Diagnosis Of Large Vessel Vasculitis Research Articles

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.

P191 Giant cell arteritis relapses occur in a different arterial territory as compared to diagnosis

Abstract Background/Aims Ultrasonography (US) for diagnosis of large vessel vasculitis (LVV) is a recommended first line diagnostic procedure. We have been running an US led diagnostic pathway in our centre since January 2017. This pathway is also used to diagnose relapsing disease. We present US defined anatomical distribution of relapses in consecutive patients. Methods Patients in whom new and relapsing disease was diagnosed using US were included. Protocolised US examination of the common carotid system (segments of common carotid, external carotid and branches) and those of the subclavian system (segments from origin of subclavian to end of axillary artery and branches) were carried out at diagnosis and relapse. Halo sign in at least two different arteries was needed for establishing new or relapsing disease. Disease characterisation was classified as being in the carotid system, subclavian system, or both. The nature of the disease at relapse was compared to that at diagnosis. Results 279 patients were diagnosed with LVV using US since Jan 2017. 57 (20%) were diagnosed as having a relapse using US. 43/57 (75%) and 28/57 (49%) had involvement of the carotid system at baseline and relapse respectively. 22/57 (39%) and 44/57 (77%) had involvement of the subclavian system at baseline and relapse respectively. A comparison of the disease involvement is as in Figure 1. Conclusion The branches of the common carotid artery (external carotid artery) are commonly involved at diagnosis, but relapse occurs more frequently in the subclavian artery branches. This is especially true when disease affects the carotid system at baseline. The presentation of patients with subclavian system disease is often with only constitutional symptoms and with shoulder girdle pain and stiffness. This may be mistaken for being a polymyalgia rheumatica relapse. It is essential to examine the subclavian system of arteries in patients with LVV before diagnosing polymyalgia rheumatic relapse. Disclosure S. Alanoor: None. G. Ducker: None. C.B. Mukhtyar: None.

Diagnosis of Large Vessel Vasculitis in the community: A Specific Benefit from a Non-Specific Symptom Pathway.

Diagnosis of Large Vessel Vasculitis in the community: A Specific Benefit from a Non-Specific Symptom Pathway.

Hybrid PET/MRI of large vessel vasculitis : Radiation dose compared to PET/CT with view on cumulative effective dose.

The diagnosis of large vessel vasculitis (LVV) is often challenging due to the various clinical appearances and the low prevalence. Hybrid imaging by positron emission tomography and computed tomography (PET/CT) is ahighly relevant imaging modality for diagnostics and disease surveillance but may be associated with asignificant amount of radiation dose especially in patients with complications. The aim of this retrospective analysis was to compare the image quality and impact of hybrid imaging methods PET/CT and PET/MRI on the potential for dose reduction. This retrospective single-center study included acohort of 32patients who were referred to PET/MRI for the evaluation of LVV, including graft infections and fever of unknown origin. This cohort was compared to asimilar cohort of 37patients who were examined with PET/CT in the same period. Mean radiation dose as well as image quality to establish adiagnosis were compared between the groups. The mean radiation dose applied in PET/MRI was significantly lower when compared to PET/CT (mean 6.6 mSV vs. 31.7 mSV; p < 0.001). This effect was based on the partially multiphasic CT protocols. At the same time, diagnostic image quality using a4-point scale showed similar results for both imaging modalities in the work-up of LVV. With PET/MRI, the radiation exposure can be significantly reduced with similar image quality and diagnostic impact. Patients with LVV have ahigher risk of receiving aclinically relevant cumulative effective dose (CED) and PET/MRI should be made available to them.

Molecular imaging of large vessel vasculitis

Large vessel vasculitis (LVV) affects mainly large arteries with giant cell arteritis (GCA) and Takayasu arteritis (TAK) being the two most frequent forms. Clinical symptoms can be non-specific, including headache, fatigue, weight loss, and change in vision. Untreated, LVV may also lead to serious complications such as blindness, aortic aneurysm and dissection. Therefore, rapid recognition of the disease leading to accurate diagnosis and appropriate treatment is essential. FDG-PET/CT imaging has emerged as a sensitive marker of active vascular inflammation and its use in the management of LVV is now integrated in guidelines. In this article, we will discuss the role of FDG-PET/CT for the diagnosis of LVV and monitoring of therapy, as well as review technical and interpretation parameters.

