Temporal Artery Biopsy Research Articles

Signal Regulatory Protein α Expression in Systemic Vasculitis.

Signal regulatory protein α (SIRPα) is found primarily on myeloid cells, including macrophages and neutrophils; binds to CD47; and regulates phagocytosis, antigen presentation, cellular fusion, cell proliferation, and migration. Therefore, SIRPα may be involved in the pathogenesis of autoimmune diseases, including systemic vasculitis. This study aimed to assess SIRPα expression in tissue samples from patients with vasculitis. Immunohistochemical staining for SIRPα was performed on temporal artery (TA), kidney, and lung biopsy samples from patients with giant cell arteritis (GCA), patients with microscopic polyangiitis (MPA), patients with granulomatosis with polyangiitis (GPA), and patients without vasculitis. A score of SIRPα+ expression was calculated, derived from the percentages of monocytes, macrophages, and dendritic cells and neutrophils with different staining intensities in affected tissues. A total of 46 samples from patients with different vasculitides (GCA, MPA, and GPA) were included in the study. Tissue samples included TA samples from 15 patients with GCA; kidney samples from 11 and 9 patients with GPA and MPA, respectively; and lung samples from 11 patients with GPA. Most tissue samples from patients with active vasculitis (15 of 15 TA samples, 17 of 20 kidney samples, and 9 of 11 lung samples) showed SIRPα staining. SIRPα staining intensity was less in kidney samples compared to TA and lung samples. This study demonstrates high-level expression of SIRPα in macrophages and monocytes in affected tissue in systemic vasculitis. These findings provide a foundation for further studies exploring the role of the SIRPα-CD47 pathway in the pathogenesis of systemic vasculitis and the potential for the blockade of SIRPα and/or the depletion of SIRPα+ cells as treatment of systemic vasculitis.

Ultrasound for the Diagnosis of Giant Cell Arteritis.

Giant cell arteritis (GCA) is the most frequent large vessel primary vasculitis in the elderly. Correct diagnosis and fast assessment are necessary to prevent complications as well as unnecessary treatments. Giant cell arteritis can present as classical cranial symptoms or as extracranial disease. Although temporal artery biopsy is still the gold standard, ultrasound (US) is gaining ground on evidence with good diagnostic performance as a first approach to support the clinical criteria. The "halo" sign is the most characteristic finding and should be a requisite for reporting an US assessment for GCA with a 43%- 77% sensitivity and 89%-100% specificity, when compared to American College of Rheumatology 1990 criteria. Ultrasound is a cost-effective, noninvasive test that offers bed-side results. The need for an experienced sonographer and consensus on the methodology and interpretation of US is fundamental to reduce operator-dependent errors. The diagnostic US algorithm for GCA depends on the clinical scenarios, and in some cases it may be enough to confirm or discard the GCA diagnosis. We review procedure details for cranial and extracranial arteries and technical requirements.

Coronal Approach (Cadaver)

For treatment of facial trauma such as a frontal sinus fracture, orbital fractures, or zygoma fractures, the coronal or bi-temporal approach is used. The approach can also be used for superficial temporal artery biopsy. This approach exposes the anterior cranial vault, forehead, and upper and middle regions of the facial skeleton including the zygomatic arch. It provides access to these areas with minimal complications and cosmetically acceptable hidden scars. The subperiosteal or subgaleal planes are commonly used for coronal flap dissection. Here, we present a demonstration of the coronal approach to exposing the upper or middle facial skeleton in a cadaver.

Mönckeberg calcification in a temporal artery

Mönckeberg’s calcification is a disease of low prevalence and unknown etiology that causes calcification of the middle layer of medium and small arteries. It usually presents with a clinical picture similar to giant cell arteritis, so a differential diagnosis with similar entities should be made. The diagnosis is anatomopathological, and there is no treatment that has shown significant results. Herein, we present the case of a 74-year-old male patient with recurrent syncope and chest pain, in whom giant cell arteritis was suspected and a temporal artery biopsy was taken with the incidental finding of calcification of Mönckeberg’s media. Key words: Calcification, Arteritis, Giant cell, Mönckeberg

The Spectrum of Isolated Retinal Artery Occlusion Secondary to Giant Cell Arteritis.

