Classification of vasculitis.

Usually classifications of vasculitic syndromes are based on clinical and histopathologic findings because pathogenetic mechanisms are poorly understood. A subcommittee of the Diagnostic and Therapeutic Criteria Committee of the American College of Rheumatology recently developed classification criteria for seven major vasculitic disorders through the analysis of prospectively collected patient data from 48 centers. Using two classification methods, the subcommittee derived criteria for polyareritis nodosa, Churg-Strauss syndrome, Wegner's granulomatosis, hypersensitivity vasculitis, Henoch-Sch?nlein purpura, giant cell (temporal) arteritis, and Takayasu's arteritis. Although such criteria may identify typical patients with a distinct form of vasculitis, they are not intended to establish a diagnosis in an individual patient; rather, they should aid comparability of different patient groups in various research endeavors.     

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.     

Temporal arteritis associated with systemic necrotizing vasculitis

OBJECTIVE: To evaluate the clinical and laboratory characteristics of patients with systemic vasculitis associated with temporal artery involvement. METHODS: From a cohort of 120 patients fulfilling American College of Rheumatology criteria for temporal arteritis, we retrospectively identified 7 patients with systemic necrotizing vasculitis associated with histological temporal arteritis. RESULTS: Among the 7 patients, 2 had classic polyarteritis nodosa, one had unclassified systemic vasculitis, one had Wegener's granulomatosis (WG), and 3 had microscopic polyangiitis. The mean age of the patients was 70.2 years, and cranial symptoms revealed the disease in all but one patient. Temporal arteritis was generally associated with extracephalic manifestations suggestive of systemic vasculitis. Antineutrophilic cytoplasmic antibodies were positive in 3 of the 4 patients with small vessel vasculitis. Pathologically, the main temporal artery was involved in all but one patient, with inflammatory infiltrate of vasa vasorum and adventitia associated in 5 with small tributary involvement. Fibrinoid necrosis was rare, observed in 2 specimens; 2 patients with unclassified systemic vasculitis and WG had a classic giant cell arteritis (GCA) histologic pattern. Only one patient had exclusive involvement of small vessels, surrounding the spared main temporal artery. Muscle biopsies showed histopathological evidence of vasculitis in 2 patients, skin biopsy in one, and vein biopsy in the other. CONCLUSION: Temporal artery involvement in systemic necrotizing vasculitis was generally associated with extracranial clinical features suggestive of systemic vasculitis. Temporal artery biopsy is a simple tool for diagnosis of vasculitis, but the histopathological findings do not always discriminate between necrotizing vasculitis and classic GCA.     

Horton’s three sisters: familial clustering of temporal arteritis

The authors describe 3 histologically confirmed cases of temporal arteritis occurring in three siblings aged 62-72 years old, diagnosed from 1999 to 2005. Chapel Hill publication surrogate parameters combined with the American College of Rheumatology criteria for vasculitis were used in the diagnostic procedure. The diagnosis of temporal vasculitis was confirmed by right occipital artery excision and demonstration of relevant histopathology. Although genetic linkage studies have demonstrated a potential genetic predisposition to temporal arteritis, this is one of the rare multiple occurrences of temporal arteritis in a family reported in the literature.     

Diagnostic value of clinical signs in giant cell arteritis: analysis of 415 temporal artery biopsy findings

AIM OF THE STUDY: The American College of Rheumatology (ACR) has proposed a list of criteria for diagnosis of giant cell arteritis in order to guide clinical research by differentiating it from other vasculitis. The aim of this retrospective investigation, based on the findings of 415 temporal artery biopsies was to assess the diagnostic value of these criteria in the daily clinical setting. METHODS: The demographic, clinical and biological characteristics of patients with positive (confirmed cases of giant cell arteritis) or negative (controls) histopathological temporal artery biopsy findings were analyzed using downward step-by-step logistic regression analysis. This analysis enabled investigators to list signs with inherent diagnostic value. Based their odds-ratio, these factors were used to determine a clinical score for giant cell arteritis. RESULTS: A score of over 7 - out of a maximum score of 32 - enables the diagnosis for giant cell arteritis with the best possible compromise between a sensitivity of 75.7% and a specificity of 72.2%. ACR criteria had a sensitivity of 97.5% and a specificity of 78.9% when used in our patient group. CONCLUSION: Our study results are original in that the control group was composed of patients in whom the diagnosis of giant cell arteritis had been suggested but refuted by the absence of histopathological findings on the temporal artery biopsy. This pragmatic attitude in selecting the control group may explain the difference observed with the ACR criteria in terms of sensitivity and specificity. Further research is needed to develop a diagnostic method for giant cell arteritis without resorting to temporal artery biopsy.     

