placed on the differentiation from normal aging processes and from healing stages under steroid therapy. In addition, the advances in our understanding of the disease pathomechanism during the last 10 years will be briefly presented as the basis for the hitherto empiric steroid treatment.

Wegener's granulomatosis presenting as meningitis

BACKGROUND

Wegener's granulomatosis is a rare but well recognised autoimmune necrotising vasculitis. Presentation of disease in the head and neck is common and mostly consists of nasal crusting, blockage and bloody discharge. Neurological presentation is very uncommon.

METHODS

We report a patient who presented to the medical emergency services with signs and symptoms of meningitis, but who was eventually diagnosed with Wegener's granulomatosis. A literature search on this topic was carried out using Medline and Embase (1996 to 2011), searching for 'Wegener's granulomatosis' and 'meningitis'.

RESULTS

After thorough neurological and medical investigation, a combination of brain computed tomography, lumbar puncture, nasal biopsy and laboratory results refuted the diagnosis of meningitis and confirmed the diagnosis of Wegener's granulomatosis.

CONCLUSION

To the best of our knowledge, this is the first English-language case report of a patient with Wegener's granulomatosis presenting with symptoms of meningitis unconfirmed on computed tomography and lumbar puncture.

Nasal surgery in patients with systemic disorders

Multisystemic disorders represent a heterogenous group of diseases which can primarily manifest at the nose and paranasal sinuses as limited disease or secondarily as part of systemic involvement. Rhinologists therefore play an important role in the diagnostic but also therapeutic process. Although therapy of multisystemic disorders is primary systemic, additional rhinosurgery may become necessary. The spectrum of procedures consists of sinus surgery, surgery of the orbit and lacrimal duct, septorhinoplasty and closure of nasal septal perforation. Since the prevalence of most systemic diseases is very rare, recommendations are based on the analysis of single case reports and case series with a limited number of patients only. Although data is still limited, experiences published so far have shown that autologous cartilage or bone grafts can be used in nasal reconstruction of deformities caused by tuberculosis, leprosy, Wegener’s granulomatosis, sarcoidosis and relapsing polychondritis. Experiences gained from these diseases support the concept that well-established techniques of septorhinoplasty can be used in systemic diseases as well. However, a state of remission is an essential condition before considering any rhinosurgery in these patients. Even under these circumstances revision surgery has to be expected more frequently compared to the typical collective of patients undergoing septorhinoplasty. In addition, experiences gained from saddle nose reconstruction may in part be of value for the treatment of nasal septal perforations since implantation of cartilage grafts often represents an essential step in multilayer techniques of closure of nasal septal perforations. Aside from the treatment of orbital complications sinus surgery has been proven beneficial in reducing nasal symptoms and increasing quality of life in patients refractory to systemic treatment.

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.

Pathogenesis of giant cell arteritis: More than just an inflammatory condition?

Giant cell arteritis (GCA) is characterized by intimal hyperplasia and luminal obstruction leading to ischemic manifestations involving extra-cranial branches of carotid arteries and aorta. Histopathological lesions involve all layers of the arterial wall and are associated with multinucleated giant cells, fragmented internal elastic lamina and polymorphic cellular infiltrates, including T lymphocytes and macrophages. The pathophysiology of GCA is still poorly understood. After dendritic cell activation, CD4(+) T lymphocytes, T helper 1 (Th1) cells, produce interferon gamma and modulate macrophage activation and functions, and Th17 cells produce interleukin 17 (IL-17), which can induce cytokine production by macrophages and fibroblasts. Macrophages in the adventitia produce pro-inflammatory cytokines such as IL-1, IL-6 and tumor necrosis factor alpha. These cytokines promote arterial wall and systemic inflammation. Questions remain regarding the nature of the antigen(s) triggering dendritic cell activation and the mechanisms underlying vascular remodeling. Here we review recent advances in the pathogenesis of GCA, with emphasis on the interactions between cells of the immune system and components of the vessel wall, including vascular smooth muscle cells and endothelial cells, leading to vascular remodeling. Finally, we propose new areas of investigation that could help understand the triggering factors and key pathogenic events in GCA.