We systematically reviewed the literature to investigate the clinical features of isolated arteritic retinal artery occlusion (A-RAO) associated with giant cell arteritis (GCA). The four primary types of A-RAO were central retinal artery occlusion (CRAO), hemi-central retinal artery occlusion (hCRAO), branch retinal artery occlusion (BRAO), and cilioretinal artery occlusion (CLRAO). The most reported presentation was unilateral CRAO, followed by bilateral CRAO, unilateral CLRAO, and bilateral BRAO. Most RAOs were accompanied by typical GCA signs and symptoms, which can help distinguish them from non-arteritic RAOs. When reported, temporal artery biopsy confirmed GCA in most cases. Patients with GCA may present with a broad spectrum of isolated unilateral and bilateral A-RAOs. [Ophthalmic Surg Lasers Imaging Retina 2024;55:536-540.].

Histopathology reporting of temporal artery biopsy specimens for giant cell arteritis: results of a modified Delphi study

The temporal artery biopsy (TAB) is regarded as the gold-standard test in the diagnosis of giant cell arteritis (GCA). There is a lack of agreement among experienced pathologists regarding the...

Altered Plasma Levels and Tissue Expression of Fibroblast Activation Protein Alpha in Giant Cell Arteritis.

Giant cell arteritis (GCA) is characterized by granulomatous inflammation of the medium- and large-sized arteries accompanied by remodeling of the vessel wall. Fibroblast activation protein alpha (FAP) is a serine protease that promotes both inflammation and fibrosis. Here, we investigated the plasma levels and vascular expression of FAP in GCA. Plasma FAP levels were measured with enzyme-linked immunosorbent assay in treatment-naive patients with GCA (n = 60) and polymyalgia rheumatica (PMR) (n = 63) compared with age- and sex-matched healthy controls (HCs) (n = 42) and during follow-up, including treatment-free remission (TFR). Inflamed temporal artery biopsies (TABs) of patients with GCA (n = 9), noninflamed TABs (n = 14), and aorta samples from GCA-related (n = 9) and atherosclerosis-related aneurysm (n = 11) were stained for FAP using immunohistochemistry. Immunofluorescence staining was performed for fibroblasts (CD90), macrophages (CD68/CD206/folate receptor beta), vascular smooth muscle cells (desmin), myofibroblasts (α-smooth muscle actin), interleukin-6 (IL-6), and matrix metalloproteinase-9 (MMP-9). Baseline plasma FAP levels were significantly lower in patients with GCA compared with patients with PMR and HCs and inversely correlated with systemic markers of inflammation and angiogenesis. FAP levels decreased even further at 3 months on remission in patients with GCA and gradually increased to the level of HCs in TFR. FAP expression was increased in inflamed TABs and aorta of patients with GCA compared with control tissues. FAP was abundantly expressed in fibroblasts and macrophages. Some of the FAP+ fibroblasts expressed IL-6 and MMP-9. FAP expression in GCA is clearly modulated both in plasma and in vessels. FAP may be involved in the inflammatory and remodeling processes in GCA and have utility as a target for imaging and therapeutic intervention.

Identification of two autoantigens recognised by circulating autoantibodies as potential biomarkers for diagnosing giant cell arteritis.