Coexistence of Takayasu’s arteritis and ankylosing spondylitis may not be accidental – Is there a need for a new subgroup in the spondyloarthritis family?

Aortitis of ascending aorta is a recognized complication of ankylosing spondylitis (AS). There are a few published cases of diffuse aortitis and aorta collaterals inflammation that fulfill Takayasu’s arteritis (TA) criteria coexisting with AS. We have reviewed published cases from literature and present three new cases of such coexistence. We identified three patients who fulfilled definite AS New York criteria in our Takayasu’s vasculitis cohort of eight patients. One of this patients had been diagnosed with Crohn’s disease before AS and TA diagnosis. Additionally, two other patients had an inflammatory back pain and suffered of chronic uveitis. One of them had increased sacroiliac uptake of isotope in scintigraphy. Those two patients did not fulfil spondyloarthritis criteria. In this paper, we debate if TA type arteritis might be one of the AS cardiovascular complications.     

Characteristics of cerebrovascular accidents at time of diagnosis in a series of 98 patients with giant cell arteritis

The objective of this study was to determine the characteristics of cerebrovascular accidents at time of diagnosis in patients with giant cell arteritis. Retrospective data were collected from 98 patients at a single hospital with giant cell arteritis (according to the American College of Rheumatology classification criteria) diagnosed between October 1999 and January 2012. Cerebrovascular accident was found at initial presentation in 6 patients (6.1 %, 95 % CIs 2.3–12.9). Most of them had other symptoms of giant cell arteritis when the disease began. Signs reflecting the involvement of vertebro-basilar territory were present in 3 cases. No other case of cerebrovascular accident was described during the follow-up of patient; particularly no case of cerebrovascular accident occurred once corticosteroid therapy for the treatment of giant cell arteritis had been initiated. No differences in the epidemiologic, clinical and laboratory features at the time of diagnosis between patients who had cerebrovascular accidents and the rest of the giant cell arteritis patients were observed. Prognosis was good in our survey. However, there was no case of bilateral vertebral artery occlusion, a condition associated with poor prognosis. The present study confirms that cerebrovascular accidents may be the initial manifestation of giant cell arteritis, an argument in favor of a direct effect of the vasculitis in the development of cerebrovascular accidents rather than a complication of the corticosteroid therapy. The diagnosis of giant cell arteritis should always be considered in an elderly patient with stroke and an unexplained elevation of inflammatory biomarkers.     

Silent,or masked,giant cell arteritis is associated with a strong inflammatory response and a benign short term course

