Citations

ObjectiveDeficiency of adenosine deaminase 2 (DADA2) is a monogenic form of vasculitis that can resemble polyarteritis nodosa (PAN). This study was undertaken to identify potential disease‐causing sequence variants in ADA2 in patients with idiopathic PAN, granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA).MethodsPatients with idiopathic PAN (n = 118) and patients with GPA or MPA (n = 1,107) were screened for rare nonsynonymous variants in ADA2 using DNA sequencing methods. ADA‐2 enzyme activity was assessed in selected serum samples.ResultsNine of 118 patients with PAN (7.6%) were identified as having rare nonsynonymous variants in ADA2. Four patients (3.4%) were biallelic for pathogenic or likely pathogenic variants, and 5 patients (4.2%) were monoallelic carriers for 3 variants of uncertain significance and 2 likely pathogenic variants. Serum samples from 2 patients with PAN with biallelic variants were available and showed markedly reduced ADA‐2 enzyme activity. ADA‐2 enzyme testing of 86 additional patients revealed 1 individual with strongly reduced ADA‐2 activity without detectable pathogenic variants. Patients with PAN and biallelic variants in ADA2 were younger at diagnosis than patients with 1 or no variant in ADA2, with no other clinical differences noted. None of the patients with GPA or MPA carried biallelic variants in ADA2.ConclusionA subset of patients with idiopathic PAN meet genetic criteria for DADA2. Given that tumor necrosis factor inhibition is efficacious in DADA2 but is not conventional therapy for PAN, these findings suggest that ADA‐2 testing should strongly be considered in patients with hepatitis B virus–negative idiopathic PAN.

AbstractAn 80-year-old man presented with new-onset pain in the shoulders and lower extremities and elevated serum inflammatory markers. A clinical diagnosis of polymyalgia rheumatica (PMR) was made, but there was a suboptimal response to glucocorticoid therapy, prompting further evaluation. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) revealed intense FDG uptake in the arteries of the bilateral lower extremities, head, and neck, but sparing the aorta, suggestive of an uncommon pattern of giant cell arteritis (GCA). There were also imaging signs consistent with PMR, including FDG uptake in the synovium of large joints. This case highlights the uncommon manifestation of GCA with lower extremity involvement and sparing of the aorta. The combination of FDG PET imaging features and elevated serum markers obviated the need for invasive biopsy. One might also conclude that standard FDG PET/CT imaging protocols covering orbits/vertex to thighs incompletely evaluate the extent of arterial distribution of GCA.

Background Recent investigations suggest that inflammation and autoimmunity might have a role in the pathophysiology of atrial fibrillation (AF). Given that abnormal ventriculovascular coupling often coexists with AF, we hypothesize that autoimmune vasculitis plays a significant role in the pathogenetic mechanism of AF. Methods and Results A standardized retrospective population‐based case–control study was conducted to evaluate the association between autoimmune vasculitis and AF, and all‐cause mortality. The study included 8459 patients with a new diagnosis of AF and 8459 age‐, sex‐, and registration calendar year–matched controls in Olmsted County, Minnesota, between January 1, 1980 and December 31, 2010. The association of each clinical characteristic, diagnosis, and treatment was assessed using conditional logistic regression to account for the matched case–control study design. Cox proportional hazards regression models and Kaplan‐Meier curves were used to detect independent predictors of mortality and examine cumulative survival. Of a total of 16 918 patients (mean age 72.3+14.4 years; 48.7% women), 320 (1.9%) were diagnosed with autoimmune vasculitis before the index date during the 30‐year period. Among the cases, the prevalence of any autoimmune vasculitis was 2.3%, whereas the frequency of autoimmune vasculitis in controls was 1.5% ( P <0.001). After adjusting for potential confounders, the odds of autoimmune vasculitis in AF cases was 1.5 times higher than in controls (odds ratio, 1.47; 95% CI, 1.04–2.01; P =0.03). Patients with AF and autoimmune vasculitis had worse 5‐year survival than those without autoimmune vasculitis or AF (44.7% versus 77.2%; log‐rank P <0.001). Conclusions Autoimmune vasculitis is significantly associated with AF and independently confers worse survival. These observations may represent one mechanism linking autoimmunity and inflammation to the pathogenesis and prognosis of AF.