The Role of PET in the Diagnosis and Disease Activity Assessment in Large Vessel Vasculitis

The role of 18F-fluorodeoxyglucose (FDG) positron emission tomography (18F-FDG PET) in the diagnosis of large vessel vasculitis (LVV) is well established. It permits us to assess the extent and the grade of vascular involvement and to rule out the other causes in clinical scenarios characterized by less specific symptoms. The advantages of 18F-FDG PET are far less clear in monitoring disease activity over time. Studies looking for the role of 18F-FDG PET as a potential biomarker had conflicting results and whether and when to repeat it during follow-up is based on clinical experience. A comprehensive assessment, including clinical, laboratory and morphological imaging is still required to monitor patients with large-vessel vasculitis over time. The aim of this review is to present more recent data about the utility of 18 F-FDG PET in the diagnosis and follow-up of LVV.

OA35 Early identification of large vessel vasculitis: a specific benefit of a non-specific symptom pathway?

Abstract Background/Aims Since December 2020 in Cornwall there has been a Non-Specific Symptom Pathway (NSSP): a 2-week-wait pathway by which GPs can access a CT thorax, abdomen &amp; pelvis (CT-TAP) to assess non-specific symptoms where there is a suspicion of malignancy, but conventional 2-week-wait referral criteria are not met. An unexpected consequence of this pathway was the finding of cases of suspected large vessel vasculitis (LVV) being referred to rheumatology outpatients. Methods Cases with a new diagnosis of LVV or cancer were identified using the NSSP database over the period of December 2021- May 2022. Clinical and laboratory features were analysed and compared. During this time period a Logiq E10 US machine was acquired by the department, enabling axillary US to be performed for some of the suspected LVV cases that were referred to rheumatology. Results Of the 241 accepted referrals, 14 patients (5.81%) had a subsequent definite cancer diagnosis, 6 (2.49%) had LVV diagnosed as a direct consequence of the NSSP. 5 (83%) cases of LVV had CRP &amp;gt;60 versus 4 (33%) of the cancer patients where measured. Mean CRP was 38.9 in cancer patients and 82.3 in LVV (normal 0-5mg/L). Mean platelet count was 401 in cancer patients, 510 in LVV patients (normal 150-400x109). 3 LVV patients had immunoglobulins and serum protein electrophoresis tested, of which 2 had significantly raised IgG and 1 was confirmed as polyclonal. In one case, significant thoracic aneurysmal dilatation was identified; a 59-year-old previously healthy woman presented to primary care with fatigue, night sweats and arm pain. Investigations showed anaemia, thrombocytosis, polyclonal high immunoglobulins, CRP 74. CT-TAP via NSSP revealed thoracic aorta wall thickening with aneurysmal dilatation, diameter being 4.5cm at the aortic arch. Subsequently the patient was referred to vascular surgeons and rheumatology. Rheumatology clinic review noted no symptoms of cranial giant cell arteritis or polymyalgia rheumatica. Examination revealed significant blood pressure discrepancy between right and left arms (diastolic difference of 62mmHg) and bilateral axillary bruits. Bilateral axillary artery ultrasound revealed significant intima-media thickening: right distal 1.19mm, left distal 1.37mm (normal less than 0.9mm) consistent with LVV. 10mg Prednisolone and subsequently leflunomide 10mg were initiated with resolution of inflammatory markers and symptoms. Surgical intervention was not felt to be required but regular surveillance continues. Conclusion Polyclonal raised IgG, unexplained raised CRP and thrombocytosis, arm blood pressure discrepancy and axillary bruits may be useful indicator tests for referral to the NSSP. LVV diagnosis normally requires extensive inpatient investigations in patients with pyrexia-of-unknown-origin and can be challenging in the absence of PMR or cranial GCA symptoms. As well as early identification of cancer, NSSP has the additional benefit of detecting cases of LVV that may have otherwise gone unnoticed, including the cases with secondary aneurysmal change. Disclosure R. Machin: None. M. Hughes: None.