OBJECTIVE: To determine the frequency, characteristics, and short term outcome of patients who have biopsy-proven giant cell arteritis (GCA) but no local symptoms that can be attributed to vasculitis inflammation [silent temporal arteritis (TA)] throughout the pretreatment course of the disease or an observational period lasting at least 2 months. METHODS: Of 175 consecutive patients with biopsy-proven GCA, 130 had typical cranial arteritis, 21 had silent vasculitis, and the remaining 24 had either discrete cranial symptoms (19 cases) or isolated extracranial vasculitis (5 cases). We sought to determine which of 15 pretreatment characteristics were associated with silent TA, as compared with typical cranial arteritis, and assessed the short term outcome in these patients. RESULTS: Of 21 patients with silent GCA, 14 met criteria for fever of unknown origin. Aside from their different clinical presentation, this population was characterized by a longer delay in diagnosis (p = 0.003), a higher mean erythrocyte sedimentation rate (p = 0.002), higher C-reactive protein (p = 0.002), and lower levels of albumin (p = 0.01) and hemoglobin (p < 0.0001). Permanent visual loss, which occurred in 24 patients (13.7%), exclusively involved those presenting with symptoms and/or signs suggesting cranial arteritis, especially those with frank cranial arteritis. This complication was associated negatively with the delay in diagnosis (p = 0.01), and marginally with the number of symptoms and/or signs suggesting cranial arteritis recorded in each patient (p = 0.07). Oral prednisone at a mean daily dose of 0.7 mg/kg resulted in satisfactory control of silent TA within 4 weeks in all patients but one, and could subsequently be safely tapered by half in a mean delay of 38 +/- 23 days. No differences were observed between patients with silent TA and other forms of the disease regarding the mean prednisone dose at 3 month followup (18.2 +/- 4.5 vs 20.9 +/- 5.9 mg/day) and 6 month followup (14 +/- 4.4 vs 15.6 +/- 6 mg/day ). CONCLUSION: Silent TA may represent a distinct subset of giant cell arteritis, marked by a protracted inflammatory response and a relatively benign short term outcome, excellent response to corticosteroids, and no visual ischemic events, despite the long period of exposure to this complication before appropriate treatment.     

Current Concept and Epidemiology of Systemic Vasculitides

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

The role of 2-18F-fluoro-2-deoxy-D-glucose positron emission tomography in the diagnosis of giant cell arteritis of the temporal arteries

OBJECTIVE: As one of the diagnostic criteria for giant cell arteritis affecting the temporal arteries (temporal arteritis) is still biopsy-proven vasculitis of the affected artery, the aim of our study was to evaluate the value of a non-invasive procedure, 2-(18)F-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (F-18-FDG-PET), in the diagnosis of Horton's disease. METHODS: During a period of 10 months, 22 consecutive patients with the clinical diagnosis of giant cell arteritis and a positive hypoechogenic halo in duplex sonography were re-examined with F-18-FDG-PET. Six patients had giant cell arteritis involving both the large arteries and the temporal arteries; five patients showed giant cell arteritis only in the large arteries without concomitant involvement of the temporal arteries, and the remaining 11 patients showed only involvement of the temporal arteries. All patients were examined by sonography and F-18-FDG-PET, which was performed before treatment with corticosteroids. RESULTS: All patients with positive signs of giant cell arteritis in duplex sonography, i.e. a hypoechogenic halo in the large arteries (thoracic, subclavian, axillary, iliac, aorta), also showed elevated FDG uptake in the same vessels, with complete agreement in the anatomical distribution of changes. When positive sonography was limited to the temporal arteries, FDG-PET was completely negative in the temporal arteries and all other arterial locations. CONCLUSION: PET is not yet suitable for the diagnosis of temporal arteritis and therefore cannot replace invasive biopsy. F-18-FDG-PET is well suited to the demonstration of giant cell arteritis in arteries exceeding 4 mm in diameter.     

F-18-fluorodeoxyglucose positron emission tomography in diagnosis and follow-up of patients with different types of vasculitis

BACKGROUND: F-18-fluorodeoxyglucose (FDG) accumulates in inflammatory cells due to an increased metabolic rate. Therefore, FDG positron emission tomography (PET) represents a promising imaging technique in patients with vasculitis. The aim of this study was to assess the value of FDG PET in the diagnosis of different types of vasculitis. METHODS: The results of FDG PET performed because of suspected vasculitis or fever of unknown origin with results indicating vasculitis were reviewed. These results were compared with the final diagnosis, based on the American College of Rheumatology 1990 criteria. RESULTS: FDG PET was ordered because of suspected vasculitis in 20 patients, because of fever of unknown origin in two patients, and for follow-up of vasculitis in five patients. Fourteen patients were diagnosed with vasculitis (giant cell arteritis n = 5, polymyalgia rheumatica n = 2, polyarteritis nodosa n = 3, Takayasu n = 1, Churge-Strauss n = 1, Wegener's granulomatosis n = 1, vasculitis skin n = 1), two patients were diagnosed with fibromuscular dysplasia and one patient had media necrosis of the aorta. In five patients no diagnosis could be reached. FDG PET results were considered to be true-positive in ten patients, true-negative in 14 patients and false-negative in three patients resulting in a positive predictive value of 100% and a negative predictive value of 82%. CONCLUSIONS: FDG PET appears to be a promising new imaging technique in diagnosing and determining the extent of various forms of vasculitis. Furthermore, FDG PET may become a useful tool for evaluating the effect of treatment of vasculitis.     

