miR-146a and miR-146b regulate the expression of ICAM-1 in giant cell arteritis.

Giant cell arteritis (GCA) is an inflammatory disease of large/medium-sized arteries. MiRNAs are small, non-coding RNAs that inhibit gene expression at post-transcriptional level. Several miRNAs have been shown to be dysregulated in temporal artery biopsies (TABs) from GCA patients, but their role is unknown. The aims of the present work were: to gain insight into the link between inflammation and miRNA up-regulation in GCA; to identify the role of miR-146a and miR-146b. Primary cultures from TABs were treated with IL-1ß, IL-6, soluble IL-6R (sIL6R), IL-17, IL-22, IFNγ, LPS and PolyIC. Correlations between cytokine mRNA and miRNA levels were determined in inflamed TABs. Primary cultures from TABs, human aortic endothelial and smooth muscle cells and ex-vivo TAB sections were transfected with synthetic miR-146a and miR-146b to mimic miRNA activities. Cell viability, target gene expression, cytokine levels in culture supernatants were assayed. Treatment of primary cultures from TABs with IL-1ß and IL-17 increased miR-146a expression while IL-1ß, IL-6+sIL6R and IFNγ increased miR-146b expression. IFNγ and IL-1ß mRNA levels correlated with miR-146a/b levels. Following transfection, cell viability decreased only in primary cultures from TABs. Moreover, transfection of miR-146a/b mimics increased ICAM-1 gene expression and production of the soluble form of ICAM-1 by primary cultures from TABs and by ex-vivo TABs. ICAM-1 expression was higher in inflamed than normal TABs and ICAM-1 levels correlated with miR-146a/b levels. Expression of miR-146a and miR-146b in GCA appeared to be driven by inflammatory cytokines (e.g. IL-1ß, IFNγ). miR-146a and miR-146b seem responsible for the increase of soluble ICAM-1.

Eosinophilic giant cell arteritis: A different subset of disease?

OBJECTIVES: To describe the clinical findings, response to therapy and course of patients with transmural eosinophilic infiltration at temporal artery biopsy (TAB). METHODS: The study consisted of a retrospective cohort of 254 consecutive GCA patients with evidence of transmural inflammation at TAB seen at the Santa Maria Nuova Hospital over a 28-year period. The findings of the 22 patients with eosinophilic infiltration (≥ 20 eosinophils/hpf) at TAB were compared with those of 232 patients without. Among these 232 patients, we sampled 42 GCA patients matched for age, sex and follow-up duration to the 22 with eosinophilic infiltration, to compare allergic manifestations. RESULTS: GCA patients with eosinophilic infiltration compared to those without presented more frequently cranial symptoms (p = 0.052), headaches (p = 0.005), abnormalities of TAs at physical examination (p = 0.045), jaw claudication (p = 0.024), and systemic manifestations (p = 0.016) and had higher CRP levels at diagnosis (p = 0.001). Regarding histological lesions, a severe transmural inflammation, laminar necrosis and intraluminal acute thrombosis were more frequently observed in patients with eosinophilic infiltration (p = 0.066, p < 0.001, and p = 0.010, respectively). Long-term remission and flares were similar in the two groups. When 21 GCA patients with eosinophilic infiltration were compared to 42 without, blood eosinophilic counts at diagnosis were normal and no patients had evidence or developed allergic manifestations and/or clinical findings of systemic necrotizing vasculitis. CONCLUSION: Patients with transmural eosinophilic infiltration represent a subset of GCA with cranial disease and more severe inflammation.

Effectiveness and safety of a 26-week taper regimen of glucocorticoid in GCA patients: Results from a prospective cohort study.