E093 The effect of new classification criteria on the diagnosis of large vessel vasculitis

Abstract Background/Aims Giant cell arteritis and Takayasu arteritis are the two recognised forms of large vessel vasculitis. Clinically there is recognition of large vessel vasculitides which are not easily classified into the two forms. Classification criteria have been proposed since 1990 and have been updated in 2022. Classification criteria should be able to minimise the number of cases that are unclassifiable, and the number of cases that are classified into more than one set. We test both sets of criteria to test their performance in our cohort. Methods In our centre, between January 2011 to December 2020, 270 individuals were diagnosed as having large vessel vasculitis by virtue of having either a positive biopsy, ultrasonography, or positron emission tomography. The 1990 and the 2022 classification criteria were applied to our cohort. Results The mean age was 74. 181 were female. The results are as in Table 1. Using the 1990 criteria, 2 individuals met both classifications and 30 did not meet either. Using the 2022 criteria, 3 individuals met both classifications and 24 did not meet either. The numbers classified as having Takayasu arteritis has reduced from 13/270 to 2/270. The numbers classified as giant cell arteritis have increased from 225/270 to 241/270. Conclusion The new classification criteria have expanded the phenotype recognised as giant cell arteritis by mainly including previously unclassified individuals, and narrowed the phenotype recognised as Takayasu mostly by declassifying it as not meeting any criteria. Overall, the new criteria improve classification for 5/270 (1.8%) cases. Disclosure C.B. Mukhtyar: None. C. Beadsmoore: None. F. Coath: None. G. Ducker: None. K. Sisson: None. R.A. Watts: None.

18F]FDG PET/CT in Large Vessel Vasculitis: The Impact of Expertise and Confounders on Image Analysis.

Diagnosis of vasculitis is challenging. To avoid invasive approaches, clinical guidelines recommend the use of diagnostic imaging. This study aimed at evaluating the diagnostic accuracy of [18F]-fluorodeoxyglucose ([18F]FDG) position emission tomography/computed tomography (PET/CT) in large vessel vasculitis (LVV) and how this is affected by inter-operator variability. A total of 279 patients who performed [18F]-FDG PET/CT for suspicion of LVV were retrospectively analyzed. We tested the qualitative and semi-quantitative analysis and parameters influencing image quality and interpretation. Exams were evaluated by two readers with different experience and their performance was compared. LVV diagnosis was confirmed in 81 patients. [18F]-FDG PET/CT accuracy was 73% and 67% for the expert reader and less experienced reader, respectively. The expert reader overall performed better than the less experienced one, with higher accuracy in patients with normal BMI (77.3 vs. 63.8%), normal level of glycemia (73.3 vs. 65%), younger age (76.6 vs. 68.2%), and when no therapy was in course at time of imaging (76.7 vs. 66.7%). The diagnostic performance of both readers did not improve using semi-quantitative parameters. We confirmed the appropriateness of the recommended criteria for image acquisition and interpretation, underlining the importance of experience in image interpretation for the optimal diagnostic performance of [18F]FDG PET/CT in vasculitis.

The role of ultrasound and FDG-PET/CT to detect extracranial artery involvement in patients with suspected large vessel vasculitis.

To assess the accuracy of ultrasound (US) versus fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) to identify extracranial involvement in large vessel vasculitis (LVV). A retrospective observational study of patients with suspected LVV. All patients underwent US exam within 24 h per protocol. FDG-PET/CT was performed according to clinician criteria. The gold standard for LVV diagnosis was clinical confirmation after 6 months. Of the 113 patients included (74.3% female, mean age 74 years), 37 (32.7%) were diagnosed with LVV after 6 months. The sensitivity and specificity of US were 86.5% and 96.1%, respectively. Only 12 (42.9%) of 28 patients undergoing a FDG-PET/CT per clinician criteria showed positive findings. The sensitivity and specificity of FDG-PET/CT for LVV were 61.1% and 90%, respectively. Taking FDG-PET/CT as the reference, US showed extracranial inflammation in 10/12 (83.3%) and detected 2 (12.5%) additional cases of extracranial involvement with negative FDG-PET/CT. Conversely, FDG-PET/CT was positive in two patients with negative US (one isolated aortitis and one aortoiliac involvement). US and FDG-PET/CT are both valid tools to detect extracranial involvement. The presence of US extracranial artery inflammation is consistent with FDG-PET/CT examination, although a negative US scan does not rule out extracranial involvement.