Giant cell arteritis (GCA) is a common vasculitis affecting patients aged 50 and older. GCA leads to chronic inflammation of large/medium-sized vessel walls with complications such as permanent vision loss and risk of stroke and aortic aneurysms. Early diagnosis is crucial and relies on temporal artery biopsy (TAB) and ultrasound imaging of temporal and axillary arteries. However, these methods have limitations. Serum biomarkers as autoantibodies have been reported but with inconclusive data for their use in the clinical setting. Additionally, C-reactive protein and erythrocyte sedimentation rate are non-specific and limited in reflecting disease activity, particularly in patients treated with IL-6 inhibitors. This study aimed to identify serum autoantibodies as new diagnostic biomarkers for GCA using a human protein array. One commercial and one proprietary human protein array were used for antibody profiling of sera from patients with GCA (n=55), Takayasu (TAK n=7), and Healthy Controls (HC n=28). The identified candidate autoantigens were purified and tested for specific autoantibodies by ELISA. Antibodies against two proteins, VSIG10L (V-Set and Immunoglobulin Domain Containing 10 Like) and DCBLD1 (discoidin), were identified and found to be associated with GCA, with an overall prevalence of 43-57%, respectively, and high specificity as individual antibodies. A control series of TAK sera tested negative. Detecting GCA-specific autoantibodies may offer a new, non-invasive tool for improving our diagnostic power in GCA. Even though cell-mediated immune responses are crucial for GCA pathogenesis, this finding opens the way for investigating the additional role of humoral immune responses in the disease.

Diagnostic Strategy Using Color Doppler Ultrasound of Temporal Arteries in Patients With High Clinical Suspicion of Giant Cell Arteritis : A Prospective Cohort Study.

Giant cell arteritis (GCA) is the most prevalent systemic vasculitis in people older than 50 years. Any delay in diagnosis impairs patients' quality of life and can lead to permanent damage, particularly vision loss. To evaluate a diagnostic strategy for GCA using color Doppler ultrasound of the temporal artery as a first-line diagnostic test, temporal artery biopsy (TAB) as a secondary test, and physician expertise as the reference method. Prospective multicenter study with a 2-year follow-up. (ClinicalTrials.gov: NCT02703922). Patients were referred by their general practitioner or ophthalmologist to a physician with extensive experience in GCA diagnosis and management in one of the participating centers: 4 general and 2 university hospitals. 165 patients with high clinical suspicion of GCA, aged 79 years (IQR, 73 to 85 years). The diagnostic procedure was ultrasound, performed less than 7 days after initiation of corticosteroid therapy. Only ultrasound-negative patients underwent TAB. Bilateral temporal halo signs seen on ultrasound were considered positive. Ultrasound and TAB results were compared with physician-diagnosed GCA based on clinical findings and other imaging. Diagnosis of GCA was confirmed in 44%, 17%, and 21% of patients by ultrasound, TAB, and clinical expertise and/or other imaging tests, respectively. Their diagnosis remained unchanged at 1 month, and 2 years for those with available follow-up data. An alternative diagnosis was made in 18% of patients. The proportion of ultrasound-positive patients among patients with a clinical GCA diagnosis was 54% (95% CI, 45% to 62%). Small sample size, no blinding of ultrasound and TAB results, lack of an objective gold-standard comparator, and single diagnostic strategy. By using ultrasound of the temporal arteries as a first-line diagnostic tool in patients with high clinical suspicion of GCA, further diagnostic tests for patients with positive ultrasound were avoided. Tender "Recherche CH-CHU Poitou-Charentes 2014."

Effectiveness Of Tocilizumab In Aortitis And Aneurysms Associated With Giant Cell Arteritis

ObjectiveAortitis in Giant Cell Arteritis (GCA-aortitis) is a frequent complication that may lead to aneurysms. Tocilizumab (TCZ) was approved in GCA, but the efficacy in GCA-aortitis and aneurysms has not been analyzed to date. Our aim was to assess the effectiveness and safety of TCZ in a wide series of GCA-aortitis and aneurysms. MethodsMulticentre observational study with GCA-aortitis treated with TCZ. GCA was diagnosed by: a) ACR criteria, b) temporal artery biopsy, and/or c) imaging techniques. Aortitis was diagnosed mainly by PET/CT. Main outcomes were EULAR and imaging remission. Others were clinical remission, analytical normalization, corticosteroid-sparing effect, and the prevention and improvement of aneurysms. Results196 patients with GCA-aortitis treated with TCZ. After 6 months, 72.2% reached EULAR remission but only 12% an imaging remission; increasing up-to 81.4% and 31.8%, respectively, at 24 months. A rapid clinical remission, ESR and CRP normalization was observed in 47.4%, 84.3% and 55.6%, at 1 month, increasing to 89.6%, 85.3% and 80.3% at 24 months, respectively.Aneurysms were present in 10 (5%) patients. Five of them required early surgery, while 3 others enlarged. No patient on TCZ therapy developed aneurysms during follow-up. ConclusionIn patients with GCA-aortitis treated with TCZ, a rapid and maintained clinical and analytical improvement was observed. However, there was an uncoupling between clinical and EULAR remission with imaging remission.

