P189 Giant cell arteritis: audit of a fast-track assessment pathway including the use of positron emission tomography-computed tomography as an early diagnostic tool

Abstract Background/Aims Giant cell arteritis (GCA) is a large and medium-vessel vasculitis requiring timely diagnosis and management. Our hospital has employed a fast-track pathway (FTP) for suspected GCA since 2019, including the use of positron emission tomography-computed tomography (PET-CT) as an early diagnostic tool. Methods Retrospective analysis of electronic records for patients referred to rheumatology at University College London Hospitals with suspected GCA between June 2023 and December 2024. Outcomes were compared to the British Society for Rheumatology audit tool standards for suspected GCA. Results 21 patients were referred with suspected GCA with a mean age of 73 years. 76% of patients were female. There were 13 confirmed GCA cases. Main presenting features included headache (71%), scalp tenderness (52%), visual symptoms (48%), jaw claudication (33%) and fever (5%). All patients were reviewed within 3 days of referral, with 95% reviewed by the next day. All were started on corticosteroids and had FBC and ESR sent. All patients presenting with visual symptoms were appropriately started on high-dose steroids and reviewed by ophthalmology, with 60% having same-day reviews. All patients underwent confirmatory testing. Only 1 patient had temporal artery biopsy (TAB), which was negative. 95% of patients had temporal artery ultrasound (TAUS), of which 11% were positive. 76% of patients had PET-CT, of which 56% were positive. 7 patients (33%) had a negative TAUS but positive PET-CT. The mean steroid course prior to scans was 4.2 days for TAUS and 4.5 days for PET-CT. 95% of patients commencing high-dose steroids had baseline blood sugar checked and 75% had vitamin D checked. 70% either had a DEXA in the last 5 years or one done soon after starting steroids. 85% commenced vitamin D therapy and 60% were recommended to start bisphosphonates. Of confirmed GCA patients, 54% had formally documented written information and 77% had documented safety-netting advice. Conclusion The FTP resulted in excellent referral-to-review time, appropriate steroid initiation, further investigations and consideration of steroid side effects. PET-CT was valuable in identifying 54% of cases that were TAUS negative. The use of PET-CT has superseded the need for TAB. Since the establishment of the FTP 4 years ago, the number of TABs had declined by 87.5%1. In this study only 4.8% of patients underwent TAB (lowest since the start of the FTP). Negative PET-CT also helped to allow steroids to be discontinued quickly in non-GCA patients, reducing risks associated with long-term steroid use. The study highlights the utility of PET-CT and centres with access to PET-CT should consider its use to facilitate early diagnosis and reduce the need for invasive biopsies. Disclosure A. Ghosh: None. V. Morris: None. S. Voo: None. D.R. Ludwig: None.