Muscle biopsy in anti-neutrophil cytoplasmic antibody-associated vasculitis: diagnostic yield depends on anti-neutrophil cytoplasmic antibody type, sex and neutrophil count.

OBJECTIVES: This study aimed to examine the sensitivity of muscle biopsy (MB) in ANCA-associated vasculitis (AAV), identify factors predicting MB positivity and assess the prognostic value of a positive MB. METHODS: We conducted a single-centre retrospective study of AAV with an MB performed at diagnosis. AAV classification [granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA)] followed the European Medicines Agency algorithm. A logistic regression model was used to identify the factors associated with MB positivity. Survival curves were generated using the Kaplan-Meier method. RESULTS: Among 276 AAV patients (1995-2018), 101 had an MB. Seventy-eight patients were included: 33 with GPA, 25 with MPA and 20 with EGPA. MB samples were positive in 45 cases (58%): 17 GPA, 16 MPA and 12 EGPA. Univariate analysis focussed on GPA and MPA, revealed that the MB yield was higher in females [22/31 (71%) vs 11/27 (41%); P = 0.02] and in anti-MPO patients [25/37 (68%) vs 6/19 (32%) for anti-PR3; P = 0.01]. By multivariate analysis, three factors predicted MB positivity: anti-MPO ANCA [odds ratio (OR) 10.67 (CI 2.09, 81.68)], female sex [OR 5.3 (CI 1.16, 32.35)] and neutrophil count [OR 1.33 (CI 1.07, 1.8)]. MB positivity had no impact on relapse, death or end-stage renal disease-free survival. CONCLUSIONS: MB is a safe and efficient diagnostic tool for AAV. Predictors of MB yield include ANCA type, sex and neutrophil count. MB cannot substitute for kidney biopsy when indicated, but should be considered in other cases.

Risk factors for symptomatic vascular events in giant cell arteritis: a study of 254 patients with large-vessel imaging at diagnosis.

AIMS: To identify factors associated with vascular events in patients with giant cell arteritis (GCA). METHODS: We performed a retrospective study of GCA patients diagnosed over a 20-year-period, who all underwent vascular imaging evaluation at diagnosis. Symptomatic vascular events were defined as the occurrence of any aortic event (aortic dissection or symptomatic aortic aneurysm), stroke, myocardial infarction, limb or mesenteric ischemia and de novo lower limbs arteritis stage 3 or 4. Patients with symptomatic vascular event (VE+) and without were compared, and risk factors were identified in a multivariable analysis. RESULTS: Thirty-nine (15.4%) of the 254 included patients experienced at least one symptomatic vascular event during follow-up, with a median time of 21.5 months. Arterial hypertension, diabetes, lower limbs arteritis or vascular complication at diagnosis were more frequent in VE+ patients (p < 0.05), as an abnormal computed tomography (CT)-scan at diagnosis (p = 0.04), aortitis (p = 0.01), particularly of the descending thoracic aorta (p = 0.03) and atheroma (p = 0.03). Deaths were more frequent in the VE+ group (37.1 versus 10.3%, p = 0.0003). In multivariable analysis, aortic surgery [hazard ratio (HR): 10.46 (1.41-77.80), p = 0.02], stroke [HR: 22.32 (3.69-135.05), p < 0.001], upper limb ischemia [HR: 20.27 (2.05-200.12), p = 0.01], lower limb ischemia [HR: 76.57 (2.89-2027.69), p = 0.009], aortic atheroma [HR: 3.06 (1.06-8.82), p = 0.04] and aortitis of the descending thoracic aorta on CT-scan at diagnosis [HR: 4.64 (1.56-13.75), p = 0.006] were independent predictive factors of a vascular event. CONCLUSION: In this study on GCA cases with large vessels imaging at diagnosis, aortic surgery, stroke, upper or lower limb ischemia, aortic atheroma and aortitis of the descending thoracic aorta on CT-scan, at GCA diagnosis, were independent predictive factors of a vascular event. PLAIN LANGUAGE SUMMARY: Risk factors for symptomatic vascular events in giant cell arteritisThis study was performed to identify the risk factors for developing symptomatic vascular event during giant cell arteritis (GCA) because these are poorly known.We performed a retrospective study of GCA patients diagnosed over a 20-year-period, who all underwent vascular imaging evaluation at diagnosis.Patients with symptomatic vascular event (VE+) and without (VE-) were compared, and risk factors were identified in a multivariable analysis.Thirty-nine patients experienced at least one symptomatic vascular event during follow-up, with a median time of 21.5 months.Arterial hypertension, diabetes, lower limbs arteritis or vascular complication at diagnosis were significantly more frequent in VE+ patients, as an abnormal CT-scan at diagnosis, aortitis, particularly of the descending thoracic aorta and atheroma. Deaths were more frequent in the VE+ group.Among 254 GCA patients, 39 experienced at least one vascular event during follow-up.Aortic surgery, stroke, upper and lower limb ischemia were vascular event risk factors.Aortic atheroma and descending thoracic aorta aortitis on CT-scan were vascular event risk factors.This study on GCA cases with large vessels imaging at diagnosis, showed that aortic surgery, stroke, upper or lower limb ischemia, aortic atheroma and aortitis of the descending thoracic aorta on CT-scan, at GCA diagnosis, were independent predictive factors of a vascular event.