Demographic,Clinical, and Radiologic Characteristics of a Cohort of Patients with Takayasu Arteritis

BackgroundTakayasu arteritis is a rare large-vessel vasculitis that predominantly affects females of Asian descent. This retrospective analysis was performed to increase understanding of the epidemiology of the disease in the United States.MethodsWe performed a retrospective cohort study in 2 tertiary centers. Patients were selected according to the American College of Rheumatology classification criteria for Takayasu arteritis. Data collected included demographic characteristics and details of physical examinations, treatments, and surgical interventions. Data were managed with REDCap (Research Electronic Data Capture) tools.ResultsThe study included 57 patients. The female:male ratio was 4.2:1, the median age at diagnosis was 29 years, 61.4% of the patients were Caucasians, and 86% of the patients had stenosis on imaging. Hata V was the most common angiographic classification (37.5% of patients). Vascular interventions were required in 43.9% of patients. The most frequent complications were hypertension (56.1%), renal artery stenosis (28.1%), and aortic insufficiency (19.3%).ConclusionsTakayasu arteritis continues to be a rare large-vessel vasculitis. In the United States, it tends to affect predominantly Caucasian females, with cervicobrachial involvement. This cohort reflects the morbidity, multiple interventions, and complications experienced by patients with Takayasu arteritis.     

Use of ultrasonography and positron emission tomography in the diagnosis and assessment of large-vessel vasculitis

PURPOSE OF REVIEW: Ultrasonography and positron emission tomography have been increasingly studied and, in part, introduced in clinical practice to diagnose large-vessel vasculitides, such as temporal arteritis, Takayasu arteritis, large-vessel giant cell arteritis, and isolated aortitis. RECENT FINDINGS: Ultrasonography reveals characteristic homogenous, concentric wall thickening in vasculitis, often combined with stenoses and, less frequently, with acute occlusions. Thirteen studies describe sensitivities of 40 to 100% (median, 86%) for temporal artery vessel wall edema compared with histology, and of 35 to 86% (median, 70%) compared with clinical diagnosis. If wall edema, stenoses, and occlusions are included, sensitivities increase to 91 to 100% (median, 95%) compared with histology, and to 83 to 100% (median, 88%) compared with clinical diagnosis. Specificities for wall edema are 68 to 100% (median, 93%) compared with histology, and 78 to 100% (median, 97%) compared with clinical diagnosis. One should be aware of large-vessel giant cell arteritis in all patients with temporal arteritis and polymyalgia rheumatica. Ultrasonography reveals characteristic wall thickening, particularly of the distal subclavian, axillary, and proximal brachial arteries. Findings in Takayasu arteritis are similar, but the vessel wall swelling is usually brighter. Positron emission tomography reveals vasculitis in arteries with a diameter of more than 4 mm. Ultrasonography and positron emission tomography agreed completely in the anatomic distribution of changes in patients with large-vessel giant cell arteritis. It reveals asymptomatic large-vessel vasculitis in giant cell arteritis and Takayasu arteritis. Positron emission tomography is not suitable for the assessment of temporal arteries. SUMMARY: Ultrasonography and positron emission tomography are new, promising techniques to assess large-vessel vasculitides.     