OBJECTIVES: To assess the effectiveness and safety of the 26-week tapering regimen of glucocorticoids (GC) used in the GiACTA trial in a prospective cohort of treatment-naive, biopsy-proven GCA patients. METHODS: Patients with a new diagnosis of biopsy-proven GCA enrolled in the GC arm of the START project (molecular stratification of patients with GCA to tailor GC and tocilizumab therapy) were included. All patients were treated with the 26-week taper regimen of GC used in the GiACTA trial. The primary endpoint was the rate of relapse-free remission at week 52. The secondary endpoints were the proportion of patients with incident aortic damage, cumulative GC doses and GC-related adverse events (AE). RESULTS: 22 patients were included between December 2018 and February 2022. At week 52, 10 patients (45 %, 95 % CI 24-68) were in relapse-free remission. After a median (IQR) follow-up of 35 (22-40) months, 7 patients (32 %, 95 % CI 14-55) were in relapse-free remission. 18 patients with baseline large-vessel imaging underwent CT angiography at the end of the follow-up. No patients had evidence of new aortic dilation, significant progression of aortic damage or large vessel stenosis. 15/22 patients (68 %) had at least one relapse during follow-up. No patients developed visual or cerebrovascular manifestations during relapses. 15/22 (68 %) patients had at least one GC-related AE. CONCLUSIONS: A 26 week taper regimen of GC was effective and safe in inducing and maintaining remission in a sizeable proportion of newly diagnosed GCA patients. However, the frequency of GC-related adverse events was high.

C-reactive protein gene polymorphisms influence susceptibility and outcomes of biopsy-proven giant cell arteritis in Italian patients.

OBJECTIVES: To investigate potential associations between the two functional C-reactive protein (CRP) gene polymorphisms at position 3872C>T (rs1205) and 4741G>C (rs3093068) and susceptibility, clinical expression, laboratory and pathological findings, and outcomes of giant cell arteritis (GCA) in a Nothern Italian population. METHODS: One hundred and seventy Italian patients with biopsy-proven GCA resident in Reggio Emilia area, Italy, and 200 healthy controls from the same geographic area were genotyped for rs1205 and rs3093068 CRP gene polymorphisms by molecular methods. The patients were subgrouped on the basis of the presence or absence of clinical manifestations, histological and laboratory findings, and outcomes. RESULTS: The distribution of rs1205 genotype was significantly different between GCA patients and controls (p=0.018). Homozygosity for T allele was significantly more frequent in GCA patients compared to controls [p=0.006; odds ratio (OR): 2.28 (95% CI: 1.1, 4.8)]. The distribution of rs3093068 genotype differed significantly between GCA patients and controls (p=0.010). Allele C and the carriers of the C allele (C/C+C/G) of rs3093068 genotype were significantly less frequent in GCA patients compared to controls [p=0.002, OR: 0.39 (95% CI: 0.24-0.73); p=0.002, OR: 0.35 (95% CI: 0.17-0.70), respectively]. No significant associations were found between the two polymorphisms and baseline clinical manifestations. The carriers of the allele C of rs3093068 genotype had significantly higher CRP values at diagnosis (13.2±5.0 vs. 8.3±6.0 mg/dl, p=0.007). Homozygosity for T allele of rs1205 genotype had a significantly more frequent eosinophil infiltration of the temporal artery wall (21.4% vs. 6.0%) (p=0.010, OR 4.28;1.31-13.98) than patients carrying the allele C. Carriers of the allele T of rs1205 genotype had lower glucocorticoid (GC) treatment duration (p=0.041), lower cumulative total GC dose (p=0.017), and higher prevalence of long-term remission (p=0.024). CONCLUSIONS: CRP gene rs1205 and rs3093068 polymorphisms influence GCA susceptibility and its outcomes.

Pros and cons of TNF inhibitors and tocilizumab in the treatment of large-vessel vasculitis.

Large-vessel vasculitides (LVVs) include giant cell arteritis (GCA) and Takayasu's arteritis (TAK). Even if similar, these two entities differ in terms of treatment and outcomes.High doses of glucocorticoids (GCs) are still the first choice for the treatment of both conditions. However, adjunctive therapies are recommended in selected patients in order to decrease the risk of relapse and the amount of side effects related to GCs. Tumour necrosis factor α inhibitors (TNFis) and tocilizumab (TCZ) are used for the treatment of LVVs, with some differences. In GCA, TCZ has been proved to be effective and safe in inducing remission with some open questions still remaining, whereas data about TNFis are scarce and non-conclusive. On the contrary, in TAK either TNFis or TCZ seem to be able to control symptoms and angiographic progression in refractory forms.However, their place in the management of treatment must still be clarified, and as a result the American College of Rheumatology and EULAR guidelines slightly differ in the recommendations about when and what treatment to start. Thus, the aim of this review is to look at the evidence on the use of TNFis and TCZ in LVVs, outlining the pros and cons of both therapies.