Significance Statement Efficacy of rituximab (RTX) in ANCA-associated vasculitis (AAV) in patients with severe renal involvement (eGFR<30 ml/min per 1.73 m 2 ) has not been addressed in clinical trials. This observational study did not find statistically significant differences between RTX and cyclophosphamide (CYC) for remission-induction therapy or any apparent benefit from the addition of plasma exchange (PLEX) to standard remission-induction therapy for patients with AAV and severe renal involvement. Although our analyses suggest that the benefits and risks of these therapeutic choices (RTX versus CYC with and without PLEX) are balanced, a randomized, controlled trial is needed to confirm these findings. Background Treatment of patients with ANCA-associated vasculitis (AAV) and severe renal involvement is not established. We describe outcomes in response to rituximab (RTX) versus cyclophosphamide (CYC) and plasma exchange (PLEX). Methods A retrospective cohort study of MPO- or PR3-ANCA–positive patients with AAV (MPA and GPA) and severe kidney disease (eGFR <30 ml/min per 1.73 m 2 ). Remission, relapse, ESKD and death after remission-induction with CYC or RTX, with or without the use of PLEX, were compared. Results Of 467 patients with active renal involvement, 251 had severe kidney disease. Patients received CYC ( n =161) or RTX ( n =64) for remission-induction, and 51 were also treated with PLEX. Predictors for ESKD and/or death at 18 months were eGFR <15 ml/min per 1.73 m 2 at diagnosis (IRR 3.09 [95% CI 1.49 to 6.40], P =0.002), renal recovery (IRR 0.27 [95% CI 0.12 to 0.64], P =0.003) and renal remission at 6 months (IRR 0.40 [95% CI 0.18 to 0.90], P =0.027). RTX was comparable to CYC in remission-induction (BVAS/WG=0) at 6 months (IRR 1.37 [95% CI 0.91 to 2.08], P =0.132). Addition of PLEX showed no benefit on remission-induction at 6 months (IRR 0.73 [95% CI 0.44 to 1.22], P =0.230), the rate of ESKD and/or death at 18 months (IRR 1.05 [95% CI 0.51 to 2.18], P =0.891), progression to ESKD (IRR 1.06 [95% CI 0.50 to 2.25], P =0.887), and survival at 24 months (IRR 0.54 [95% CI 0.16 to 1.85], P =0.330). Conclusions The apparent benefits and risks of using CYC or RTX for the treatment of patients with AAV and severe kidney disease are balanced. The addition of PLEX to standard remission-induction therapy showed no benefit in our cohort. A randomized controlled trial is the only satisfactory means to evaluate efficacy of remission-induction treatments in AAV with severe renal involvement.

ObjectiveGiant cell arteritis (GCA) is a large‐vessel vasculitis that primarily affects the aorta and its branches. Extracranial branches of the carotid artery are frequently affected; however, intracranial involvement in GCA is rare.MethodsA retrospective medical record review was performed to identify all patients with intracranial GCA (IC‐GCA) from January 1996 through May 2018.ResultsNine patients with IC‐GCA were included (78% male; mean age, 72.1 years [SD: 7.9]). All patients met ACR criteria for GCA. The median time from onset of GCA to intracranial involvement was 0.6 months (interquartile range: 0.1‐5.1). All patients had neurologic symptoms, 89% had an ischemic cerebrovascular event. Transient or permanent vision loss was frequent (56% of patients). IC‐GCA was diagnosed by cranial imaging in all nine patients. Intracranial vasculitis most commonly affected the internal carotid artery (100%), followed by the vertebral artery (67%), posterior cerebral artery (67%), middle cerebral artery (44%), anterior cerebral artery (33%), and posterior inferior cerebral artery (11%). Intracranial vessel stenosis was present in 89%, occlusion in 33%, wall thickening in 33%, and dilation in 11%.All patients received glucocorticoids. Additional therapeutic agents included cyclophosphamide (67%) and tocilizumab (22%). Despite treatment, five patients had rapid deterioration and mortality. Comparing IC‐GCA patient survival to the expected rates from the US population, the standardized mortality ratio (95% CI) for IC‐GCA was 58.1 (18.9‐135.6).ConclusionAlthough rare, IC‐GCA is associated with significant morbidity and mortality. It occurs predominantly in men and presents with ischemic cerebrovascular events. Current treatment strategies appear to be of limited efficacy for IC‐GCA.