Large-vessel involvement is predictive of multiple relapses in giant cell arteritis.

BACKGROUND: Giant cell arteritis (GCA) is the most common systemic vasculitis. Relapses are frequent. The aim of this study was to identify relapse risk factors in patients with GCA with complete large-vessel imaging at diagnosis. METHODS: Patients with GCA followed in our institution between April 1998 and April 2018 were included retrospectively. We included only patients who had undergone large vascular imaging investigations at diagnosis by computed tomography (CT)-scan and/or positron emission tomography (PET)-scan and/or angio-magnetic resonance imaging (MRI). Clinical, biological, and radiological data were collected. Relapse was defined as the reappearance of GCA symptoms, with concomitant increase in inflammatory markers, requiring treatment adjustment. Relapsing patients (R) and non-relapsing patients (NR) were compared. Relapse and multiple relapses (>2) risk factors were identified in multivariable Cox analyses. RESULTS: This study included 254 patients (73.2% women), with a median age of 72 years at diagnosis and a median follow up of 32.5 months. At diagnosis, 160 patients (63%) had an inflammatory large-vessel involvement on imaging, 46.1% (117 patients) relapsed at least once, and 21.3% (54 patients) had multiple relapses. The median delay of first relapse after diagnosis was 9 months. The second relapse delay was 21.5 months. NR patients had more stroke at diagnosis than R (p = 0.03) and the brachiocephalic trunk was involved more frequently on CT-scan (p = 0.046), as carotids (p = 0.02) in R patients. Multivariate Cox model identified male gender [hazard ratio (HR): 0.51, confidence interval (CI) (0.27-0.96), p = 0.04] as a relapse protective factor, and peripheral musculoskeletal manifestations [HR: 1.74 (1.03-2.94), p = 0.004] as a relapse risk factor. Peripheral musculoskeletal manifestations [HR: 2.78 (1.23-6.28), p = 0.014], negative temporal artery biopsy [HR: 2.29 (1.18-4.45), p = 0.015], large-vessel involvement like upper limb ischemia [HR: 8.84 (2.48-31.56), p = 0.001] and inflammation of arm arteries on CT-scan [HR: 2.39 (1.02-5.58), p = 0.04] at diagnosis were risk factors of multiple relapses. CONCLUSION: Male gender was a protective factor for GCA relapse and peripheral musculoskeletal manifestations appeared as a relapsing risk factor. Moreover, this study identified a particular clinical phenotype of multi-relapsing patients with GCA, characterized by peripheral musculoskeletal manifestations, negative temporal artery biopsy, and large-vessel involvement with upper limb ischemia or inflammation of arm arteries. PLAIN LANGUAGE SUMMARY: At giant cell arteritis diagnosis, large-vessel inflammatory involvement is predictive of multiple relapses 46.1% of patients with GCA relapse, and 21.3% undergo multiple relapses;Male gender appears as a protective factor for relapsing in GCA;Peripheral musculoskeletal manifestations are a relapse and multiple relapses risk factor;A negative temporal artery biopsy is predictive of multiple relapses;Large-vessel involvement is predictive of multiple relapses.

Bronchiectasis is highly prevalent in anti-MPO ANCA-associated vasculitis and is associated with a distinct disease presentation.

OBJECTIVES: To assess the prevalence of bronchiectasis in a Western cohort with ANCA-positive granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) and its correlations with disease presentation and outcome. METHODS: Retrospective study of ANCA-associated vasculitis (AAV) patients followed at Nantes University Hospital (2005-2015). Clinical, biological, and follow-up data were collected through chart review. Two experienced radiologists blinded to the clinical data interpreted chest high-resolution CTs according to the Feischner Society criteria. RESULTS: Fifty-eight patients were included: 30 had MPA (51.7%) and 28 had GPA (48.3%). The median age at AAV diagnosis was 65.5 years. Anti-MPO-ANCA and anti-PR3-ANCA were present in 39 (67.2%) and 19 (32.8%) patients, respectively. Overall, bronchiectasis was found in 22 patients (37.9%), all of whom had anti-MPO ANCA. In multivariate analysis, bronchiectasis was independently associated with anti-MPO-ANCA, female gender and age at AAV diagnosis. Furthermore, anti-MPO ANCA patients with bronchiectasis had more frequent peripheral nerve involvement (54.5 vs. 17.6%, p = 0.019) and less frequent renal involvement than those without bronchiectasis (40.9% vs. 82.3%, p = 0.009). Disease course, survival and risk of severe pulmonary infection were similar in patients with and without bronchiectasis on chest CT. CONCLUSIONS: This study shows that bronchiectasis is a highly prevalent pre-existing respiratory condition in Caucasian patients with anti-MPO AAV. This subset of patients exhibits a distinct presentation. Further studies are needed to confirm these findings and clarify the clinical implications of this association. Whether the respiratory tract could be the site of initiation of anti-MPO auto-immunity remains to be investigated.