What to Know About Biopsy Sampling and Pathology in Vasculitis?

PURPOSE OF REVIEW: To summarize the histologic findings of vasculitis, and to give some practical considerations on biopsy samples. RECENT FINDINGS: The larger use of imaging and the discoveries of serological markers in the diagnosis of vasculitis have increased the clinical recognition of these entities. Nevertheless, biopsy remains the gold standard for diagnosis in most cases. So far, biopsies are also useful to obtain information about prognosis and to guide a more specific treatment. In recent years, less invasive diagnostic approaches have become available, lowering the risks related to the procedure and permitting a definite diagnosis in most cases. Histological examination permits a definite diagnosis of vasculitis. However, the findings may be nonspecific if not evaluated in the proper clinical setting. The interaction between clinicians and pathologists is crucial to obtain a definite diagnosis.

VEXAS Syndrome: A Case Series From a Single-Center Cohort of Italian Patients With Vasculitis.

OBJECTIVE: To identify patients with VEXAS syndrome (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic syndrome) from a single-center cohort of Italian patients with vasculitis, using a clinically oriented phenotype-first approach. METHODS: We retrospectively reviewed the clinical records of 147 consecutive male patients followed up in our vasculitis clinic from 2013 to date. All patients with a diagnosis of vasculitis and treatment-resistant manifestations of inflammation, persistently elevated inflammation markers, and hematologic abnormalities were identified. Bone marrow aspirates were examined for the presence of vacuoles. Sequencing of ubiquitin-activating enzyme E1 (UBA-1) was performed using genomic DNA from peripheral blood leukocytes or bone marrow tissue. RESULTS: Seven patients with vasculitis and concomitant features of VEXAS syndrome were identified. A final diagnosis of VEXAS syndrome was made in 3 of the 5 patients who underwent sequencing of UBA-1 (diagnosis was made postmortem for 1 patient). In all 3 patients, examination of the bone marrow aspirate revealed vacuoles characteristic of VEXAS syndrome, and all 3 patients met the definitive World Health Organization criteria for myelodysplastic syndrome. Cytogenetic analysis showed normal karyotypes in all 3 patients. CONCLUSION: To our knowledge, this is the first report of VEXAS syndrome associated with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis. Our data emphasize the need to consider VEXAS syndrome when evaluating patients with various forms of systemic vasculitis. The novel association between VEXAS syndrome and ANCA-associated vasculitis reported herein warrants further investigation.

Efficacy and safety of TNF-α antagonists and tocilizumab in Takayasu arteritis: multicentre retrospective study of 209 patients.

OBJECTIVE: To assess the safety and the efficacy of TNF-α antagonists and tocilizumab in patients with Takayasu arteritis (TAK). METHODS: A total of 209 patients with TAK [median age 29 years (interquartile range 7-62)], 186 (89%) females] were included. They received either TNF-α antagonists [n = 132 (63%) with 172 lines; infliximab (n = 109), adalimumab (n = 45), golimumab (n = 8), certolizumab (n = 6) and etanercept (n = 5)] or tocilizumab [n = 77 (37%) with 121 lines; i.v. and s.c. in 95 and 26 cases, respectively]. RESULTS: A complete response at 6 months was evidenced in 101/152 (66%) patients on TNF-α antagonists and 75/107 (70%) patients on tocilizumab. Age ≥30 years [odds ratio 2.09 (95% CI 1.09, 3.99)] was associated with complete response, whereas vascular signs [OR 0.26 (95% CI 0.1, 0.65)], baseline prednisone ≥20 mg/day [OR 0.51 (95% CI 0.28, 0.93)] were negatively associated with the complete response to TNF-α antagonists or tocilizumab. During a median follow-up of 36 months, 103 relapses were noted. Supra-aortic branches and thoracic aorta involvement [HR 2.44 (95% CI 1.06, 5.65) and 3.66 (1.18, 11.4), respectively] and systemic signs at baseline [HR 2.01 (95% CI 1.30, 3.11)] were significantly associated with relapse. The cumulative incidence of treatment discontinuation and relapse were similar in TNF-α antagonists and tocilizumab. Fifty-eight (20%) adverse effects occurred on biologic targeted therapies [37 (21%) on TNF-α antagonists and 21 (17%) on tocilizumab (P = 0.4), respectively]. CONCLUSION: This large multicentre study shows high efficacy of biologic targeted treatments in refractory TAK. Efficacy, relapse and drug retention rate were equivalent with TNF-α antagonists and tocilizumab.

