AB0583 100 GCA REFERRALS TO A TERTIARY CARE CENTRE: INFLAMMATION, HEADACHES AND CPAP MASKS
Authors: Jobie Evans, Natasha Jordan
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> Giant cell arteritis (GCA) is a large vessel vasculitis typically affecting patients above the age of 50 years. It is the most common cause of vasculitis affecting adults with a UK prevalence of approximately 0.25% of the population above the age of 55 years [1]. Whilst its clinical presentation can often be non-specific, if left undiagnosed it can lead to devastating visual impairment. However, this has to be balanced with the potential for corticosteroid related adverse effects. The threshold for suspected diagnosis and referral to rheumatology centres from the community and acute medical services is therefore low, leading to a relatively high number of referrals with a wide range of clinical features and potential differential diagnoses. <h3>Objectives:</h3> To assess the referral characteristics, demographics, management, corticosteroid adverse effects and differential diagnosis of 100 consecutive patients referred with suspected GCA to a tertiary rheumatology centre. <h3>Methods:</h3> The notes of 100 consecutive patients referred to the rheumatology department at Addenbrookes hospital between August 2016 and January 2018 with suspected GCA were reviewed. Information on patient demographics, comorbidities, presenting symptoms, availability of up to date inflammatory markers, dates of treatment and clinic review, temporal artery biopsy (TAB) date and result, diagnosis and corticosteroid adverse effects were retrieved. <h3>Results:</h3> Seventy three female and twenty seven male patients (average age 72.3 years) were referred within the time period. General practice referred 69% of the cases and common comorbidities included hypertension and type II diabetes. The most common symptoms were headache (97%), scalp tenderness (79%), jaw claudication (35%) and polymyalgia symptoms (34%). Up to date inflammatory markers were available for 91% of referrals and 92% were commenced on corticosteroids before or at the time of referral with an average starting dose of 43.9mg oral prednisolone. A TAB was performed on 85% of patients, with an average time of 9 days between referral and TAB and 40 days between referral and clinic appointment. TAB was positive for GCA in 13/85 patients. Temporal artery ultrasound (TAU) was not available at our centre. The American College of Rheumatology (ACR) classification criteria for GCA were met by 85% of the patients, but only 69% were given a diagnosis of GCA. Other diagnoses included trigeminal neuralgia, temporo-mandibular dysfunction, toothache and a poorly fitted CPAP mask. Corticosteroid adverse effects were experienced by 45% of patients including weight gain, poorly controlled diabetes, mood and sleep disturbance, and 4% suffered severe complications requiring hospital admission (pneumonia, disseminated nocardia infection and two episodes of upper gastrointestinal bleed). <h3>Conclusion:</h3> Suspected GCA is a common referral to rheumatology but the non-specific symptoms, quality of referral and potential for visual loss can lead to over-diagnosis. We have found the majority of our referrals to have been appropriate and complete with 85% meeting ACR criteria for GCA and 92% having up to date inflammatory markers. Despite this, 31% of patients received an alternative diagnosis. Increasing the availability of TAU may improve the time to diagnosis and therefore potentially reduce unnecessary exposure to corticosteroids. Our experience highlights the fact that despite a good standard of referral, GCA remains a difficult condition to diagnose and poses an on-going challenge to the rheumatologist. <h3>References</h3> [1] Yates, M., et al., The prevalence of giant cell arteritis and polymyalgia rheumatica in a UK primary care population. BMC Musculoskelet Disord, 2016. 17: p. 285. <h3>Disclosure of Interests:</h3> Jobie Evans Grant/research support from: I am currently working on a MD research project looking at the use of magnetic resonance enterography imaging as a screening tool for axial spondyloarthritis in patients with Crohn's disease. This study is commercially funded by Merck, Sharp and Dohme corporation (MSD)., Natasha Jordan: None declared