Plasma Exchange and Glucocorticoids in Severe ANCA-Associated Vasculitis.

BACKGROUND: More effective and safer treatments are needed for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. METHODS: We conducted a randomized trial with a 2-by-2 factorial design to evaluate the use of plasma exchange and two regimens of oral glucocorticoids in patients with severe ANCA-associated vasculitis (defined by an estimated glomerular filtration rate of <50 ml per minute per 1.73 m2 of body-surface area or diffuse pulmonary hemorrhage). Patients were randomly assigned to undergo plasma exchange (seven plasma exchanges within 14 days after randomization) or no plasma exchange (control group). Patients were also randomly assigned to follow either a standard-dose regimen or a reduced-dose regimen of oral glucocorticoids. Patients were followed for up to 7 years for the primary composite outcome of death from any cause or end-stage kidney disease (ESKD). RESULTS: Death from any cause or ESKD occurred in 100 of 352 patients (28.4%) in the plasma-exchange group and in 109 of 352 patients (31.0%) in the control group (hazard ratio, 0.86; 95% confidence interval [CI], 0.65 to 1.13; P = 0.27). The results were similar in subgroup analyses and in analyses of secondary outcomes. We also assessed the noninferiority of a reduced-dose regimen of glucocorticoids to a standard-dose regimen, using a noninferiority margin of 11 percentage points. Death from any cause or ESKD occurred in 92 of 330 patients (27.9%) in the reduced-dose group and in 83 of 325 patients (25.5%) in the standard-dose group (absolute risk difference, 2.3 percentage points; 90% CI, -3.4 to 8.0), which met the criterion for noninferiority. Serious infections at 1 year were less common in the reduced-dose group than in the standard-dose group (incidence rate ratio, 0.69; 95% CI, 0.52 to 0.93), but other secondary outcomes were similar in the two groups. CONCLUSIONS: Among patients with severe ANCA-associated vasculitis, the use of plasma exchange did not reduce the incidence of death or ESKD. A reduced-dose regimen of glucocorticoids was noninferior to a standard-dose regimen with respect to death or ESKD. (Funded by the U.K. National Institute for Health Research and others; PEXIVAS Current Controlled Trials number, ISRCTN07757494; ClinicalTrials.gov number, NCT00987389.).

Rituximab versus azathioprine for maintenance of remission for patients with ANCA-associated vasculitis and relapsing disease: an international randomised controlled trial.

OBJECTIVE: Following induction of remission with rituximab in anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) relapse rates are high, especially in patients with history of relapse. Relapses are associated with increased exposure to immunosuppressive medications, the accrual of damage and increased morbidity and mortality. The RITAZAREM trial compared the efficacy of repeat-dose rituximab to daily oral azathioprine for prevention of relapse in patients with relapsing AAV in whom remission was reinduced with rituximab. METHODS: RITAZAREM was an international randomised controlled, open-label, superiority trial that recruited 188 patients at the time of an AAV relapse from 29 centres in seven countries between April 2013 and November 2016. All patients received rituximab and glucocorticoids to reinduce remission. Patients achieving remission by 4 months were randomised to receive rituximab intravenously (1000 mg every 4 months, through month 20) (85 patients) or azathioprine (2 mg/kg/day, tapered after month 24) (85 patients) and followed for a minimum of 36 months. The primary outcome was time to disease relapse (either major or minor relapse). RESULTS: Rituximab was superior to azathioprine in preventing relapse: HR 0.41; 95% CI 0.27 to 0.61, p<0.001. 19/85 (22%) patients in the rituximab group and 31/85 (36%) in the azathioprine group experienced at least one serious adverse event during the treatment period. There were no differences in rates of hypogammaglobulinaemia or infection between groups. CONCLUSIONS: Following induction of remission with rituximab, fixed-interval, repeat-dose rituximab was superior to azathioprine for preventing disease relapse in patients with AAV with a prior history of relapse. TRIAL REGISTRATION NUMBER: NCT01697267; ClinicalTrials.gov identifier.

Hypothyroidism in vasculitis.

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.