Temporal Artery Biopsy Does Not Lead to Shorter Steroid Duration in Patients With Suspected Giant Cell Arteritis

Temporal Artery Biopsy Does Not Lead to Shorter Steroid Duration in Patients With Suspected Giant Cell Arteritis

Risk loci involved in giant cell arteritis susceptibility: a genome-wide association study

Giant cell arteritis is an age-related vasculitis that mainly affects the aorta and its branches in individuals aged 50 years and older. Current options for diagnosis and treatment are scarce, highlighting the need to better understand its underlying pathogenesis. Genome-wide association studies (GWAS) have emerged as a powerful tool for unravelling the pathogenic mechanisms involved in complex diseases. We aimed to characterise the genetic basis of giant cell arteritis by performing the largest GWAS of this vasculitis to date and to assess the functional consequences and clinical implications of identified risk loci. We collected and meta-analysed genomic data from patients with giant cell arteritis and healthy controls of European ancestry from ten cohorts across Europe and North America. Eligible patients required confirmation of giant cell arteritis diagnosis by positive temporal artery biopsy, positive temporal artery doppler ultrasonography, or imaging techniques confirming large-vessel vasculitis. We assessed the functional consequences of loci associated with giant cell arteritis using cell enrichment analysis, fine-mapping, and causal gene prioritisation. We also performed a drug repurposing analysis and developed a polygenic risk score to explore the clinical implications of our findings. We included a total of 3498 patients with giant cell arteritis and 15 550 controls. We identified three novel loci associated with risk of giant cell arteritis. Two loci, MFGE8 (rs8029053; p=4·96 × 10-8; OR 1·19 [95% CI 1·12-1·26]) and VTN (rs704; p=2·75 × 10-9; OR 0·84 [0·79-0·89]), were related to angiogenesis pathways and the third locus, CCDC25 (rs11782624; p=1·28 × 10-8; OR 1·18 [1·12-1·25]), was related to neutrophil extracellular traps (NETs). We also found an association between this vasculitis and HLA region and PLG. Variants associated with giant cell arteritis seemed to fulfil a specific regulatory role in crucial immune cell types. Furthermore, we identified several drugs that could represent promising candidates for treatment of this disease. The polygenic risk score model was able to identify individuals at increased risk of developing giant cell arteritis (90th percentile OR 2·87 [95% CI 2·15-3·82]; p=1·73 × 10-13). We have found several additional loci associated with giant cell arteritis, highlighting the crucial role of angiogenesis in disease susceptibility. Our study represents a step forward in the translation of genomic findings to clinical practice in giant cell arteritis, proposing new treatments and a method to measure genetic predisposition to this vasculitis. Institute of Health Carlos III, Spanish Ministry of Science and Innovation, UK Medical Research Council, and National Institute for Health and Care Research.

Parietal branch of the superficial temporal artery: An underutilized biopsy site

Purpose: Giant cell arteritis (GCA) is an immune-mediated vasculitis that can lead to significant symptoms and disease sequelae such as headaches, fevers, weight loss, jaw pain, optic neuropathy with permanent vision loss, and stroke. The gold standard for diagnosis of GCA is a temporal artery biopsy (TAB) as it has a high specificity and sensitivity. The TAB is commonly harvested from the frontal branch of the superficial temporal artery, however given its location, there are potentially significant consequences including facial nerve injury and poor cosmetic outcomes. An alternative to this method is biopsy of the parietal branch, as it reduces the risk of facial nerve injury and comfortably hides the scar line within the hair of most patients. Results: We describe in detail our department's TAB technique and experience from pre-procedure preparation to post-procedure care. Conclusion: The parietal branch TAB is a typically underutilised, well tolerated and viable alternative to the frontal branch TAB and it may be considered in the first instance to reduce the risk of complications.

