Objectives The present study validates the 2022 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) classification criteria for Takayasu’s arteritis (TAK) compared with 1990 ACR TAK classification criteria. Methods The fulfillment of 2022 ACR/EULAR and 1990 ACR TAK criteria from four referral centers was assessed for TAK compared with extracranial giant cell arteritis (EC-GCA) and other controls. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratio of a positive test (LR+) or negative test (LR-), and area under receiver operating characteristics curve (AUC) were calculated. Results Among 504 TAK (404 females) and 222 controls (151 females, 144 EC-GCA), the 2022 ACR/EULAR criteria had better sensitivity (95.83% vs 82.94%) and NPV but poorer specificity (63.51% vs 90.54%), PPV, LR+, LR-, and AUC at the pre-determined cut-offs than 1990 ACR criteria. The 2022 ACR/EULAR criteria had greater specificity (76.06% vs 57.62%) and AUC (0.845 vs 0.771) with similar sensitivity (93% vs 96.53%) in males than in females. The 2022 ACR/EULAR criteria performed similarly with only EC-GCA as controls (sensitivity 95.83%, specificity 60.42%, AUC 0.781). Sensitivity remained similar, whereas specificity was higher for 40-60 vs < 40 years. Cut-offs ≥6 (sensitivity 91.87%, specificity 82.88%) and ≥7 (sensitivity 86.71%, specificity 86.49%), or removing the point for female sex (sensitivity 92.64%, specificity 81.08%) greatly improved balance between sensitivity and specificity. Conclusion The poor specificity of the 2022 ACR/EULAR TAK criteria in real-life settings was improved by increasing the cut-off to 6 or 7 or removing the point for female sex.

No abstract

BackgroundThe 2022 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) classification criteria for Takayasu arteritis (TAK) were recently published [1].ObjectivesTo validate and evaluate the 2022 ACR/EULAR TAK classification criteria in the light of the 1990 ACR TAK classification criteria [2].MethodsClinical data of TAK patients from four referral centers (two from Italy and two from India) were reviewed to assess the fulfillment of 2022 ACR/EULAR and 1990 ACR TAK criteria. Control subjects included large-vessel giant cell arteritis (LV-GCA), large vessel vasculitis (LVV) other than TAK or GCA, or non-inflammatory arterial disorders. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratio of a positive test (LR+), likelihood ratio of a negative test (LR-), area under the receiver operating characteristics curve (AUC) at the cut-offs of ≥3 points for 1990 ACR criteria and ≥5 points for 2022 ACR/EULAR criteria were calculated. AUC was also calculated using the actual scores for the 2022 ACR/EULAR criteria. Secondary analyses were conducted on the basis of sex (male/female), using only LV-GCA as controls, using subjects ≤60 years, and stratified on age (<40, 40-60, >60 years).Results504 TAK [404 females, mean (SD) age at diagnosis 31.7 (12.6) years] and 222 controls [144 LV-GCA, 151 females, mean (SD) age at diagnosis 61.9 (15.4) years] were identified. The 2022 ACR/EULAR criteria had better sensitivity and NPV but had poorer specificity, PPV, LR+, LR-, and AUC at predetermined cut-offs than the 1990 ACR criteria (Table 1). Similar performance of 2022 ACR/EULAR criteria was observed with only LV-GCA as controls (sensitivity 95.83%, specificity 60.42%, AUC 0.781) or in subjects ≤60 years old (sensitivity 95.81%, specificity 61.90%, AUC 0.789). The 2022 ACR/EULAR criteria had a greater specificity (76.06% vs 57.62%) and AUC (0.845 vs 0.771) with similar sensitivity (93% vs 96.53%) in males than in females. Stratified for age [<40 years, n=399, 374 TAK, 25 controls; 40-60 years, n=186, 127 TAK, 59 controls; >60 years, n=141, 3 TAK, 138 controls], sensitivity remained similar (96.26%, 94.49%, 100%, respectively), whereas, specificity was higher for older age groups (52%, 66.10%, 64.49%, respectively). Cut-offs of ≥6 (sensitivity 91.87%, specificity 82.88%) and ≥7 (sensitivity 86.71%, specificity 86.49%) greatly improved balance between sensitivity and specificity (Figure 1).ConclusionIn this first validation study, the 2022 ACR/EULAR TAK criteria had poorer specificity in real-life than in the development cohort. Higher cut-offs (6 or 7) might improve the performance of these criteria. Higher PPV but lower NPV in the Indian than in the Italian cohort might reflect the different performance of the criteria in different ethnic groups.References[1]Grayson PC, et al. 2022 American College of Rheumatology/EULAR Classification Criteria for Takayasu Arteritis. Ann Rheum Dis. 2022;81(12):1654-1660.[2]Arend WP, et al. The American College of Rheumatology 1990 criteria for the classification of Takayasu arteritis. Arthritis Rheum 1990;33(8):1129-34.Table 1.Performance of the criteriaOverall (n=726, 504 TAK, 222 controls)Italian cohort (n=401, 201 TAK, 200 controls)Indian Cohort (n=325, 303 TAK, 22 controls)ACR 1990 criteriaACR EULAR 2022 criteriaACR 1990 criteriaACR EULAR 2022 criteriaACR 1990 criteriaACR EULAR 2022 criteriaSensitivity82.94%95.83%75.12%94.53%88.12%96.70%Specificity90.54%63.51%93.50%63.50%63.64%63.64%PPV95.22%85.64%92.07%72.24%97.09%97.34%NPV70.03%87.04%78.90%92.03%28.00%58.33%LR+8.772.6311.562.592.422.66LR-0.190.070.270.090.190.05AUC (95% CI)0.867 (0.842 – 0.893)0.797 (0.764 – 0.830)0.843 (0.809 – 0.878)0.790 (0.753 – 0.827)0.759 (0.654 – 0.863)0.802 (0.698 – 0.905)Correctly classified (%)85.26%85.95%84.29%79.05%86.46%94.46%Figure 1.AUC using actual 2022 ACR/EULAR scores.Disclosure of InterestsNone Declared.