Assessment of glucocorticoid tapering in large vessel and anti-neutrophil cytoplasmic antibody-associated vasculitides.

OBJECTIVES: Glucocorticoids (GC) remain integral to large vessel vasculitis (LVV) and ANCA-associated vasculitis (AAV) treatment. We aimed to assess real-world GC tapering trajectories among patients referred for LVV or AAV and identify factors associated with 'delayed' tapering. METHODS: Patients first assessed at a vasculitis clinic July 2017-August 2019 for LVV or AAV and taking GC were included. Delayed tapering was defined as prednisone >10 mg above target based on tapering recommendations (2010 British Society of Rheumatology Guidelines for Giant Cell Arteritis, 2015 CanVasc AAV Recommendations). We compared characteristics of patients with delayed and appropriate tapering and assessed barriers to timely tapering though chart reviews and referring physician surveys. RESULTS: 160 patients (65 LVV, 95 AAV) were taking GC at their first visit. Among the 42 (26%) patients with delayed tapering, mean daily prednisone dose was 39.2 mg (SD 14) compared to a target of 15.2 mg (SD 15). Pulse GC were administered to 19/42 (45%) patients with delayed tapering compared to 26/118 (22%) with appropriate tapering (p<0.05). Mean Birmingham Vasculitis Activity Score at treatment onset and GC duration were not significantly different between the two groups. Vision loss and/or stroke was more frequent in LVV referrals who experienced delayed (9/21, 43%) vs. appropriate (6/44, 14%) tapering (p<0.05). Managing risk of vasculitis flare was the most common challenge to tapering GC among surveyed referring physicians. CONCLUSIONS: In one quarter of patients referred for LVV or AAV taking GC, tapering was slower than recommended. Promoting timely tapering may reduce GC toxicity.

Efficacy of leflunomide in the treatment of vasculitis.

OBJECTIVES: Only a few small case series, case reports, and one small clinical trial suggested some benefit of leflunomide (LEF) in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis and other vasculitides. We analysed the clinical efficacy and tolerability of LEF in a large cohort of patients with various vasculitides. METHODS: This was a retrospective analysis of patients who received LEF for treatment of their vasculitis enrolled in the Vasculitis Clinical Research Consortium (VCRC) Longitudinal Study and in 3 additional centres from the Canadian vasculitis research network (CanVasc). RESULTS: Data for 93 patients were analysed: 45 had granulomatosis with polyangiitis (GPA), 8 microscopic polyangiitis (MPA), 12 eosinophilic granulomatosis with polyangiitis (EGPA), 14 giant-cell arteritis (GCA), 9 Takayasu's arteritis (TAK), and 5 polyarteritis nodosa (PAN). The main reason for initiation of LEF was active disease (89%). LEF was efficacious for remission induction or maintenance at 6 months for 62 (67%) patients (64% with GCA, 89% with TAK, 80% with PAN, 69% with GPA, 75% with MPA, 33% with EGPA); 20% discontinued LEF before achieving remission because of persistent disease activity. Overall, 22 adverse events (gastrointestinal symptoms being the most common) led to drug discontinuation in 18 (19%) patients, of which 12 stopped LEF before month 6, before showing any benefit in 8/12 of these patients. CONCLUSIONS: Leflunomide can be an effective therapeutic option for various vasculitides, especially for non-severe refractory or relapsing ANCA-associated vasculitis or large-vessel vasculitis. No new safety signals for LEF were identified in this population.

An Initiative to Improve Timely Glucocorticoid Tapering in Vasculitis.