P032 Designing a workshop for a temporal artery biopsy simulation

Abstract Background/Aims A temporal artery biopsy (TAB) is performed to confirm a diagnosis of giant cell arteritis (GCA) and it is recommended by clinical practice guidelines. Historically there have been limited opportunities to perform this procedure and teaching has been largely informal and non standardised. This impacts a trainee’s confidence and competence and potentially patient safety. Simulation is crucial in modern day surgical education and so we designed, organised and delivered a wetlab to teach the steps of TAB to address these issues. Methods The event took place at the Welsh Institute for Minimal Access Therapy (WIMAT) centre in Cardiff. The WIMAT team developed the TAB models to be used. The event covered all of the theoretical aspects of performing a TAB, a demonstration on how to map the temporal artery, how to perform an ultrasound doppler procedure to locate the temporal artery and finally hands on experience performing a TAB with two different complexity models. Participants were asked to complete a 30 item Google Forms Questionnaire to help us to evaluate pre and post session knowledge, understanding and learning experiences pertaining to TAB. Results Participants noted significant improvements in their knowledge and understanding pertaining to all domains covered. A lack of knowledge, a lack of procedures previously performed, concern about damaging the facial nerve and lack of senior support/supervision were all identified as reasons as to why trainees get apprehensive when it comes to performing a TAB. Conclusion This novel formal teaching event provides a blueprint for deaneries to use in their teaching of TAB’s which can benefit trainees and patients. Modern surgical education benefits from wetlabs with expert supervision. Our findings also emphasise the benefits of cross specialty collaborative work. Disclosure S. Rehan: None. P. Watts: None. I. Williams: None. P. Hennessy: None. C. O’Flaherty: None. A. Haridas: None.

E043 Fast track giant cell arteritis service in a district general hospital using ultrasound doppler imaging

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.

P190 Protocolised ultrasonography led pathway has a high sensitivity for diagnosis of primary large vessel vasculitis

Abstract Background/Aims Ultrasonography (US) for diagnosis of large vessel vasculitis (LVV) is a recommended first line diagnostic procedure. Our county has an annual incidence of 57.5/million for primary LVV (giant cell arteritis (GCA) 48.3/million; Takayasu 2.5/million; unclassified LVV 6.4/million). Our protocolised fast-track US pathway has reduced visual loss from 18.7% to 11.5%. We present the results of our first 1000 unique referrals. Methods Unique requests for US from January 2017 were analysed. Protocolised US examination of the arteries includes superficial temporal artery (STA) and its rami, followed by the entire axillary artery, followed by other arteries as necessary. Halo sign in at least two different arteries was needed for diagnosis of LVV. A temporal artery biopsy (TAB) or positron emission tomography (PET) were requested if the US was negative AND CRP was ≥20mg/L (or missing) AND an alternate explanation for the raised CRP was not immediately apparent. For those where a second test was not requested OR if it was negative, prednisolone was tapered rapidly, and a patient-initiated follow-up allowed rapid re-assessment. If referring physician or patient did not want a second test, GCA was diagnosed on clinical grounds alone and the pathway was considered to have failed. Results Median age was 73 (IQR 13); 11/1000 referrals were for people <50 years of age. The median delay for the procedure was 4 (IQR 4) days. Prednisolone had been started a median of 4 (IQR 5) days previously. 279/1000 (28%) US scans demonstrated vasculitis. Pre-steroid CRP was ≥20mg/L in 283 cases and unavailable in 7. An alternate explanation for the raised CRP was found in 102 cases, 181 were referred for a second test, and 7 received a clinical diagnosis of GCA without a second test. The second test was diagnostic in 31/181 (17%) - 24/139 (17%) TAB, 7/42 (17%) PET. 3/150 cases with a negative second test and 4/431 cases with CRP <20mg/L were diagnosed with GCA on patient-initiated follow-up. The delayed diagnosis did not result in visual loss. 202/279 (72%) US positive cases had bilateral STA involvement. The addition of axillary artery imaging picked up a further 53 (19%) cases; 24/279 (9%) cases needed imaging of other arteries. The sensitivity and negative predictive value of the pathway are 96% (310/324) and 98% (683/690) respectively. Conclusion Our protocolised US led pathway for diagnosis of LVV is highly sensitive and allows disease exclusion with high certainty. Routine US of the superficial temporal artery and its rami, and the entire axillary artery provide diagnosis in 91% of cases but ability to scan more arteries improves yield in a further 9% of cases. Composite testing with US plus second test, stratified by CRP levels, can be recommended as a gold standard diagnostic tool for LVV. Disclosure C.B. Mukhtyar: None. G. Ducker: None. C. Beadsmoore: None. K. Sisson: None. C. Jones: None.

