Title: AB0697 Giant cell arteritis with normal inflammatory markers at diagnosis
Abstract: <h3>Background</h3> GCA is an inflamatory vasculitis affecting medium and large-sized arteries, that can result in arteritic anterior ischaemic optic neuropathy. C-reactive protein (CRP) level and erythocyte sedimentation rate (ESR) are usually elevated at GCA diagnosis, but inflammatory-marker negative disease does occur. <h3>Objectives</h3> To analyse the clinical and histological findings of patients with biopsy-proven GCA and negative inflammatory-markers at diagnosis. <h3>Methods</h3> multicenter-longitudinal retrospective study that included patients with biopsy-proven GCA recruited at 10 Hospitals from Spain (REVAS Study). Statistical analysis was performed using SPSS vs. 21. <h3>Results</h3> 418 patients: 290 (69.4%) females (ratio F/M: 2.3/1) were included. The mean age at diagnosis was 75.5±7 (53–92). The most frequent symptoms at diagnosis were recent onset headache (81%), toxic syndrome (47%) and rheumatic polymyalgia (44.5%). Jaw claudication, cranial hyperesthesia and amaurosis fugax were reported by 44.5%, 31.8% and 16.5% of patients, respectively. A total of 84 patients suffered permanent vision loss. Fourteen patients (3.3%) had normal ESR (<40 mm/h) and CRP (<5 mg/L) at diagnosis. No significant differences were found related to age at disease onset in these patients. Most patients (85%) reported headache; 42.9% jaw claudication, 28.6% cranial hyperesthesia and 42% rheumatic polymialgia. Fever was less frequent in patients with negative inflammatory-markers (7.7% vs. 40.4%, p=0.020), as well as toxic syndrome (21.4% vs. 51.5%, p=0.031). In contrast, patients with negative inflammatory-markers had more frequently amaurosis fugax (35.7% vs. 16.8%, p=0.03) and optic ischaemic neuropathy (50% vs. 18.7%, p=0.009). Temporal arteries were abnormal (thickened and/or pulse less) in 78.6% of patients with negative inflammatory-markers vs. 37% of patients with elevated ESR and/or CRP. Anaemia was less common in patients with negative inflammatory-markers (28.6% vs. 81.5%, p<0.001, mean haemoglobin 12.9±1.1 g/dL). No significant differences were found related to temporal artery biopsy findings, although patients with normal ESR and CRP showed giant cells in 74.3% of cases vs. 62%. <h3>Conclusions</h3> typically patients with GCA present with elevated inflammatory-markers (ESR and CRP) at disease onset. However, a few percentages of patients (4%–5%) have normal ESR and CPR at diagnosis.<sup>1</sup> In our series, 3.3% of patients had negative inflammatory-markers at diagnosis. These patients had fewer constitutional symptoms and more visual symptoms (amaurosis fugax and permanent visual loss) than patients with elevated ESR and/or CRP. Our result are similar to those published in the laiterature. Abnormal temporal arteries on physical examination may help to diagnosis <h3>Reference</h3> [1] Utility of Erithrocyte sedimentation rate and C-reactive protein for the diagnosis of Giant Cell arteritis. Semin Arthrithis Rheum2012;41:866–71 <h3>Disclosure of Interest</h3> None declared