BACKGROUND/OBJECTIVE: High-dose glucocorticoids (GCs) are required in the initial treatment of systemic vasculitis. However, slow or delayed tapering can lead to unnecessary GC exposure and toxicity. In this quality improvement initiative, we aimed to increase appropriate GC tapering among newly referred patients awaiting specialty consultation at a tertiary vasculitis clinic. METHODS: For each patient referred for anti-neutrophil cytoplasm antibody-associated vasculitis (AAV) or large vessel vasculitis (LVV), recommendation-based GC tapering suggestions were faxed to referring physicians. To maximize uptake, the intervention format was modified according to feedback from referring physicians' offices. The proportion of new patients presenting to their first appointment who (1) had started to taper GCs, (2) were taking their target GC dose according to recommendations, (3) experienced a vasculitis flare during tapering were compared before (July 2017-January 2019) and after (February-October 2019) the intervention. RESULTS: Among 169 consecutive patients referred for AAV or LVV, the proportion who had started to taper GCs by their first visit increased from 84 of 117 (72%) preintervention to 49 of 52 (94%) postintervention (p < 0.01). Mean daily prednisone dose at first visit decreased from 29.9 (SD, 18) mg to 21.7 (SD, 14) mg (p < 0.01). However, the proportion who were ultimately taking "target" GC doses at their first visit did not significantly increase (72% vs. 77%). Disease flares during tapering were similar before and after the intervention (9% vs. 12%). CONCLUSIONS: Patients with AAV and LVV had increased GC tapering and lower GC doses at first visit following a preappointment intervention. Further strategies are needed to improve timely GC tapering in vasculitis.

Rituximab as therapy to induce remission after relapse in ANCA-associated vasculitis.

OBJECTIVES: Evaluation of rituximab and glucocorticoids as therapy to induce remission after relapse in ANCA-associated vasculitis (AAV) in a prospective observational cohort of patients enrolled into the induction phase of the RITAZAREM trial. METHODS: Patients relapsing with granulomatosis with polyangiitis or microscopic polyangiitis were prospectively enrolled and received remission-induction therapy with rituximab (4×375 mg/m2) and a higher or lower dose glucocorticoid regimen, depending on physician choice: reducing from either 1 mg/kg/day or 0.5 mg/kg/day to 10 mg/day by 4 months. Patients in this cohort achieving remission were subsequently randomised to receive one of two regimens to prevent relapse. RESULTS: 188 patients were studied: 95/188 (51%) men, median age 59 years (range 19-89), prior disease duration 5.0 years (range 0.4-34.5). 149/188 (79%) had previously received cyclophosphamide and 67/188 (36%) rituximab. 119/188 (63%) of relapses had at least one major disease activity item, and 54/188 (29%) received the higher dose glucocorticoid regimen. 171/188 (90%) patients achieved remission by 4 months. Only six patients (3.2% of the study population) did not achieve disease control at month 4. Four patients died in the induction phase due to pneumonia (2), cerebrovascular accident (1), and active vasculitis (1). 41 severe adverse events occurred in 27 patients, including 13 severe infections. CONCLUSIONS: This large prospective cohort of patients with relapsing AAV treated with rituximab in conjunction with glucocorticoids demonstrated a high level of efficacy for the reinduction of remission in patients with AAV who have relapsed, with a similar safety profile to previous studies.

Derivation of an angiographically based classification system in Takayasu's arteritis: an observational study from India and North America.

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 < 0.01). Patients in cluster two had significantly more bilateral disease in the carotid and subclavian arteries (P < 0.01). Compared with clusters one and two, patients in cluster three had asymmetric disease with fewer involved territories (P < 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.

Urinary soluble CD163 and monocyte chemoattractant protein-1 in the identification of subtle renal flare in anti-neutrophil cytoplasmic antibody-associated vasculitis.