Incidence and prevalence of large vessel vasculitis (giant cell arteritis and Takayasu arteritis) in northern Italy: A population-based study.

OBJECTIVES: To investigate the epidemiology of the entire spectrum of large vessel vasculitis (LVV) in a well-defined population from a Northern Italian area. METHODS: All patients with incident giant cell arteritis (GCA) diagnosed from 2005 to 2016 and all patients with incident Takayasu arteritis (TAK) diagnosed from 1998 to 2016 living in the Reggio Emilia area were identified. Only patients satisfying the modified inclusion criteria of the GiACTA trial, and the 1990 ACR classification criteria for TAK were included. The epidemiology of cranial- and LV-GCA was separately evaluated. RESULTS: 207 patients were diagnosed with GCA and 5 with TAK. 123 patients had cranial-GCA, 53 patients had LV-GCA, and the remaining 31 patients had overlapping features. The standardized annual incidence rate of GCA was 8.3 (95% CI 7.1, 9.4) per 100,000 population ages ≥50 years. The standardized annual incidence rate of cranial-GCA (6.1 [95% CI 5.1, 7.1] per 100,000 population ages ≥50 years) was double the rate of LV-GCA (3.4 [95% CI 2.7, 4.2]). The age-specific incidence rates were similar in the <70 and >90 years age groups, but they were higher in cranial-GCA than in LV-GCA in the age groups 70-79 and 80-89 years. The age- and sex-adjusted annual incidence rate of TAK was 0.5 (95% CI 0.1, 1.2) per 1,000,000 population. CONCLUSION: Incidence of GCA is higher than previously reported by study evaluating only biopsy-proven or ACR classification criteria confirmed cases. Cranial-GCA and LV-GCA have epidemiological differences. TAK is an extremely rare disease also in Italy.

Association Between Specimen Length and Number of Sections and Diagnostic Yield of Temporal Artery Biopsy for Giant Cell Arteritis.

OBJECTIVE: To investigate the association between specimen length and number of sections evaluated and the diagnostic yield of temporal artery biopsy (TAB) for giant cell arteritis (GCA). METHODS: A pathologist reviewed all TABs performed for suspected GCA between January 1991 and December 2012. The blocks of all the inadequate and negative biopsy specimens were recut, and further slides at deeper levels were stained with hematoxylin and eosin in order to avoid missing inflammatory changes. RESULTS: In total, findings from 662 TABs were included in the study (71% female; mean age 73.2 years). A total of 427 TAB specimens (65%) were classified as negative, and 235 (35%) were classified as positive for GCA. Compared to those with negative TAB results, patients with positive TAB results were older and more frequently female. There was no difference in postfixation TAB specimen length between TAB specimens negative and positive for GCA (mean 6.5 mm versus 6.9 mm; P = 0.068). Cuts of additional biopsy sections revealed inflammation at deeper levels in 26 of 408 TAB specimens (6.4%) originally reported as uninflamed. The inflamed section was the second in 14 TAB specimens, the third in 9 specimens, and the fourth in 3 specimens. Piecewise logistic regression identified 5 mm as the TAB specimen length change point for diagnostic sensitivity. Compared to a TAB specimen length of <5 mm, the age- and sex-adjusted odds ratio for positive TAB results in samples ≥5 mm long was 1.5 (95% confidence interval 1.0-2.0), P = 0.032. CONCLUSION: A postfixation TAB specimen length of at least 5 mm should be sufficient to make a histologic diagnosis of GCA. In order not to miss inflammatory changes, at least 3 further sections at deeper levels should be evaluated in all negative TAB specimens.