AbstractObjectivesTo investigate metabolic features that may predispose to GCA in a nested case–control study.MethodsIndividuals who developed GCA after inclusion in a population-based health survey (the Malmö Preventive Medicine Project; N = 33 346) were identified and validated through a structured review of medical records. Four controls for every validated case were selected from the database.ResultsA total of 76 cases with a confirmed incident diagnosis of GCA (61% female, 65% biopsy positive, mean age at diagnosis 70 years) were identified. The median time from screening to diagnosis was 20.7 years (range 3.0–32.1). Cases had significantly lower fasting blood glucose (FBG) at baseline screening compared with controls [mean 4.7 vs 5.1 mmol/l (S.d. overall 1.5), odds ratio (OR) 0.35 per mmol/l (95% CI 0.17, 0.71)] and the association remained significant when adjusted for smoking [OR 0.33 per mmol/l (95% CI 0.16, 0.68)]. Current smokers had a reduced risk of GCA [OR 0.35 (95% CI 0.18, 0.70)]. Both cholesterol [mean 5.6 vs 6.0 mmol/l (S.d. overall 1.0)] and triglyceride levels [median 1.0 vs 1.2 mmol/l (S.d. overall 0.8)] were lower among the cases at baseline screening, with significant negative associations with subsequent GCA in crude and smoking-adjusted models [OR 0.62 per mmol/l (95% CI 0.43, 0.90) for cholesterol; 0.46 per mmol/l (95% CI 0.27, 0.81) for triglycerides].ConclusionDevelopment of GCA was associated with lower FBG and lower cholesterol and triglyceride levels at baseline, all adjusted for current smoking, suggesting that metabolic features predispose to GCA.

Objective To identify and validate, using computer‐driven methods, patterns of arterial disease in Takayasu arteritis (TAK) and giant cell arteritis (GCA). Methods Patients with TAK or GCA were studied from the Diagnostic and Classification Criteria for Vasculitis (DCVAS) cohort and a combined North American cohort. Case inclusion required evidence of large‐vessel involvement, defined as stenosis, occlusion, or aneurysm by angiography/ultrasonography, or increased 18 F‐fluorodeoxyglucose (FDG) uptake by positron emission tomography (PET) in at least 1 of 11 specified arterial territories. K‐means cluster analysis identified groups of patients based on the pattern of arterial involvement. Cluster groups were identified in the DCVAS cohort and independently validated in the North American cohort. Results A total of 1,068 patients were included (DCVAS cohort: TAK = 461, GCA = 217; North American cohort: TAK = 225, GCA = 165). Six distinct clusters of patients were identified in DCVAS and validated in the North American cohort. Patients with TAK were more likely to have disease in the abdominal vasculature, bilateral disease of the subclavian and carotid arteries, or focal disease limited to the left subclavian artery than GCA ( P < 0.01). Patients with GCA were more likely to have diffuse disease, involvement of bilateral axillary/subclavian arteries, or minimal disease without a definable pattern than TAK ( P < 0.01). Patients with TAK were more likely to have damage by angiography, and patients with GCA were more likely to have arterial FDG uptake by PET without associated vascular damage. Conclusion Arterial patterns of disease highlight both shared and divergent vascular patterns between TAK and GCA and should be incorporated into classification criteria for large‐vessel vasculitis.

Abstract Objectives To develop and replicate, using data-driven methods, a novel classification system in Takayasu’s arteritis based on distribution of arterial lesions. Methods Patients were included from four international cohorts at major academic centres: India (Christian Medical College Vellore); North America (National Institutes of Health, Vasculitis Clinical Research Consortium and Cleveland Clinic Foundation). All patients underwent whole-body angiography of the aorta and branch vessels, with categorization of arterial damage (stenosis, occlusion or aneurysm) in 13 territories. K-means cluster analysis was performed to identify subgroups of patients based on pattern of angiographic involvement. Cluster groups were identified in the Indian cohort and independently replicated in the North American cohorts. Results A total of 806 patients with Takayasu’s arteritis from India (n = 581) and North America (n = 225) were included. Three distinct clusters defined by arterial damage were identified in the Indian cohort and replicated in each of the North American cohorts. Patients in cluster one had significantly more disease in the abdominal aorta, renal and mesenteric arteries (P &lt; 0.01). Patients in cluster two had significantly more bilateral disease in the carotid and subclavian arteries (P &lt; 0.01). Compared with clusters one and two, patients in cluster three had asymmetric disease with fewer involved territories (P &lt; 0.01). Demographics, clinical symptoms and clinical outcomes differed by cluster. Conclusion This large study in Takayasu’s arteritis identified and replicated three novel subsets of patients based on patterns of arterial damage. Angiographic-based disease classification requires validation by demonstrating potential aetiological or prognostic implications.