BACKGROUND: Prior work has shown that urinary soluble CD163 (usCD163) displays excellent biomarker characteristics for detection of active renal vasculitis using samples that included new diagnoses with highly active renal disease. This study focused on the use of usCD163 in the detection of the more clinically relevant state of mild renal flare and compared results of usCD163 testing directly to testing of urinary monocyte chemoattractant protein-1 (uMCP-1). METHODS: Patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV, n = 88) were identified within a serially sampled, longitudinal and multicentre cohort. Creatinine-normalized usCD163 and uMCP-1 levels were measured by enzyme-linked immunosorbent assay and, both alone and in combination, were compared between times of active renal AAV and during remission and/or active non-renal AAV. RESULTS: Samples from 320 study visits included times of active renal vasculitis (n = 39), remission (n = 233) and active extrarenal vasculitis (n = 48). Median creatinine levels were 0.9 mg/dL [interquartile range (IQR) 0.8-1.2] in remission and 1.4 mg/dL (IQR 1.0-1.8) during renal flare. usCD163 levels were higher in patients with active renal vasculitis compared with patients in remission and those with active extrarenal vasculitis, with median values of 162 ng/mmol (IQR 79-337), 44 (17-104) and 38 (7-76), respectively (P < 0.001). uMCP-1 levels were also higher in patients with active renal vasculitis compared with patients in remission and those with active extrarenal vasculitis, with median values of 10.6 pg/mmol (IQR 4.6-23.5), 4.1 (2.5-8.4) and 4.1 (1.9-6.8), respectively (P < 0.001). The proposed diagnostic cut-points for usCD163 and uMCP-1 were 72.9 ng/mmol and 10.0 pg/mmol, respectively. usCD163 and uMCP-1 levels were marginally correlated (r2 = 0.11, P < 0.001). Combining novel and existing biomarkers using recursive tree partitioning indicated that elevated usCD163 plus either elevated uMCP-1 or new/worse proteinuria improved the positive likelihood ratio (PLR) of active renal vasculitis to 19.2. CONCLUSION: A combination of usCD163 and uMCP-1 measurements appears to be useful in identifying the diagnosis of subtle renal vasculitis flare.

Efficacy of conventional immunosuppressants in relapsing or refractory eosinophilic granulomatosis with polyangiitis: evidence from a Canadian single-centre cohort.

OBJECTIVES: To describe the efficacy of conventional immunosuppressants in disease control of relapsing or refractory eosinophilic granulomatosis with polyangiitis (EGPA) compared to recently published mepolizumab and rituximab studies. METHODS: A retrospective analysis from the Toronto Vasculitis Clinic was conducted. Patients with relapsing or refractory EGPA with similar entry criteria as the main mepolizumab (MIRRA) or rituximab (case-series) studies, who were started on conventional immunosuppressants, were assessed for remission at 24- and 52-weeks. Remission was defined as a Birmingham Vasculitis Activity Score of 0 and a prednisone dose of ≤4mg/day, ≤7.5mg/day, corresponding to the mepolizumab trial, or any prednisone dose per day, as in the rituximab study. RESULTS: Among 110 cohort patients, 24 with relapsing or refractory EGPA met eligibility criteria. Conventional immunosuppressants used were methotrexate (n=15), azathioprine (n=8) or leflunomide (n=1). Remission rates at 24-weeks were 8.3% with prednisone ≤4mg/day (vs. 28.0% in the mepolizumab trial); 41.6% with prednisone ≤7.5mg/day (vs. 45% in the mepolizumab trial) and 62.5% with any prednisone dose (vs. 34% in the rituximab study). Remission at 52-weeks was 50.0% with any prednisone dose (vs. 49% in the rituximab study), whereas sustained remission at week 52 (as of week 24) was 4.2% with prednisone ≤4mg/day (vs. 19% in the mepolizumab trial), and 33.3% with prednisone ≤7.5mg/day (vs. 24% in the mepolizumab trial). CONCLUSIONS: Though our study was small and retrospective, rates of remission observed with conventional immunosuppressants were substantial. This should be kept in mind when interpreting results of placebo-controlled or retrospective studies on biologics in EGPA.

Subglottic stenosis and endobronchial disease in granulomatosis with polyangiitis.

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 < 0.01), younger at time of diagnosis (36 vs 49 years, P < 0.01), and have saddle-nose deformities (28% vs 10%, P < 0.01), but were less likely to have renal involvement (39% vs 62%, P < 0.01). Patients with endobronchial disease were more likely to be PR3-ANCA positive (85% vs 66%, P < 0.01), with more ENT involvement (97% vs 77%, P < 0.01) and less renal involvement (42% vs 62%, P < 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.

Serum cytokine and chemokine levels in patients with eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome, or eosinophilic asthma.

