Khalidi, Nader

Abstract Objective To study the prevalence, risk and clinical associations of hypothyroidism among several forms of vasculitis. Methods Patients with GCA, Takayasu’s arteritis (TAK), PAN and the three forms of ANCA-associated vasculitis [AAV; granulomatosis with polyangiitis (GPA), microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis (EGPA)] enrolled in a prospective, multicentre, longitudinal study were included. Results The study included data on 2085 patients [63% female, 90% White] with a mean age of 54.6 years (s.d. 17.2). Diagnoses were GCA (20%), TAK (11%), PAN (5%), GPA (42%), microscopic polyangiitis (8%) and EGPA (14%). Hypothyroidism was present in 217 patients (10%) (83% female), with a mean age 59.8 years (s.d. 14.5). Age- and sex-adjusted risk of hypothyroidism was GCA, odds ratio (OR) 0.61 (95% CI 0.41, 0.90); TAK, OR 0.57 (95% CI 0.31, 1.03); PAN, OR 0.59 (95% CI 0.25, 1.38); GPA, OR 1.51 (95% CI 1.12, 2.05); microscopic polyangiitis, OR 1.81 (95% CI 1.18, 2.80) and EGPA, OR 0.82 (95% CI 0.52, 1.30). Among patients with AAV, age- and sex-adjusted risk of hypothyroidism was higher with positive MPO-ANCA [OR 1.89 (95% CI 1.39, 2.76)]. The clinical manifestations of vasculitis were similar in patients with and without hypothyroidism, except transient ischaemic attacks, which were more frequently observed in patients with GCA and hypothyroidism (12% vs 2%; P = 0.001). Conclusions Differences in the risk of hypothyroidism among vasculitides may be due to genetic susceptibilities or immune responses. This study confirms an association of hypothyroidism with MPO-ANCA.

ObjectiveTo describe clinical manifestations and outcomes in patients with eosinophilic granulomatosis with polyangiitis (EGPA) in North America.MethodsAnalysis of patients aged 18 years or older who fulfilled the 1990 American College of Rheumatology Classification Criteria for EGPA enrolled in the Vasculitis Clinical Research Consortium from 2003 to 2019. Main clinical characteristics, treatments, outcomes, and accumulated damage were studied.ResultsThe cohort included 354 patients; 59% female; age at diagnosis of 50.0 (±14) years; 39% were antineutrophil cytoplasm antibody (ANCA) positive. Time from diagnosis to last follow‐up was 7.0 (±6.2) years; 49.4% had one or more relapse. Patients positive for ANCA more commonly had neurological and kidney involvement when compared with patients negative for ANCA, who had more cardiac and lung manifestations. At last study visit, only 35 (12.6%) patients had been off all therapy for more than 2 years during their follow‐up. The overall mortality rate was 4.0% and did not differ by ANCA status or cyclophosphamide use. Scores on the Vasculitis Damage Index (VDI) for 134 patients with two or more visits and more than 1 year of follow‐up increased from 1.7 (±1.8) at enrollment (3.7 [±5.1] years after diagnosis) to 3.35 (±2.1) at last follow‐up (7.5 [±5.8] years after diagnosis), mainly represented by chronic asthma (67.5%), peripheral neuropathy (49.6%), and chronic sinusitis (31.3%). Longer duration of glucocorticoid use and relapse were associated with higher VDI scores.ConclusionThis analysis describes the many clinical manifestations and varied outcomes of EGPA and highlights the ongoing need to attain more sustained, long‐term remission to limit the accrual of disease‐related damage.

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.

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.

Abstract Objectives To describe tracheobronchial disease in patients with granulomatosis with polyangiitis (GPA) and evaluate the utility of dynamic expiratory CT to detect large-airway disease. Methods Demographic and clinical features associated with the presence of subglottic stenosis (SGS) or endobronchial involvement were assessed in a multicentre, observational cohort of patients with GPA. A subset of patients with GPA from a single-centre cohort underwent dynamic chest CT to evaluate the airways. Results Among 962 patients with GPA, SGS and endobronchial disease were identified in 95 (10%) and 59 (6%) patients, respectively. Patients with SGS were more likely to be female (72% vs 53%, P &lt; 0.01), younger at time of diagnosis (36 vs 49 years, P &lt; 0.01), and have saddle-nose deformities (28% vs 10%, P &lt; 0.01), but were less likely to have renal involvement (39% vs 62%, P &lt; 0.01). Patients with endobronchial disease were more likely to be PR3-ANCA positive (85% vs 66%, P &lt; 0.01), with more ENT involvement (97% vs 77%, P &lt; 0.01) and less renal involvement (42% vs 62%, P &lt; 0.01). Disease activity in patients with large-airway disease was commonly isolated to the subglottis/upper airway (57%) or bronchi (32%). Seven of 23 patients screened by dynamic chest CT had large-airway pathology, including four patients with chronic, unexplained cough, discovered to have tracheobronchomalacia. Conclusion SGS and endobronchial disease occur in 10% and 6% of patients with GPA, respectively, and may occur without disease activity in other organs. Dynamic expiratory chest CT is a potential non-invasive screening test for large-airway involvement in GPA.