Significance of inflammation restricted to adventitial/periadventitial tissue on temporal artery biopsy.

OBJECTIVE: To evaluate the characteristics and significance of inflammation restricted (RI) to the adventitial and/or periadventitial tissue on temporal artery biopsy (TAB). METHODS: We studied a retrospective cohort of 80 patients with RI, extending our earlier series of 39 patients. For comparison purposes, we collected the same data from 254 patients with transmural inflammation (TMI) and 81 TAB-negative patients. A review of the literature was also performed. RESULTS: A final diagnosis of giant cells arteritis (GCA) and/or polymyalgia rheumatica (PMR) was observed in 86% of patients with RI. Compared to TMI, GCA diagnosis was significantly less frequently observed in patients with RI and in those TAB-negative (p < 0.0001), while cranial manifestations were significantly less frequent (p = 0.001) and ESR and CRP values at diagnosis significantly reduced (p < 0.0001). PMR, permanent visual loss, and large vessel involvement at diagnosis were equally present in the 3 subgroups. The median duration of prednisone therapy, the cumulative prednisone dosages, and the relapse and long-term remission rates were similar between patients with GCA-RI and those with TMI. The positive likelihood ratios (LRs) of pathological evidence of RI at TAB for GCA or GCA/PMR diagnoses were 0.88 (CI, 0.61-1.27) and 1.15 (CI, 0.67-1.99), while that of inflammation limited to adventitia was 1.37 (CI, 0.59-3.19) and 3.77 (CI, 0.53-26.72). In the literature review, the positive LR of RI for GCA diagnosis was 0.92 (CI, 0.68-1.25). CONCLUSION: A large part of the patients with RI have GCA/PMR, however, the diagnostic value of RI for GCA diagnosis is not relevant.

Relapses and long-term remission in large vessel giant cell arteritis in northern Italy: Characteristics and predictors in a long-term follow-up study.

OBJECTIVE: To evaluate characteristics and predictors of relapses and long-term remission in an Italian cohort of patients with large-vessel (LV) giant cell arteritis (GCA). METHODS: We evaluated 87 consecutive patients with LV-GCA followed up at the Rheumatology Unit of Reggio Emilia Hospital (Italy) for at least 2 years. Patients with relapses and long-term remission were compared to those without. A group of 34 patients with biopsy proven GCA without LV vasculitis (LVV) at diagnosis was considered for comparison. PATIENTS: 37 patients (42.5%) experienced one or more relapses. Nineteen (37.2%) of the 51 relapses were experienced during the first year after diagnosis. The majority of relapses occurred with doses of prednisone (PDN) ≤ 10 mg/day (74.5%). Polymyalgia rheumatica (PMR) (41.2%) and worsening at imaging of LVV (39.2%) were the most frequently observed relapsing manifestations. The total cumulative prednisone dose was significantly higher (p < 0.0001) and the total duration of PDN treatment longer (p < 0.0001) in relapsing patients compared to those without relapses. Relapsing patients had at diagnosis more frequently fever ≥ 38°C (p = 0.03) and visual manifestations (p = 0.03), and less frequently long-term remission (p = 0.002). In the multivariate model fever ≥ 38°C (HR 2.30, 95%CI:1.11-4.78) and total cumulative PDN dose (HR 1.18, 95%CI: 1.08-1.30) were significantly associated with an increased risk of relapses, while aortic arch involvement at imaging at diagnosis (HR 0.26, 95%CI: 0.11-0.59) and long-term remission (HR 0.27, 95%CI: 0.11-0.65) with a reduced risk. 35/84 patients (41.6%) experienced long-term remission. PMR and disease relapses were less frequently observed (p = 0.04 and p = 0.002, respectively), and the total cumulative prednisone dose was lower (p < 0.001) in patients with long-term remission compared to those without. In the multivariate model the presence of relapses (HR 0.21, 95%CI: 0.07-0.62) and the total cumulative PDN dose (HR 0.85, 95%CI: 0.77-0.95) were significantly negatively associated with long-term remission. CONCLUSION: In our cohort of patients with LV GCA we identified predictors of a relapsing course and long-term remission, which were observed in around half of the patients.