Chemosensory function in Wegener's granulomatosis: a preliminary report

Despite the fact that Wegener's granulomatosis affects the nasal and paranasal cavities and the cranial nerves regularly, chemosensory impairments have not been reported. The objective of this study is to test the three chemosensory systems, olfaction, taste, and intranasal trigeminal function in Wegener disease patients. We tested olfactory, gustatory, and intranasal trigeminal function in nine patients (5 women, 4 men, mean age 57 years) with confirmed Wegener's granulomatosis. Olfaction was tested with the Sniffin'Sticks, gustatory function with the "Taste strips" and intranasal trigeminal function with a lateralization task. One patient had anosmia (11%), four patients had hyposmia (44%) and four patients were normosmic (45%). Gustatory testing function showed pathological taste strip results in five patients (55%) and normal results in three patients (33%). One patient did not undergo taste testing. Intranasal trigeminal function was lowered in five patients (56%) and normal in four patients (44%). Neither previous nasal surgery status nor endoscopic status was associated to a higher frequency in pathological scores for any of the three chemical senses. In conclusion, these preliminary results suggest a consistent affection in chemosensory functions in Wegener's granulomatosis patients.

Bilateral renal hemorrhage due to polyarteritis nodosa wrongly attributed to blunt trauma

BACKGROUND

A 36-year-old, previously healthy man presented to an accident and emergency department with right-sided abdominal pain 7 days after he sustained a trauma to his right flank. He was using no medication other than over-the-counter analgesics since his injury.

INVESTIGATIONS

Complete blood count, serum creatinine measurement, liver function tests, hepatitis B and C screening, abdominal CT, renal angiography, surgical exploration and histology of kidney samples.

DIAGNOSIS

Polyarteritis nodosa with Page kidney causing bilateral perirenal hematoma, severe hypertension and renal failure.

MANAGEMENT

The patient was severely anemic, and his bleeding was investigated. A 15 x 13 x 12 cm retroperitoneal hematoma was found in the region of the right kidney and the patient underwent unilateral right nephrectomy. 3 weeks after discharge the patient was readmitted with a left-sided perirenal hematoma. Steel-coil embolization of the kidney stopped the bleeding but the patient developed hypertension and renal failure, and antihypertensive agents and dialysis were started. Microaneurysms and vessel-wall necrosis were discovered on re-examination of the angiogram and histology, respectively, so immunosuppressive therapy was started, comprising intravenous methylprednisolone daily for 3 days and oral prednisolone and intravenous cyclophosphamide for 4 weeks. Page kidney, resulting from the bleeding into the solitary kidney, caused stretching of the renal artery and deterioration of renal function, which required hemodialysis treatment.

[Clinical and serological findings of giant-cell arteritis]

Giant cell arteritis (GCA) frequently appears as cranial arteritis (eg. temporal arteritis) with headache, pain on chewing and visual disturbances. In addition, extracranial manifestations are often observed leading to aneurysmatic dilatations and dissections of the aorta as well as stenoses of large thoracic, abdominal or limb arteries. The vascular signs are accompanied by general disease symptoms, e.g. malaise, elevated temperatures, weight loss and depression. Polymyalgia rheumatica (PMR) is the most frequent rheumatic manifestation of GCA but also occurs independently from GCA. The structural correlate for the PMR symptoms is first and foremost extra-articular inflammation (tenosynovitis, bursitis) of large joints and the vertebral column (interspinal bursitis). In addition, vasculitis of large arteries in PMR must be considered particularly in the presence of high inflammatory activity. While specific laboratory markers for GCA and PMR are lacking elevated values for the erythrocyte sedimentation rate and C-reactive protein are present in almost all patients at disease onset. Besides the clinical evaluation, the serological acute phase reaction represents the main parameter for the course during therapy of this relatively frequent disease in elderly people.

Incidence and survival rates in Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome and polyarteritis nodosa

OBJECTIVE

To estimate the incidence of and survival rates for WG, microscopic polyangiitis (MPA), Churg-Strauss syndrome (CSS) and PAN within a defined population in southern Sweden.

METHODS

Cases were retrieved using hospital records and a serology database. All new cases of WG, MPA, CSS and PAN between 1997 and 2006 were included, provided they met pre-defined criteria, and were followed until 30 June 2008. The study area comprised two health care districts with a total population of 641 000. The standardized mortality ratio (SMR) was estimated using Swedish population data as a reference.