OBJECTIVES: The pathogenesis of eosinophilic granulomatosis with polyangiitis (EGPA) remains poorly understood, and may overlap with eosinophilic asthma and primary hypereosinophilic syndrome (HES). The aim of this study was to analyse a panel of serum cytokines and chemokines as markers of disease activity in patients with these conditions. METHODS: The levels of 54 cytokines and chemokines were measured in the sera of 40 patients with active EGPA, 10 of these patients during inactive disease, 6 patients with HES, 8 with asthma, and 10 healthy controls. Serum cytokine/chemokines measured included interleukin (IL)-1α, 1ß, 3, 4, 5, 6, 8, 13, 15, 17A, 17E(25), 18, 23 and 33, soluble IL-2 receptor alpha, eotaxin-1 (CCL11), -2 (CCL24) and -3 (CCL26), macrophage-derived chemokine (MDC/CCL22), macrophage inflammatory protein (MIP)-1a and -1b, and tumour necrosis factor (TNF)-α. Results were compared between disease and control groups using regression analysis, with Bonferroni correction for multiple comparisons (significant p value ≤0.00093). RESULTS: Significant differences were observed only in serum levels of MDC, IL-8, MIP-1a and -1b, TNF-α, each of which were lower in patients with active EGPA than in healthy controls (p<0.0001). Differences between patients with active disease and other disease groups did not reach significance. Paired comparisons between sera from patients with active or inactive EGPA showed no significant difference for any of the studied cytokines or chemokines. CONCLUSIONS: No clear difference in the serum levels of measured cytokines and chemokines helped distinguish between active EGPA or inactive EGPA, or other disease or control groups.

A large-scale genetic analysis reveals a strong contribution of the HLA class II region to giant cell arteritis susceptibility.

We conducted a large-scale genetic analysis on giant cell arteritis (GCA), a polygenic immune-mediated vasculitis. A case-control cohort, comprising 1,651 case subjects with GCA and 15,306 unrelated control subjects from six different countries of European ancestry, was genotyped by the Immunochip array. We also imputed HLA data with a previously validated imputation method to perform a more comprehensive analysis of this genomic region. The strongest association signals were observed in the HLA region, with rs477515 representing the highest peak (p = 4.05 × 10(-40), OR = 1.73). A multivariate model including class II amino acids of HLA-DRß1 and HLA-DQα1 and one class I amino acid of HLA-B explained most of the HLA association with GCA, consistent with previously reported associations of classical HLA alleles like HLA-DRB1(∗)04. An omnibus test on polymorphic amino acid positions highlighted DRß1 13 (p = 4.08 × 10(-43)) and HLA-DQα1 47 (p = 4.02 × 10(-46)), 56, and 76 (both p = 1.84 × 10(-45)) as relevant positions for disease susceptibility. Outside the HLA region, the most significant loci included PTPN22 (rs2476601, p = 1.73 × 10(-6), OR = 1.38), LRRC32 (rs10160518, p = 4.39 × 10(-6), OR = 1.20), and REL (rs115674477, p = 1.10 × 10(-5), OR = 1.63). Our study provides evidence of a strong contribution of HLA class I and II molecules to susceptibility to GCA. In the non-HLA region, we confirmed a key role for the functional PTPN22 rs2476601 variant and proposed other putative risk loci for GCA involved in Th1, Th17, and Treg cell function.

Evaluation of damage in giant cell arteritis.