E023 Intimomedial mucoid degeneration. A rare vascular disease mimicking giant cell arteritis presentation

Abstract Background/Aims The accuracy of giant cell arteritis (GCA) diagnosis has greatly improved in recent years with increasing use of fast track clinics and vascular ultrasound. The “halo” sign is recognised as confirmation of a positive test and is considered virtually pathognomonic of GCA in the setting of a correlating clinical presentation. There are caveats to this and “false halos” have been reported associated with arterial thickening seen in other conditions including atherosclerosis and lymphoma. In this case a focal area of arterial wall thickening mimicking a halo on ultrasound was due to a rare vascular condition called intimomedial mucoid degeneration. Methods A 63 year old female presented via the direct assessment unit to the fast track GCA service. She reported an 8 week history of a tender right forehead lump and a 3 week history of associated new headache with marked tenderness at the site of the lump. The headache was severe and had become persistent. Mild shoulder stiffness was present. No jaw claudication. Blurring while wearing glasses noted but no definite visual change. CRP 2mg/L, ESR at usual baseline of 30mm/hr. Other indices normal. On examination: No shoulder restriction. No visual field deficit. Palpable pulsatile area of artery right side of forehead that was exquisitely tender with less marked tenderness of the artery adjacent to this. No symptoms on left side. GCA probability score (GCAPS) 10 indicating intermediate probability of GCA. Results Temporal artery ultrasound performed using GE Logiq e and 10-22mHz probe. Left side imaged entirely normally. Right side symptomatic area imaged as a focal asymmetric thickened area of frontal branch artery measuring 1.5mm maximally in compression. The frontal branch artery imaged normally proximal and distal to this as did the right common superficial and parietal branches. Features were unusual however she was commenced on prednisolone 40mg daily pending further investigations. Eye assessment detected no ischaemic concerns. She returned for reassessment after 4 days. There was some symptomatic improvement however the tender lump persisted. A second opinion on the ultrasound was sought from the interventional radiologist, who felt the focal area may be a lymph node, with thickened artery adjacent. Surgical exploration and temporal artery biopsy was subsequently performed. Conclusion Histology showed there was actually mucoid change with eccentric thickening of the artery with aneurysmal change in keeping with the rare diagnosis of intimomedial mucoid degeneration. This is a very rare condition which causes predisposition to arterial aneurysm formation, and typically presents with acute pain of the artery involved. This lady had developed an aneurysm which was excised at the time of the biopsy, relieving her symptoms. This case is a reminder to pursue additional investigations and tissue diagnosis in the setting of unusual clinical and imaging findings. Disclosure S. Black: None. M. Wray: None. H. Stewart: None. E. Durkan: None. V. Serafimov: None. P. Davey: None. L. Smith: None.