RESULTS

A total of 140 (WG, 63; MPA 65; CSS 6; and PAN 6) cases (52% women) with a median age of 67.6 (range 20-96) years fulfilled the inclusion criteria. The annual incidence per million of the population (95% CI) was estimated to be 9.8 (7.4-12.2) for WG, 10.1 (7.7-12.6) for MPA and 0.9 (0-1.7) for both CSS and PAN. The highest incidence was found in patients aged >or=75 years (79.1/million). The 1- and 5-year survival rates were 87.8 and 71.6% for all patients, but lower for MPA (80 and 55%) compared with WG (95 and 83%; P = 0.001), although the difference was not significant in the multivariate analysis. The SMR was 2.77 (95% CI 2.02, 3.71) for all patients.

CONCLUSIONS

The incidence of WG and MPA was equal in our district, but there was a difference in survival rates related to age and renal function. A progressive increase in age-specific incidence rates was observed.

Churg-strauss syndrome in patients treated with omalizumab

BACKGROUND

Churg-Strauss syndrome (CSS) is a rare systemic vasculitis associated with asthma, eosinophilia, sinusitis, and pulmonary infiltrates. CSS has been reported in association with asthma therapies.

MATERIALS AND METHODS

The objective is to describe the characteristics of CSS in patients treated with the anti-IgE antibody omalizumab (Xolair; Genentech Inc; South San Francisco, CA). A retrospective review of available data to identify cases of CSS was performed using the Novartis Argus global drug safety database for omalizumab in asthma patients.

RESULTS

We identified 34 potential cases of CSS. Of these, 13 cases fulfilled at least four of the six criteria identified in the American College of Rheumatology classification criteria. Eight of the patients in these 13 definite or probable cases (62%) had CSS symptoms prior to receiving omalizumab or described symptom onset just after corticosteroid weaning. Six of the 13 patients (46%) were confirmed as having been treated with corticosteroids for what was perceived to be severe asthma; when corticosteroids were tapered in conjunction with omalizumab treatment, CSS symptoms appeared just after the tapering. There were 4 other cases of possible CSS, and the remaining 17 patients were judged to not have CSS.

CONCLUSIONS

CSS may develop in patients receiving asthma medications who have an underlying eosinophilic disorder that is unmasked by the withdrawal of therapy with corticosteroids, or in patients who delay therapy in favor of other medications. Omalizumab treatment may unmask CSS due to the weaning of corticosteroids in some asthma patients or may delay corticosteroid treatment allowing for CSS to manifest.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00252135.

The geo-epidemiology of temporal (giant cell) arteritis

Giant cell arteritis (GCA) is the most common vasculopathy in patients over the age of 50. The majority of data on the geo-epidemiology of GCA is derived from Scandinavia, although there is very good documentation and epidemiological descriptions from studies throughout Europe and North America. There remains, however, a paucity of data on the incidence and prevalence of GCA in North American minority populations, as well as from Africa or Asia. The data that does exist suggests that the incidence of GCA is lower in Hispanic, Asian, and African American populations. It is interesting to note that as the population throughout the world continues to age, we anticipate an increased prevalence of disease based upon increases in annual incidence and improved survival. Considerable research is still needed to identify genetic, environmental, and gender-specific factors that influence not only the etiology, but also the natural history of disease.

Wegener's granulomatosis in New Zealand: evidence for a latitude-dependent incidence gradient

BACKGROUND

The aim of the study was to determine whether there was evidence for a geographic gradient in the incidence of Wegener's granulomatosis (WG) and WG-like disease in New Zealand (NZ).

METHODS

The National Minimum Dataset of the Ministry of Health, NZ was searched for individual patient discharges coded by the International Classification of Diseases 10th Revision, Australian Modification as either M301 (polyarteritis with lung involvement, including Churg Strauss and allergic granulomatous angiitis) or M313 (WG, necrotizing respiratory granulomatosis) for the period 1 January 1999 to 31 December 2003. Data were standardized using the 2001 NZ census.

RESULTS

One hundred and ninety-five patients (95 men) were given a first-time discharge code of either M301 (40 patients) or M313 (155 patients). No gender bias was seen. The rate among Europeans was twice that of NZ Maoris or Asians. The rate of disease peaked in the age band 70-79 years and during winter months. A significant positive north-south geographic gradient was present for M313. No difference in the rate of readmission or time to relapse between geographic regions was found for M313.

CONCLUSION

A north-south gradient in the rate of patient discharges given a diagnostic code of M313 (WG, necrotizing respiratory granulomatosis) was present in NZ. This finding supports the hypothesis that there is a latitude-dependent risk factor(s) for WG possibly common to both global hemispheres.