BackgroundImaging role in large vessel vasculitis (LVV) patients is tremendously increased in recent years. However, the role of 18F-FDG PET in evaluating treatment response is still an unmet need.ObjectivesThe aim of the present study is to evaluate the effect of different treatment regimens, namely glucocorticoids (GC), conventional disease modifying anti-rheumatic drugs (cDMARDs) and tocilizumab (TCZ), on clinical and metabolic activity of giant cell arteritis (GCA) with extra-cranial involvement.MethodsConsecutive LVV inpatients and outpatients, classified as GCA, were prospectively enrolled. We included all patients who underwent to at least 2 consecutive 18F-FDG PET-CT or MR scan between October 2010 and October 2021. Demographic and clinical data as well as disease activity were assessed before every PET scan. Remission was defined absence of signs and symptoms attributable to GCA and normalization of ESR (<30 mm/Hr) and CRP (<1 mg/dL) [1].GCA patients were compared according to current treatment regimen: GC monotherapy versus cDMARDs (methotrexate, azathiopirine) and versus TCZ (administered both subcutaneous and intravenous). For each PET scan the vessel’s metabolic activity was evaluated using the Meller’s grading [2] and the PETVAS score [3].ResultsThe study included 47 patients (age 66 [60-70], 72.3% female) exposed to a total of 77 treatment regimens (n=37 GC monotherapy, n=26 cDMARDs, n=14 TCZ). A total of 181 PET scan were conducted (min 2 – max 6). Overall clinical remission rate during the follow-up was 75.7% in GC-treated patients, 69.2% in cDMARDs-treated and 85.7% in TCZ-treated (p=0.513).Persistence was comparable among the different treatment regimens (GC 19±10 months vs cDMARDs 22±16 months vs TCZ 23±11 months, p=0.445).All the treatment led to significant reduction of acute phase reactants (GC-treated: ESR 50vs20 mmh, p<0.001, ΔESR= -43.3%, CRP 13.6vs5.3 mg/L, p=0.001, ΔCRP= -87.7%; cDMARDs-treated: ESR 36vs27 mmh, p=0.134, ΔESR= -152%, CRP 13.6vs5.3 mg/L, p=0.038, ΔCRP= -66.3% and TCZ-treated: ESR 27vs3 mmh, p=0.017, ΔESR= -86.7%, CRP 11.4vs2.7 mg/L, p=0.023, ΔCRP= -80.2%).Significant improvement in PETVAS was observed only in TCZ-treated patients (12vs4, p=0.002, ΔPETVAS -66.7%), while the other treatment approaches resulted not significant (GC treated 12vs5, p=0.052, ΔPETVAS= -50%; cDMARDs 11vs4, p=0.124, ΔPETVAS -52.4%).Daily prednisone dose at last examination was 4.5 [0-5] mg/d in the cDMARDs group vs 1.25 [0-5] mg/d in the TCZ group (p=0.057). Interestingly, at last PET examination low-grade inflammation (Meller 1-2) was observed in 56.8% of GC-treated patients, 57.7% of cDMARDs-treated patients and 64.3% of TCZ-treated patients (p=0.884).Conclusion18F-FDG PET may be useful in assessing disease activity and monitoring response to therapy. Tocilizumab treatment significantly reduce vessel’s metabolic activity over time, when compared to conventional treatment. A persistent low-grade uptake during remission is common features in LVV patients, irrespectively of treatment regimens.References[1]Stone JH, Tuckwell K, Dimonaco S, Klearman M, Aringer M, Blockmans D, Brouwer E, Cid MC, Dasgupta B, Rech J, Salvarani C, Schett G, Schulze-Koops H, Spiera R, Unizony SH, Collinson N. Trial of Tocilizumab in Giant-Cell Arteritis. N Engl J Med. 2017 Jul 27;377(4):317-328. doi: 10.1056/NEJMoa1613849. PMID: 28745999.[2]Meller J, Grabbe E, Becker W, Vosshenrich R. Value of F-18 FDG hybrid camera PET and MRI in early takayasu aortitis. Eur Radiol. 2003 Feb;13(2):400-5. doi: 10.1007/s00330-002-1518-8. Epub 2002 Jun 29. PMID: 12599007.[3]Grayson PC, Alehashemi S, Bagheri AA, Civelek AC, Cupps TR, Kaplan MJ, Malayeri AA, Merkel PA, Novakovich E, Bluemke DA, Ahlman MA. 18 F-Fluorodeoxyglucose-Positron Emission Tomography As an Imaging Biomarker in a Prospective, Longitudinal Cohort of Patients With Large Vessel Vasculitis. Arthritis Rheumatol. 2018 Mar;70(3):439-449. doi: 10.1002/art.40379. Epub 2018 Feb 6. PMID: 29145713; PMCID: PMC5882488Figure 1.Disclosure of InterestsNone declared