Technology Insight: the role of color and power Doppler ultrasonography in rheumatology

An increasing number of rheumatologists have access to ultrasound equipment that provide both color and power Doppler modes, which can be used to investigate musculoskeletal and vascular pathologies. Musculoskeletal Doppler ultrasonography can be used to estimate levels of inflammation, to document the anti-inflammatory effect of agents such as corticosteroids and tumor necrosis factor inhibitors, to differentiate between inflammatory and degenerative disease, and to distinguish between normal and inflamed joints in cases of minor synovial swelling. Vascular Doppler ultrasonography can be used to determine organ involvement in small-vessel vasculitides, to delineate aneurysms in vasculitides of medium-sized arteries, and to assess the characteristic findings in large-vessel vasculitis. Numerous studies, including a meta-analysis, have been published on the use of temporal-artery ultrasonography for the diagnosis of giant cell arteritis. Duplex ultrasonography is a sensitive approach for detecting characteristic edematous wall swellings in active temporal arteritis and for assessing vasculitis of the axillary arteries (large-vessel giant cell arteritis) in patients with suspected temporal arteritis, polymyalgia rheumatica, or fever of unknown origin. Duplex ultrasonography can also be used to assess vasculitis of subclavian and carotid arteries in younger patients with Takayasu's arteritis and acute finger artery occlusions in patients with small-vessel vasculitides.     

A prospective study of vasculitis patients collected in a five year period: evaluation of the Chapel Hill nomenclature

OBJECTIVE: To test the usefulness of the Chapel Hill nomenclature, supplemented with surrogate parameters, as diagnostic criteria for primary vasculitides. METHODS: To prospectively evaluate vasculitis patients according to a standardised clinical and para-clinical programme. In accordance with the Chapel Hill publication surrogate parameters were used: proteinuria, haematuria and red blood cell casts (glomerulonephritis), angiographic or ultrasonic demonstration of aneurysms or stenoses (arteritis), radiological lung infiltrates or cavitations of more than one month's duration (granuloma in the lungs), bloody nasal discharge or crusts, chronic sinusitis, otitis and/or mastoiditis, bone and/or cartilage destruction, and acute hearing loss (granuloma in upper airways). RESULTS: The following entities were diagnosed: giant cell arteritis (n=14), Takayasu arteritis (n=1), polyarteritis nodosa (n=2), Wegener's granulomatosis (n=27), Churg-Strauss syndrome (n=2), microscopic polyangiitis (n=12), Henoch-Sch?nlein purpura (n=2), cutaneous leucocytoclastic angiitis (n=37), and secondary vasculitis (n=21). Giant cell arteritis and cutaneous leucocytoclastic angiitis were in all cases diagnosed by biopsy. Using the Chapel Hill nomenclature supplemented with surrogate parameters, only 8 of 27 patients were diagnosed with Wegener's granulomatosis, and 3 of 12 cases with microscopic polyangiitis. The number of patients in the remaining diagnostic entities were considered to few to evaluate. CONCLUSIONS: The Chapel Hill nomenclature, supplemented with surrogate parameters, failed to act as diagnostic criteria in Wegener's granulomatosis and microscopic polyangiitis. The following diagnostic criteria are proposed for Wegener's granulomatosis: (1) Biopsy or surrogate parameter for granulomatous inflammation in the respiratory system and (2) Biopsy verified necrotising vasculitis in small to medium sized vessels or biopsy/surrogate parameter for glomerulonephritis or positive PR3-ANCA test and (3) Lack of eosinophilia in blood and biopsy samples. The following diagnostic criteria are proposed for microscopic polyangiitis: (1) Biopsy verified necrotising vasculitis in small vessels and/or glomerulonephritis with few or no immune deposits and (2) Involvement of more than one organ system as indicated by biopsy verified vasculitis in small to medium sized vessels or surrogate parameter for glomerulonephritis and (3) Lack of biopsy and surrogate parameter for granulomatous inflammation in the respiratory system. Using these criteria all Wegener's patients and 9 of 12 patients with microscopic polyangiitis could be diagnosed.     