VASCULITIS AND RENOVASCULAR HYPERTENSION – A CASE REPORT

Objective: Vasculitides are a group of rare, systemic diseases that induce inflammatory reactions in blood vessels, causing a reduction of blood flow and ischemia. In the kidney, luminal narrowing reduces blood flow and activates the renin-angiotensin-aldosterone system, causing renovascular hypertension. Design and method: Clinical case report. Results: A 47-year-old male with previous intestinal tuberculosis and hypertension diagnosed two years prior (blood pressure around 220/110 mmHg) was referred to our Hypertension Clinic. He reported self-limited episodes of lumbar pain, tender erythematous nodules in the shins and arthralgias. His mean office blood pressure was 203/118 mmHg, confirmed in home blood pressure monitoring, without medication. He had left ventricular concentric hypertrophy and chronic kidney disease (eGFR 66 mL/min/1.73m2) with albuminuria (561 mg/24 h). Verapamil and clonidine were prescribed to search for secondary hypertension but he missed the following appointment. A few months later he was admitted to the Intensive Care Unit due to a hypertensive emergency, with acute kidney failure and a large peri-renal hematoma. A CT scan and an angiography showed bilateral renal scarring, intrarenal pseudoaneurysms and small irregularities in the renal arteries. The immunologic panel was negative. A PET scan showed a slight enhancement of the aorta walls and common carotid arteries and the diagnosis of large-vessel vasculitis was established. He was discharged with high-dose corticosteroids and lisinopril and returned to our Hypertension Clinic. His blood pressure remained uncontrolled despite full-dose amlodipine, chlorthalidone and nebivolol; lisinopril was stopped due to worsening kidney function. Due to doubts on the diagnosis, the CT scan was repeated, now showing also irregularities in the common hepatic artery and mesenteric artery, suggesting a medium-vessel vasculitis, namely polyarteritis nodosa, and cyclophosphamide was started. His blood pressure is now controlled with lisinopril 2.5 mg, amlodipine 10 mg bid, furosemide 40 mg bid, nebivolol 5 mg and clonidine 0,15 mg tid and his kidney function is stable. Conclusions: Renovascular hypertension is responsible for less than 1% of all cases of hypertension and, when present, it is usually caused by atherosclerotic disease or fibromuscular dysplasia. However, in more infrequent cases, an inflammatory systemic disease may be present and must be considered.

P297 Takayasu arteritis presents at an older age in a northern European population

Abstract Background/Aims The definition of Takayasu arteritis includes the age of onset of disease as being &amp;lt;50 years. It has been reported most frequently in young females from Asian populations. We investigated whether the epidemiological features are the same in Norfolk, where the population is predominantly of northern European ancestry. Methods n our centre, cases are classified using validated international criteria. The electronic records of our vasculitis clinic were reviewed to identify all individuals with a new diagnosis of large vessel vasculitis from 2011-2020 who met a modified ACR 1990 criteria for Takayasu arteritis. The original criteria include decreased brachial artery pulse, bruit over subclavian arteries or aorta, and arteriogram abnormality. The respective modifications of these three criteria were to accept decreased radial pulse as well as the brachial pulse, bruit over the axillary artery as well as the subclavian artery, and abnormality of positron emission tomography and/or ultrasonography instead of arteriograms. Results 14 individuals met the modified ACR 1990 criteria for Takayasu arteritis. 13 were female. The mean (standard deviation) age at diagnosis was 68.2 (7.7) years. None of the individuals were &amp;lt;40 years old. On presentation, 8 had upper limb claudication, 8 had pulse discrepancy, 4 had a blood pressure difference &amp;gt;10 mm Hg systolic, and 8 had an audible bruit over either subclavian or axillary artery. The diagnosis was confirmed on positron emission tomography in 7, ultrasonography of extracranial arteries in 5, and 2 by both modalities. The mean (standard deviation) ESR was 66.7 (48.1) and CRP was 49.2 (33.8). 2/14 also met the ACR 1990 criteria for GCA. Conclusion Takayasu arteritis can present at an older age in Norfolk where the population predominantly has northern European ancestry. Some of these individuals also fulfil the criteria for GCA. This has implications for treatment, identification of immunogenetic factors and disease classification. Disclosure T. Ecclestone: None. F. Coath: None. G. Ducker: None. S. Fordham: None. C. Mukhtyar: None.

The Italian Society of Rheumatology clinical practice guidelines for the management of large vessel vasculitis.

