E043 Fast track giant cell arteritis service in a district general hospital using ultrasound doppler imaging
Authors: Kamperidis Panagiotis , Hall Andrea , Perera Hasanthi , Panthakalam Sam 
Published: April 2024

Abstract

Background/Aims
Giant cell arteritis (GCA) is the commonest large and medium artery vasculitis, a multisystem condition that results in significant comorbidity and mortality. Corticosteroids are pivotal in remission induction and maintenance therapy, but complications can arise either due to delayed treatment, or unnecessary treatment of GCA mimics. This renders quick diagnosis of GCA vital. Temporal artery biopsy (TAB) has traditionally been the golden standard diagnostic modality, but it requires a surgical setting, resulting in delays. Temporal artery ultrasound doppler scanning (TA UDS), however, has now been incorporated by both BSR and EULAR in their recommendations, offering a diagnostic tool with high specificity and sensitivity.

Aims
1. To set up a fast track GCA diagnostic service in an one-stop-shop outpatient clinical setting with inhouse ultrasound; 2. To limit dependence of GCA diagnosis on TAB

Methods
We set up a dedicated GCA clinic at Eastbourne District General Hospital aiming to see patients within five days of referral. In the clinic, patients were categorised to low, moderate or high GCA risk via a pre-test probability score, and had TA UDS by an expert rheumatologist. We collected data on number of UDS performed, scan outcomes, and TAB requests over a 17-month period.

Results
Total number of referrals with suspected GCA was 147, mainly via general practice and ophthalmology, with 117 already having been started on corticosteroids by the referrer. Overall, 93% of patients were seen within five days of initial referral, with 32% within 72 hours of steroid commencement. We scanned 138 patients (94%) and diagnosed GCA in 41 (30%) of them. Of the nine we did not scan, six had very low probability score and were given alternative diagnoses; two were out of the window for diagnostics and GCA was diagnosed clinically; and one could not be scanned due to technical reasons, so a TAB was requested. Crucially, this was the only TAB requested during this period.

Conclusion
Our fast track service has facilitated prompt review of GCA referrals with the use of ultrasound, limiting the need for a TAB. The pathway enables both prompt commencement of appropriate steroid-weaning regimens in confirmed GCA, but also facilitates timely discontinuation of corticosteroids in patients with excluded GCA, thus minimising future complications either way. Typically, it takes more than three weeks to arrange a TAB. Moreover, ultrasound use avoids an invasive procedure with potential for surgical complications. From a healthcare system point of view, there are certain cost-saving implications in using ultrasound for GCA diagnosis. These can range from reduced demand for outpatient clinics, theatre slots and theatre staff, to minimisation of any future complications be it post-op, disease- or steroid- related. Finally, a service user survey, aiming to improve our pathway, documented improved patient satisfaction.

Disclosure
P. Kamperidis: None. A. Hall: None. H. Perera: None. S. Panthakalam: None.