The American College of Rheumatology 1990 criteria for the classification of Henoch-Sch?nlein purpura

Criteria for identifying Henoch-Sch?nlein Purpura (HSP) and distinguishing HSP from other forms of systemic arteritis were developed by comparing the manifestations in 85 patients who had HSP with those of 722 control patients with other forms of vasculitis. By the traditional format of choosing different combinations of candidate criteria and comparing the combinations for their ability to separate HSP cases from controls, 4 criteria were identified: age less than or equal to 20 years at disease onset, palpable purpura, acute abdominal pain, and biopsy showing granulocytes in the walls of small arterioles or venules. The presence of any 2 or more of these criteria distinguish HSP from other forms of vasculitis with a sensitivity of 87.1% and a specificity of 87.7%. The criteria selected by a classification tree method were similar: palpable purpura, age less than or equal to 20 years at disease onset, biopsy showing granulocytes around arterioles or venules, and gastrointestinal bleeding. These were able to distinguish HSP from other forms of vasculitis with a sensitivity of 89.4% and a specificity of 88.1%.     

The American College of Rheumatology 1990 criteria for the classification of vasculitis. Patients and methods

The American College of Rheumatology Subcommittee on Classification of Vasculitis of the Diagnostic and Therapeutic Criteria Committee developed classification criteria for 7 forms of vasculitis: polyarteritis nodosa, Churg-Strauss syndrome, Wegener's granulomatosis, hypersensitivity vasculitis, Henoch-Sch?nlein purpura, giant cell (temporal) arteritis, and Takayasu arteritis. The data collection methods, quality control, and analytic procedures used to derive the classification rules are discussed herein.     

正电子发射计算机断层显像计算机断层扫描在系统性血管炎诊断及病情评估中的应用

系统性血管炎临床表现复杂,对于缺乏特征性表现者的诊断和病情严重程度评估,临床医生面临巨大的挑战。现有影像学检查手段对系统性血管炎的早期、活动性病变敏感性较低。正电子发射计算机断层显像与计算机断层扫描技术(positron emission tomographycomputed tomography,PETCT)对系统性血管炎中巨细胞动脉炎风湿性多肌痛、大动脉炎等大血管炎的诊断具有比较高的敏感新和特异性,特别是在疾病的早期和活动期,而对于中小血管受累的系统性血管炎并无太大帮助。通过PETCT可以全面了解系统性血管炎的解剖和功能定位,弥补其他影像学检查的不足。应注意在PETCT上系统性血管炎与其他血管疾病的鉴别。PETCT检查在系统性血管炎疗效评估中的作用尚有待进一步研究。     

Inflammatory disease in older adults. Cranial arteritis

Cranial arteritis (CA), also called giant cell arteritis or temporal arteritis, is a vasculitis primarily affecting adults over age 50. It is a large vessel vasculitis, and giant cells classically can be identified on histopathologic examination of temporal arteries, but are not essential for diagnosis. Patients typically present with severe headaches, fatigue, polymyalgia-like symptoms, or ischemic complaints such as jaw claudication. Visual loss is the major feared irreversible outcome and can occur in up to 50% of those with untreated disease. Glucocorticoids, typically high dose prednisone (> or = 60 mg/d) is the first-line treatment and successfully controls the inflammatory disease in the vast majority of patients. Most patients can be tapered off steroids within 6 months to 2 years.     

New arguments for a vasculitic nature of polymyalgia rheumatica using positron emission tomography.

OBJECTIVE: To study the possible contribution of fluorodeoxyglucose (FDG)-positron emission tomography (PET) in the diagnosis of giant cell arteritis and polymyalgia rheumatica. METHODS: A consecutive case series consisting of five patients with polymyalgia rheumatica, six patients with temporal arteritis and 23 age-matched patients with other inflammatory conditions were evaluated with FDG-PET. Studies were performed before therapy with steroids was started. RESULTS: A total of 4/6 patients with giant cell arteritis and 4/5 patients with polymyalgia had increased FDG uptake in their thoracic vessels, compared to 1/23 controls (P < 0.001). Increased vascular FDG uptake in the upper legs was seen in 8/11 patients with giant cell arteritis or polymyalgia compared to 8/23 control patients (P < 0.05), and in the lower legs in 6/11 patients compared to 6/23 controls (P = not significant). CONCLUSIONS: FDG-PET scan is the first non-invasive technique which may indicate large-vessel vasculitis and which can show its extension throughout the body. It strongly suggests that polymyalgia rheumatica is a form of vasculitis.