P003 A fast track giant cell arteritis pathway incorporating ultrasonography improves service provision in a District General Hospital

Abstract Background/Aims Giant cell arteritis (GCA) is the most common form of adult vasculitis with comorbidities including blindness. Early identification and initiation of treatment is therefore essential. The 2020 BSR guideline suggests specialist review within three days of suspected GCA. In Ipswich Hospital, there was previously no universal referral pathway for GCA. Patients were referred to the acute medicine, A&E, rheumatology or ophthalmology clinics. An audit in 2018 over 18 months highlighted a significant delay in specialist reviews. In 2021 we designed a rapid access referral pathway for direct specialist review (protected one-stop slots in rheumatology or ophthalmology), including the use of a dedicated score for assessing the risk for GCA (GCAPS) and vascular ultrasonography in specialist clinics. Our aims for this quality improvement project were to: 1) Audit referral times for suspected GCA patients 2) Optimise the percentage of suspected GCA cases receiving a confirmatory test, notably ultrasound or temporary artery biopsy. Methods We audited the new GCA referrals from January 2022 to June 2023, and compared to the 2018 data. Data were retrospectively collected from electronic health records. Results 44 patients were included (women=29, mean age=68). In 2023, 89% of patients were seen within three days, compared to 47% previously. In 2023, patients were reviewed within a median of two days by a specialist compared to 19 in 2018. Finally, 100% of our patients received a diagnostic test, compared to 79% previously (table 1). A total of 34% of new referrals were diagnosed as GCA. 40 patients had an ultrasound which was positive in 27%, equivocal in 25% and negative in 48%. For the remaining four patients, GCA was excluded without imaging tests/biopsy. 17 patients had biopsy, with 24% being positive for GCA. 52% of referred cases had high GCAPs score and 32% normal inflammatory markers. Conclusion Our fast-track referral pathway facilitated an earlier review for our patients. These results indicate the enhanced safety afforded for suspected GCA patients via a dedicated Fast Track GCA assessment clinic with access to ultrasonography. This also led to a significant reduction in the number of temporal artery biopsies required. Disclosure D. Ioannidis: None. S. Premraj: None. E. Ntatsaki: None.

Giant Cell Arteritis.

Giant cell arteritis (GCA) is the most common primary vasculitis and is associated with potential bilateral blindness. Neither clinical nor laboratory evidence is simple and unequivocal for this disease, which usually requires rapid and reliable diagnosis and therapy. The ophthalmologist should consider GCA with the following ocular symptoms: visual loss or visual field defects, transient visual disturbances (amaurosis fugax), diplopia, eye pain, or new onset head or jaw claudication. An immediate ophthalmological examination with slit lamp, ophthalmoscopy, and visual field, as well as color duplex ultrasound of the temporal artery should be performed. If there is sufficient clinical suspicion of GCA, corticosteroid therapy should be initiated immediately, with prompt referral to a rheumatologist/internist and, if necessary, temporal artery biopsy should be arranged. Numerous developments in modern imaging with colour duplex ultrasonography, MRI, and PET-CT have the potential to compete with the classical, well-established biopsy of a temporal artery. Early determination of ESR and CRP may support RZA diagnosis. Therapeutically, steroid-sparing immunosuppression with IL-6 blockade or methotrexate can be considered. These developments have led to a revision of both the classification criteria and the diagnostic and therapeutic recommendations of the American College of Rheumatologists and the European League against Rheumatism, which are summarised here for ophthalmology.

Analysis of Temporal Artery Biopsy by Provider Across a Large Multi-State Health Care Network.

Temporal artery biopsy (TAB) is the standard test for diagnosing giant cell arteritis. Our objective was to determine which specialists perform TABs and if there is variation across the United States. We performed a cross-sectional analysis in a multi-state health care system, evaluating differences between observed counts of surgical specialty by region, positive diagnoses by region, and positive diagnoses by specialty. Temporal arterial biopsy was performed on 3825 patients with the proportion of specialties performing TAB differing between regions. Temporal artery biopsy was performed by a significantly higher percentage of general surgeons in the Midwest (53.6%) and less vascular surgeons in the West (30.4%). The percentage of positive diagnoses was higher for vascular surgeons (32.7%). We concluded that TAB is performed by physicians of many specialties with the specialty performing most of these procedures varying by region. There is also a difference in the rate of positive diagnoses that varies with surgical specialty.