Comparison of biopsy-proven giant cell arteritis in North America and Southern Europe: a population-based study.

OBJECTIVES: To compare clinical characteristics, treatment and prognosis of two population-based cohorts of patients with biopsy-proven giant cell arteritis (GCA) from Olmsted County, Minnesota, USA (Olmsted cohort) and the Reggio Emilia area, Northern Italy (Reggio cohort). METHODS: All patients residing in Olmsted County and the Reggio Emilia area with a new diagnosis of biopsy-proven GCA in 1986-2007 were retrospectively identified. Patients were followed from GCA diagnosis to death, migration or September 2011. RESULTS: The study included 110 patients in the Olmsted and 144 in the Reggio cohort. Compared with the Olmsted cohort, patients from the Reggio cohort had longer duration of symptoms prior to diagnosis (median 1.4 months vs. 0.7, p<0.001) and were younger (mean 74.6 years vs. 77.8, p=0.002), more likely to have cranial symptoms (93% vs. 86%, p=0.048), permanent vision loss (21% vs. 6%, p=0.001) and systemic symptoms (67% vs. 46%, p=0.001). ESR and CRP were higher (mean 88 mm/h vs. 73, and 89.0 mg/L vs. 35.2, both p<0.001) in the Reggio cohort. Patients from the Olmsted cohort received a higher initial prednisone dose (mean 53.6 mg/day vs. 49.5, p=0.001). There were no differences in relapse rates, cumulative glucocorticoid (GC) dosages at 1, 2 and 5 years, and time to first GC discontinuation. CONCLUSIONS: Geographical, genetic and/or environmental factors may contribute to the different clinical features at onset of GCA observed in this study.

Imbalance between angiogenic and anti-angiogenic factors in sera from patients with large-vessel vasculitis.

OBJECTIVES: To investigate serum levels of a panel of angiogenic inducers (VEGF, FGF-2, Angiopoietin 1, -2, soluble VCAM-1) and inhibitors (angiostatin, endostatin, pentraxin-3) in patients with giant cell arteritis (GCA) and Takayasu's arteritis (TAK), in order to gain further insights into the molecular mechanisms driving angiogenesis dysregulation in large-vessel vasculitis (LVV). METHODS: Sera were obtained from 33 TAK patients and 14 GCA patients and from two groups of age-matched normal controls (NC). Disease activity was assessed using 18F-FDG PET/CT and clinical indices including NIH/Kerr criteria and ITAS. Angiogenic and anti-angiogenic factor serum levels were evaluated using commercial ELISA kits. Pentraxin 3 (PTX3) serum levels were evaluated by non-commercial ELISA, as already described. RESULTS: Among the angiogenic factors, only VEGF serum levels were significantly higher in TAK patients compared to NC. No difference was found between angiogenic factor levels in GCA patients compared to those detected in NC. Anti-angiogenic factor (Angiostatin, Endostatin, PTX3) serum levels were significantly higher in both GCA and TAK patients compared to NC. Significant associations were observed between VEGF and PTX3 levels and disease activity evaluated using PET scan and clinical indices. Cluster analysis based on PET scan scores in TAK patients showed significant ordered differences in VEGF and angiostatin serum levels. Indeed, we noted a progressive increase of VEGF and angiostatin from NC to the cluster including patients with the highest and more diffuse scan positivity. CONCLUSIONS: Our overall results demonstrate a circulating molecular profile characterised by a prevailing expression of anti-angiogenic soluble factors.

Interleukin-6 expression in inflamed and non-inflamed temporal arteries from patients with giant cell arteritis.