[Giant cell arteritis (temporal arteritis). Pathophysiology, immunology]

The diagnosis of giant cell arteritis is established by temporal artery biopsy. The findings are those of a panarteritis with mononuclear infiltrates penetrating all layers of the arterial wall. Typically, activated T cells and macrophages are arranged in granulomas. Multinucleated giant cells, when present, are usually close to the fragmented internal elastic lamina. Often, the intimal layer is hyperplastic, leading to concentric occlusion of the lumen. The CD4(+) T cells are the main players in the disease process. T-cell activation in the arterial wall requires the presence of specialized antigen-presenting cells, the dendritic cells. The activation of monocytes and macrophages is responsible for the systemic inflammatory syndrome in giant cell arteritis and polymyalgia rheumatica. The blood vessel wall determines the site specificity of giant cell arteritis and provides the ground for the cell to cell interaction.

Epidemiology of systemic vasculitis

The systemic vasculitides are heterogeneous conditions of unknown etiology characterized by inflammation and necrosis of different sized blood vessels. Wegener's Granulomatosis, microscopic polyangiitis, and Churg Strauss syndrome are associated with anti-neutrophil cytoplasmic antibodies and affect small and medium blood vessels. They are very rare in childhood and peak in the 65 to 70 year old age group. Wegener's Granulomatosis appears to be more common in the North of Europe compared with the South. All are more common in whites compared with other populations. Genetic and environmental factors, including infection, drugs, and silica, are important in etiology. Giant cell arteritis is predominantly a disease of whites over the age of 50. It appears more common in individuals with Nordic descent. Incidence may be increasing over time and cyclical variation in disease may reflect an infectious etiology. Takayasu arteritis is a disease of the aorta and its branches, however pulmonary and cardiac arteries may be involved. Patients are usually under 40-years of age at presentation and there are no apparent differences in incidence or clinical characteristics/aortic involvement across the globe. Kawasaki disease (KD) and Henoch-Schonlein purpura are diseases of children and rarely affect adults. Both have been reported to be more common in Asians than whites. The incidence of KD is higher in Japan and China compared with other regions. No definite trigger factors have been found, but KD has been linked to infection, house dust mite and chemicals, and Henoch-Schonlein purpura to a pesticide and drugs.

Frühdiagnose von Vaskulitiden

The often unspecific symptoms like myalgias, fever and weight loss at the onset of vasculitides are a frequent cause for a delay in diagnosis. Organ-specific symptoms like hemoptysis, dyspnoea, epistaxis, edema and organ infarcts a present when organ dysfunction occurs as a result of vasculitis. Targeted serologic testing including antineutrophil cytoplasm antibodies (ANCA) and cryoglobulins allows early diagnosis of certain vasculitides. Modern imaging techniques like magnetic resonance imaging, computed tomography, positron-emission tomography and ultrasound are cornerstones for an early diagnosis as they allow the detection of subclinical disease and are helpful in the identification of a site for biopsy. Bioptic proof of vasculitis is still the gold standard for diagnosis. Functionally relevant damage caused by systemic inflammatory disorders can by reduced or sometimes avoided by early initiation of treatment. This requires a correct diagnosis is made as early as possible.

Difficult to diagnose manifestations of vasculitis: Does an interdisciplinary approach help?

In the early stages of disease, primary systemic vasculitides often present with non-specific symptoms that make early diagnosis a challenge. The variety of clinical manifestations found in systemic vasculitis is huge, and some manifestations are frequently not clinically overt at first presentation. A logical implication of the often non-specific and sometimes subclinical presentation of vasculitis is that a systematic diagnostic work-up is necessary. This requires a multidisciplinary approach involving the expert opinion of specialists from many disciplines, such as neurology, radiology, respiratory medicine, pathology and microbiology. There are no generally accepted diagnostic criteria for primary systemic vasculitides, and the application of classification criteria as diagnostic criteria is not feasible and may even be misleading. The demonstration of vasculitis on biopsy is still the gold standard for the diagnosis of vasculitis. In cases where biopsies cannot be obtained, surrogate parameters of vasculitis (e.g. glomerular hematuria or mononeuritis multiplex), along with serology and imaging, can support a clinical diagnosis of vasculitis. This review discusses the approach to the diagnosis of central nervous system and pulmonary manifestations of primary systemic vasculitis. These two examples of difficult to diagnose manifestations of vasculitis illustrate the necessity of an interdisciplinary approach to the diagnostic work-up.