POS0797 LARGE VESSEL-GCA: A DIAGNOSTIC CHALLENGE
Authors: F. Regola, F. Franceschini, G. Bosio, P. Toniati
Journal: Annals of the Rheumatic Diseases (2021)

Background: GCA is the most frequent systemic vasculitis in patients older than 50 years involving medium-sized and large arteries. Inflammation of the extracranial branches of the carotid artery gives rise to the classic symptoms of GCA. However, in almost two-thirds of patients GCA involves also the aorta and its major branches (1,2). Large vessel involvement leads to a different atypical clinical picture which can be challenging to diagnose (3,4). More information on clinical presentation and vessel involvement in large-vessel GCA are needed to better diagnose it. Objectives: To analyze clinical presentation of large-vessel GCA compared to classical cranial disease. Methods: 100 consecutive patients with a clinical diagnosis of GCA were enrolled in this retrospective study. All patients were older than 50 years of age, met the ACR criteria for GCA or had a positive biopsy of the temporal artery or evidence of large vessel vasculitis at FDG-PET/CT scan. Results: Based on vascular involvement, patients were classified into three group: 61 patients with only cranial arteritis (C-GCA), 16 patients with only extracranial large vessel vasculitis (LV-GCA) and 23 patients with both cranial and large vessel involvement (LV-C-GCA). Compared to C-GCA, patients with large vessel involvement (LV-GCA and LV-C-GCA) were younger and more frequently women, and the difference was further significant for patients with isolated LV-GCA. Patients with isolated LV-GCA had also the longer duration of symptoms at GCA diagnosis [LV-GCA 20(16-82) vs LV-C-GCA 12(4-16) vs C-GCA 4(3-12) weeks; p&lt;0.001]. Systemic symptoms, as fever and fatigue, were associated with large vessel involvement, both in LV-GCA and LV-C-GCA groups. Polymyalgia rheumatica was equally reported in all three cohorts of patients and no significant differences were found in inflammatory markers levels according to vessel involvement. In patients with large vessels involvement (LV-GCA and LV-C-GCA) thoracic aorta, subclavian arteries and abdominal aorta were the most frequently involved arteries. Conclusion: GCA is not a single entity but includes several patterns of disease. Female gender, younger age and systemic symptoms are associated with large vessel involvement, regardless the presence or absence of cranial symptoms. The different clinical manifestations of large vessel GCA lead to a longer time to diagnosis if compared to C-GCA. For these reasons, in patients with the aforementioned characteristics, a large vessel involvement should be considered in order to reduce the time to diagnosis. References: [1]De Boysson H, et al. Clin Exp Rheumatol 2019. [2]Prieto-González S, et al. Ann Rheum Dis 2012. [3]Brack A, et al. Arthritis Rheum 1999. [4]Muratore F, et al. Rheumatol 2015. GCA (n: 100) C-GCA (n: 61) LV-C-GCA (n: 23) LV-GCA (n: 16) p Age: median (IQR) 76 (67-79) 75 (71-80) 74 (69-77) 63 (59-72) 0.001 Female/ Male 68 (68%) / 32 (32%) 38 (62%) / 23 (38%) 17 (74%) / 6 (26%) 13 (81%) / 3 (19%) 0.276 Time between symptom onset and diagnosis (weeks) 8 (4-20) 4 (3-12) 12 (4-16) 20 (16-82) &lt;0.001 Cranial symptoms (overall) 84 (84%) 61 (100%) 23 (100%) 0 (0%) &lt;0.001 New temporal headache 77 (77%) 58 (95%) 19 (83%) 0 (0%) &lt;0.001 Visual symptoms 39 (39%) 34 (56%) 5 (22%) 0 (0%) &lt;0.001 Jaw or tongue claudication 35 (35%) 27 (44%) 8 (35%) 0 (0%) 0.004 Fever 48 (48%) 23 (38%) 14 (61%) 11 (69%) 0.032 Fatigue 75 (75%) 40 (66%) 21 (91%) 14 (88%) 0.023 Weight loss 52 (52%) 28 (46%) 13 (57%) 11 (69%) 0.235 Polymyalgia rheumatica 43 (43%) 27 (44%) 13 (57%) 3 (19%) 0.061 Arm or leg claudication 5 (5%) 0 (0%) 4 (17%) 1 (6%) 0.005 CRP (C-reactive protein) 83 (45-127) 77 (39-115) 89 (50-134) 95 (20-124) 0.461 ESR (erythrocyte sedimentation rate) 72 (47-96) 70 (46-88) 75 (28-105) 66 (44-91) 0.711 Cranial arteries 84 (84%) 61 (100%) 23 (100%) 0 (0%) &lt;0.001 Carotid arteries 19 (19%) 0 (0%) 12 (52%) 7 (44%) &lt;0.001 Subclavian and upper limb arteries 21 (21%) 0 (0%) 10 (43%) 11 (69%) &lt;0.001 Thoracic aorta 29 (29%) 0 (0%) 15 (65%) 14 (88%) &lt;0.001 Abdominal aorta 21 (21%) 0 (0%) 10 (43%) 11 (69%) &lt;0.001 Iliac and inferior limb arteries 10 (10%) 0 (0%) 6 (26%) 4 (25%) &lt;0.001 Disclosure of Interests: None declared