Objectives: To evaluate damage and variables associated with damage in GCA. Methods: Patients with GCA enrolled in a prospective, multicentre, longitudinal study were included. Per-protocol assessments were made with the Vasculitis Damage Index and the Large-Vessel Vasculitis Index of Damage. Results: The study included 204 patients: 156 women (76%), mean age at diagnosis 71.3 years (s.d. 8.3), mean follow-up of 3.5 years (s.d. 1.9). One or more damage item was present in 54% at baseline and 79% at the last follow-up on the Vasculitis Damage Index, and 60% at baseline and 82% at the last follow-up on the Large-Vessel Vasculitis Index of Damage. The most frequently observed damage items were large-artery complications (29% cohort) and ocular (22%). Among 117 patients with new damage, most new items were ocular (63 patients), cardiac/vascular (48) and musculoskeletal (34). Of these, treatment-associated items were frequently observed, including cataracts (46 patients), osteoporosis (22) and weight gain (22). Disease-associated new damage included ischaemic optic neuropathy (3 patients), limb claudication (13), arterial occlusions (10) and damage requiring vascular intervention (10). In univariate analysis, the risk of damage increased 22% for every additional year of disease duration [odds ratio (OR) 1.22 (95% CI 1.04, 1.45)]. In 94 patients enrolled within ⩽90 days of diagnosis of GCA, the risk of new damage at the last follow-up decreased 30% for each additional relapse [OR 0.70 (95% CI 0.51, 0.97)]. Conclusions: Large-artery complications and ocular manifestations are the most commonly occurring items of damage in GCA. Most new damage is associated with treatment. These findings emphasize the cumulative burden of disease in GCA.

IgA antibodies to myeloperoxidase in patients with eosinophilic granulomatosis with polyangiitis (Churg-Strauss).

OBJECTIVES: To determine the prevalence of anti-myeloperoxidase (MPO) antibodies of IgA (IgA anti-MPO) isotype in patients with eosinophilic granulomatosis with polyangiitis (EGPA), and the association of the IgA antibodies with IgG anti-MPO and with disease activity. METHODS: Serum samples from patients with EGPA followed in a multicenter longitudinal cohort were tested by ELISA for the presence of IgA anti-MPO and IgG anti-MPO antibodies. Sera from 87 healthy controls were used to define a positive test. Sera from 168 patients with EGPA (298 samples) were tested. Frequencies of positive testing for IgA anti-MPO were compared between patients with active EGPA, patients in remission, and controls. RESULTS: IgA anti-MPO was detected in 10 of 168 (6%) patients with EGPA (11 of 298 serum samples) compared to 1 of 87 (1%) healthy controls (p=0.10). All 11 samples testing positive for IgA anti-MPO also tested positive for IgG anti-MPO. Ninety samples tested positive for IgG anti-MPO but negative for IgA. Samples taken during active EGPA were positive for IgA anti-MPO in 6/72 cases (8%), compared to 5/226 (2%) during remission (p=0.03). Among samples taken during moderate or high disease activity, 5/41 were positive (12%, p=0.01 compared to remission). CONCLUSIONS: Although IgA anti-MPO antibodies are detectable in some patients with EGPA and may be detectable more frequently during active disease, their presence seems unlikely to provide information beyond what is obtained from conventional IgG anti-MPO.

Experience With Direct-to-Patient Recruitment for Enrollment Into a Clinical Trial in a Rare Disease: A Web-Based Study.

BACKGROUND: The target sample size for clinical trials often necessitates a multicenter (center of excellence, CoE) approach with associated added complexity, cost, and regulatory requirements. Alternative recruitment strategies need to be tested against this standard model. OBJECTIVES: The aim of our study was to test whether a Web-based direct recruitment approach (patient-centric, PC) using social marketing strategies provides a viable option to the CoE recruitment method. METHODS: PC recruitment and Web-based informed consent was compared with CoE recruitment for a randomized controlled trial (RCT) of continuing versus stopping low-dose prednisone for maintenance of remission of patients with granulomatosis with polyangiitis (GPA). RESULTS: The PC approach was not as successful as the CoE approach. Enrollment of those confirmed eligible by their physician was 10 of 13 (77%) and 49 of 51 (96%) in the PC and CoE arms, respectively (P=.05). The two approaches were not significantly different in terms of eligibility with 34% of potential participants in the CoE found to be ineligible as compared with 22% in the PC arm (P=.11) nor in provider acceptance, 22% versus 26% (P=.78). There was no difference in the understanding of the trial as reflected in the knowledge surveys of individuals in the PC and CoE arms. CONCLUSIONS: PC recruitment was substantially less successful than that achieved by the CoE approach. However, the PC approach was good at confirming eligibility and was as acceptable to providers and as understandable to patients as the CoE approach. The PC approach should be evaluated in other clinical settings to get a better sense of its potential.