OBJECTIVES: To evaluate whether interleukin-6 expression in the temporal arteries could be a more sensitive marker of active inflammation compared to the presence of an inflammatory infiltrate. METHODS: Sixty-three formalin-fixed, paraffin-embedded temporal artery biopsies performed between 2009 and 2012 from 32 patients with biopsy-proven giant cell arteritis, 8 patients with a negative biopsy but with a final diagnosis of giant cell arteritis, and 23 controls (patients with an initial clinical suspicion of giant cell arteritis in whom an alternative diagnosis subsequently was made) were examined. Biopsy specimens showing a transmural inflammatory infiltrate were considered positive for giant cell arteritis. Immunochemistry was performed to detect interleukin-6 in the temporal artery specimens. Slides of temporal artery biopsies were independently assessed by five readers. Interleukin-6 expression was graded as 0 (absent), 1 (mild), 2 (moderate) and 3 (marked). We considered anti-IL-6 staining positive if staining was of grade 2 or 3. RESULTS: Temporal artery biopsies specimens from patients with biopsy-proven giant cell arteritis, biopsy-negative giant cell arteritis and controls were positive for anti-interleukin-6 staining in 59%, 13% and 48% of cases, respectively. CONCLUSIONS: Interleukin-6 expression does not increase the sensitivity of temporal artery biopsy in patients with giant cell arteritis who have morphologically uninflamed arteries.

Aortic dilatation in patients with large vessel vasculitis: A longitudinal case control study using PET/CT.

OBJECTIVE: To evaluate aortic diameter and predictors of aortic dilatation using 18FDG-PET/CT in a longitudinally followed cohort of patients with large vessel vasculitis (LVV) compared with controls. METHODS: All consecutive patients with LVV who underwent at least 2 PET/CT scans between January 2008 and May 2015 were included. The first and last PET/CT study was evaluated by a radiologist and a nuclear medicine physician. Diameter and FDG uptake of the aorta was measured at 4 different levels: ascending, descending thoracic, suprarenal and infrarenal abdominal aorta. Twenty-nine age- and sex-matched patients with lymphoma who underwent at least 2 PET/CT scans in the same time interval were selected as controls. RESULTS: 93 patients with LVV were included in the study. In the time interval between first and last PET/CT study (median time 31 months), the diameter of the ascending, descending thoracic and suprarenal abdominal aorta significantly increased in LVV patients but not in controls. At last PET/CT, patients with LVV compared with controls had higher diameter of ascending [35.41 (5.54) vs 32.97 (4.11) mm, p = 0.029], descending thoracic [28.42 (4.82) vs 25.72 (3.55) mm, p = 0.007] and suprarenal abdominal aorta, mean [25.34 (7.01) vs 22.16 (3.26) mm, p = 0.005] and more frequently had aortic dilatation [19% vs 3%, p = 0.023]. Significant predictors of aortic dilatation were male sex [OR 7.27, p = 0.001] and, only for GCA, hypertension [OR 6.30, p = 0.031]. Finally, GCA patients with aortic FDG uptake grade 3 at first PET/CT, compared to those with aortic FDG uptake ≤2, had significantly higher aortic diameter. CONCLUSIONS: Patients with LVV are at increased risk of aortic dilatation compared with age- and sex-matched controls. Significant predictors of aortic dilatation are male sex and, only for GCA, hypertension. GCA patients with aortic FDG uptake grade 3 are at increased risk of aortic dilatation.

Survival predictors in biopsy-proven giant cell arteritis: a northern Italian population-based study.

OBJECTIVE: To evaluate the influence of disease-related findings and treatment outcomes on survival in a population-based cohort of Northern Italian patients with GCA. METHODS: A total of 281 patients with incident temporal artery biopsy (TAB)-proven GCA, diagnosed over a 26-year period (1986-2012) and living in the Reggio Emilia area, were retrospectively evaluated. We analysed clinical, imaging and laboratory findings at diagnosis, pathological patterns of TAB, CS treatment and therapeutic outcomes, and traditional cardiovascular risk factors as factors predictive of survival. RESULTS: Univariate analysis showed that increased mortality was associated with large vessel involvement at diagnosis [hazard ratio (HR) 5.84], while reduced mortality was associated with female sex (HR 0.66), PMR (HR 0.54), higher haemoglobin levels (HR 0.84) at diagnosis, long-term remission (HR 0.47) and inflammation limited to adventitia or to the adventitial vasa vasorum (HR 0.48) at TAB examination. Multivariate analysis confirmed the association between increased mortality and large vessel involvement (HR 5.14) at diagnosis, between reduced mortality and PMR (HR 0.57) at diagnosis and adventitial inflammation (HR 0.31) at TAB. CONCLUSION: PMR at diagnosis and inflammation limited to the adventitia at TAB appear to identify subsets of patients with more benign disease, while large vessel involvement at diagnosis is associated with reduced survival.