Sjögren's syndrome-associated myositis with germinal centre-like structures.

OBJECTIVE: Muscular impairment is a rare systemic manifestation of SS that is rarely described in the literature and classically non-specific, both clinically and histologically. We reviewed the cases of 4 patients with primary SS presenting with myositis and a common histologic pattern on muscular biopsy with germinal centre-like structures resembling that which occurs in salivary glands. METHODS: We analysed the data files of patients with SS who had muscular manifestations and underwent a muscular biopsy. Among 23 patients with SS who had muscle biopsies, 13 had non-specific myositis and 10 (4 primary and 6 secondary SS) had a common histologic pattern consisting of germinal centre-like structures. We analysed the data files of the 4 patients with primary SS presenting with myositis with muscular germinal-centre like structures. RESULTS: The 4 patients had an unspecific clinical presentation, with myalgias, muscular weakness and normal or elevated values of CPK. In the four patients, SS-associated myositis had common histologic characteristics, with endomysial and perimysial inflammatory infiltrate. The cellular infiltrate was composed predominantly of CD4+ T lymphocytes and B lymphocytes. The B and T CD4+ cells infiltrates may gather into masses, even forming lymphoid follicles. Three patients were treated with corticosteroids and/or hydroxychloroquine with improvement of myositis and 1 patient was lost to follow-up. CONCLUSIONS: We describe four patients with a common histologic appearance of myositis with lymphoid follicles associated with primary SS. The clinical presentation was non-specific and non-severe, with favorable outcome with corticosteroids and/or hydroxycholoroquine. The discovery of this particular histologic appearance in a muscle biopsy independent of the final diagnosis should indicate the possibility of SS.

Comparison of idiopathic (isolated) aortitis and giant cell arteritis-related aortitis. A French retrospective multicenter study of 117 patients.

OBJECTIVES: The aim of the study was to compare clinical/imaging findings and outcome in patients with idiopathic (isolated aortitis, IA) and with giant cell arteritis (GCA)-related aortitis. METHODS: Patients from 11 French internal medicine departments were retrospectively included. Aortitis was defined by aortic wall thickening >2mm and/or an aortic aneurysm on CT-scan, associated to inflammatory syndrome. Patients with GCA had at least 3 ACR criteria. Aortic events (aneurysm, dissection, aortic surgeries) were reported, and free of aortic events-survival were compared. RESULTS: Among 191 patients with non-infectious aortitis, 73 with GCA and 44 with IA were included. Patients with IA were younger (65 vs 70 years, p=0.003) and comprised more past/current smokers (43 vs 15%, p=0.0007). Aortic aneurisms were more frequent (38% vs 20%, p=0.03), and aortic wall thickening was more pronounced in IA. During follow-up (median=34 months), subsequent development of aortic aneurysm was significantly lower in GCA when compared to IA (p=0.009). GCA patients required significantly less aortic surgery during follow-up than IA patients (p=0.02). Mean age, sex ratio, inflammatory parameters, and free of aortic aneurism survival were equivalent in patients with IA ≥ 60 years when compared to patients with GCA-related aortitis. CONCLUSIONS: IA is more severe than aortitis related to GCA, with higher proportions of aortic aneurism at diagnosis and during follow-up. IA is a heterogeneous disease and its prognosis is worse in younger patients <60 years. Most patients with IA ≥ 60 years share many features with GCA-related aortitis.

Giant cell arteritis with or without aortitis at diagnosis. A retrospective study of 22 patients with longterm followup.

OBJECTIVE: Studies have shown that aortitis may be present in half the patients with recent-onset giant cell arteritis (GCA). We assessed whether aortitis at diagnosis affects longterm outcome in patients with GCA. METHODS: We retrospectively analyzed the longterm outcome of a prospective cohort of 22 patients with biopsy-proven GCA who all had aortic computed tomography (CT) evaluation at the time of diagnosis of GCA between May 1998 and November 1999. Longterm outcome, especially vascular events such as aortic aneurysm, mortality, relapses of GCA, and requirement for steroids, was assessed in 2011 by chart review and patient/physician interviews. RESULTS: At disease onset, 10/22 patients had aortitis on CT scan. Patients with and without aortitis had similar baseline characteristics, including cardiovascular risk profile. At the time of the study, 12/22 (57%) patients had died. Vascular causes of death were more frequent in patients with aortitis (5/7 vs 0/5; p = 0.02). A higher number of vascular events was noted in patients with aortitis (mean events per patient 1.33 vs 0.25; p = 0.009). Stroke was more frequent in patients with aortitis. These patients seemed to exhibit a more chronic or relapsing disease course, and they were less likely to completely discontinue steroid therapy (p = 0.009, log-rank test). CONCLUSION: Our study suggests for the first time that inflammatory aortic involvement present at onset of GCA could predict a more chronic/relapsing course of GCA, with higher steroid requirements and an increased risk for vascular events in the long term.