Identification of multiple genetic susceptibility loci in Takayasu arteritis.

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B*52. We genotyped ~200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r(2) < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10(-16)) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10(-9); and rs189754752, OR = 2.47, p = 4.22 × 10(-9)). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10(-12)). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10(-8)).

Value of commonly measured laboratory tests as biomarkers of disease activity and predictors of relapse in eosinophilic granulomatosis with polyangiitis.

OBJECTIVE: The aim of this study was to assess the clinical value of absolute eosinophil count, serum IgE, ESR and CRP as longitudinal biomarkers of disease activity and predictors of relapse in eosinophilic granulomatosis with polyangiitis (Churg-Strauss, EGPA). METHODS: Patients were selected from an observational EGPA cohort. Absolute eosinophil count, IgE, ESR and CRP were measured quarterly. Disease activity was defined by validated assessment tools. The association of tests with disease activity was assessed via regression models, adjusting for repeated measures and treatment status. Survival analysis was used to determine if laboratory tests were predictive of the 3 month future flare risk. RESULTS: Seventy-four per cent of 892 study visits in 141 patients occurred while patients were on treatment, mostly during remission or mild disease activity, defined as a BVAS for Wegener's granulomatosis (BVAS/WG) of 1 or 2. Correlations between absolute eosinophil count, IgE, ESR and CRP were mostly low or non-significant (r = -0.08 to 0.44). There were few weak associations with disease activity [absolute eosinophil count: OR) 1.01/100 U (95% CI 1.01, 1.02); ESR: OR 1.15/10 mg/l increase (95% CI 1.04, 1.27)]. When BVAS/WG ≥1 defined active disease, the absolute eosinophil count [hazard ratio (HR) 1.01/100 U (95% CI 1.01, 1.02)] was weakly predictive of flare. When BVAS/WG ≥3 defined active disease, ESR was weakly predictive of flare [HR 1.52/10 mm/h increase (95% CI 1.17, 1.67)]. CONCLUSION: The absolute eosinophil count, IgE, ESR and CRP have limitations as longitudinal biomarkers of disease activity or predictors of flare in EGPA. These findings suggest that novel biomarkers of disease activity for EGPA are needed.

Association of granulomatosis with polyangiitis (Wegener's) with HLA-DPB1*04 and SEMA6A gene variants: evidence from genome-wide analysis.

OBJECTIVE: To identify genetic determinants of granulomatosis with polyangiitis (Wegener's) (GPA). METHODS: We carried out a genome-wide association study (GWAS) of 492 GPA cases and 1,506 healthy controls (white subjects of European descent), followed by replication analysis of the most strongly associated signals in an independent cohort of 528 GPA cases and 1,228 controls. RESULTS: Genome-wide significant associations were identified in 32 single-nucleotide polymorphic (SNP) markers across the HLA region, the majority of which were located in the HLA-DPB1 and HLA-DPA1 genes encoding the class II major histocompatibility complex (MHC) DPß chain 1 and DPα chain 1 proteins, respectively. Peak association signals in these 2 genes, emanating from SNPs rs9277554 (for DPß chain 1) and rs9277341 (DPα chain 1) were strongly replicated in an independent cohort (in the combined analysis of the initial cohort and the replication cohort, P = 1.92 × 10(-50) and 2.18 × 10(-39) , respectively). Imputation of classic HLA alleles and conditional analyses revealed that the SNP association signal was fully accounted for by the classic HLA-DPB1*04 allele. An independent single SNP, rs26595, near SEMA6A (the gene for semaphorin 6A) on chromosome 5, was also associated with GPA, reaching genome-wide significance in a combined analysis of the GWAS and replication cohorts (P = 2.09 × 10(-8) ). CONCLUSION: We identified the SEMA6A and HLA-DP loci as significant contributors to risk for GPA, with the HLA-DPB1*04 allele almost completely accounting for the MHC association. These two associations confirm the critical role of immunogenetic factors in the development of GPA.