A TNFSF13B functional variant is not involved in systemic sclerosis and giant cell arteritis susceptibility.

BACKGROUND: The TNFSF13B (TNF superfamily member 13b) gene encodes BAFF, a cytokine with a crucial role in the differentiation and activation of B cells. An insertion-deletion variant (GCTGT→A) of this gene, leading to increased levels of BAFF, has been recently implicated in the genetic predisposition to several autoimmune diseases, including multiple sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. Based on the elevated levels of this cytokine found in patients with giant cell arteritis (GCA) and systemic sclerosis (SSc), we aimed to assess whether this functional variant also represents a novel genetic risk factor for these two disorders. METHODS: A total of 1,728 biopsy-proven GCA patients from 4 European cohorts, 4,584 SSc patients from 3 European cohorts and 5,160 ethnically-matched healthy controls were included in the study. The single nucleotide polymorphism (SNP) rs374039502, which colocalizes with the genetic variant previously implicated in autoimmunity, was genotyped using a custom TaqMan assay. First, association analysis was conducted in each independent cohort using χ2 test in Plink (v1.9). Subsequently, different case/control sets were meta-analyzed by the inverse variance method. RESULTS: No statistically significant differences were found when allele distributions were compared between cases and controls for any of the analyzed cohorts. Similarly, combined analysis of the different sets evidenced a lack of association of the rs374039502 variant with GCA (P = 0.421; OR (95% CI) = 0.92 (0.75-1.13)) and SSc (P = 0.500; OR (95% CI) = 1.05 (0.91-1.22)). The stratified analysis considering the main clinical subphenotypes of these diseases yielded similar negative results. CONCLUSION: Our data suggest that the TNFSF13B functional variant does not contribute to the genetic network underlying GCA and SSc.

Increased expression of interleukin-22 in patients with giant cell arteritis.

Objectives: GCA is characterized by arterial remodelling driven by inflammation. IL-22 is an attractive cytokine which acts at the crosstalk between immune and stromal cells. We hypothesized that IL-22 might be induced in GCA and might be involved in disease pathogenesis. Methods: Patients subjected to temporal artery biopsies (TABs) naïve from therapy were enrolled: 27 biopsy-proven GCA, 8 biopsy-negative GCA, 21 biopsy-negative non-GCA patients. Expression of IL-22 was determined in TABs by immunohystochemistry, in plasma by ELISA, in peripheral blood mononuclear cells by real-time PCR and flow cytometry. Effects of IL-22 on viability and gene expression of primary cultures obtained from TABs were also evaluated. Results: Inflamed TABs from GCA patients showed a higher expression of IL-22 and IL-22 specific receptor subunit (IL-22R1) than non-inflamed TABs. IL-22 was expressed in infiltrating immune cells and spindle shaped cells, IL-22R1 was expressed in endothelial cells. Patients with biopsy-proven GCA showed increased levels of IL-22 in plasma than patients with biopsy-negative GCA, without GCA and healthy subjects. Peripheral blood mononuclear cells from GCA patients expressed higher IL-22 transcript than healthy subjects. After stimulation in vitro with phorbol 12-myristate 13-acetate and ionomycin, the frequencies of Th22 and IL-22+ CD4+ lymphocytes were similar between patients with and without GCA. Treatment with IL-22 of primary cultures obtained from TABs increased cell viability under stress conditions and expression of B-cell activating factor. Conclusion: IL-22 is increased in patients with GCA and affects viability and gene expression of arterial cells, supporting a potential role in disease pathogenesis.