Since of the last publication of last recommendations on primary large-vessel vasculitis (LVV) endorsed by the Italian Society of Rheumatology (SIR) in 2012, new evidence emerged regarding the diagnosis and the treatment with conventional and biologic immunosuppressive drugs. The associated potential change of clinical care supported the need to update the original recommendations. Using the grading of recommendations assessment, development and evaluation (GRADE)-ADOLOPMENT framework, a systematic literature review was performed to update the evidence supporting the European Alliance of Associations for Rheumatology (EULAR) guidelines on LVV as reference. A multidisciplinary panel of 12 expert clinicians, a trained nurse, and a patients' representative discussed the recommendation in cooperation with an Evidence Review Team. Sixty-one stakeholders were consulted to externally review and rate the recommendations. Twelve recommendations were formulated. A suspected diagnosis of LVV should be confirmed by imaging or histology. In active GCA or TAK, the prompt commencement of high dose of oral glucocorticoids (40-60 mg prednisone-equivalent per day) is strongly recommended to induce clinical remission. In selected patients with GCA (e.g., refractory or relapsing disease or patients at risk of glucocorticoid related adverse effects) the use of an adjunctive therapy (tocilizumab or methotrexate) is recommended. In all patients diagnosed with TAK, adjunctive therapies, such as conventional synthetic or biological immunosuppressants, should be given in combination with glucocorticoids. The new set of SIR recommendations was formulated in order to provide a guidance on both diagnosis and treatment of patients suspected of or with a definite diagnosis of LVV.

Semi-Quantitative and Quantitative [18F]FDG-PET/CT Indices for Diagnosing Large Vessel Vasculitis: A Critical Review.

To confirm the diagnosis of large vessel vasculitis (LVV) with high accuracy, one of the recommended imaging techniques is [18F]Fluoro-2-deoxy-d-glucose positron emission tomography with computed tomography ([18F]FDG-PET/CT). Visual assessment of [18F]FDG uptake in the arterial wall compared to liver uptake is the mainstay for diagnosing LVV in routine clinical practice. To date, there is no consensus on the preferred semi-quantitative or quantitative parameter for diagnosing LVV. The aim of this review is to critically update the knowledge on the available evidence of semi-quantitative and quantitative [18F]FDG uptake parameters for diagnosing LVV and to provide future directions for methodological standardization and research.

Multimodality Imaging of Large-Vessel Vasculitis, From the AJR Special Series on Inflammation.

Large-vessel vasculitis (LVV) is a noninfectious inflammation of the large vessels, including the aorta and its main branches. Imaging plays an essential role in diagnosing LVV given the challenges of tissue biopsy. This article reviews the types of LVV and the multimodality imaging tools available to establish its diagnosis. The cornerstone of imaging diagnosis is morphologic assessment using gray-scale ultrasound (US), gray-scale US combined with color Doppler US, CTA, or MRA. In the last decade, substantial progress has been made in functional and molecular imaging with FDG PET/CT for the diagnosis of LVV. Investigation is ongoing to develop novel MRA techniques and new PET tracers to assess disease activity and to differentiate the various vasculitides. An algorithm is provided to guide imaging technique selection based on the patient's specific clinical presentation.

Vessel Wall Inflammatory Activity as Determined by F-18 Fluorodeoxyglucose PET in Large Vessel Vasculitis Is Attenuated by Immunomodulatory Drugs.

F-18 fluorodeoxyglucose (F-18 FDG) PET/CT plays an increasing role in the diagnostic workup of large vessel vasculitis (LVV); however, information on the relationship between immunosuppressive drugs and vessel wall uptake is limited. In 94 patients with a confirmed diagnosis of LVV, the vessel wall-to-liver ratio (VLR) was assessed in eight vessel segments. Patients were grouped according to intake of immunomodulatory drugs (Group 1, prednisone; Group 2, prednisone + methotrexate; and Group 3, prednisone + others) and compared to treatment-naïve individuals. A total of 54/94 (57.4%) were treated with immunomodulatory drugs (Group 1, 29/49 (53.7%); Group 2, 9/54 (16.7%); Group 3, 11/54 (20.4%); and Group 4, 5/54 (9.3%)), whereas the remainder received no therapy (40/94 (42.6%)). The mean VLR of the arterial segments correlated significantly with the hematopoietic organs (r ≥ 0.22, p ≤ 0.05), c-reactive protein (r ≥ 0.25, p ≤ 0.05), and prednisone dosage (r ≥ −0.4, p ≤ 0.05). Relative to treatment-naïve patients, a significantly lower VLR was recorded in 5/8 (62.5%) of the investigated vessel segments in Group 1 (p ≤ 0.02), in 6/8 of the vessel segments in Group 2 (75.0%, p ≤ 0.006), and in 7/8 of the segments in Group 3 (87.5%, p ≤ 0.05). In LVV, the F-18 FDG uptake in vessel wall as a marker of inflammatory activity was attenuated by immunomodulatory drugs, which provides a foundation for future serial monitoring of treatment efficacy.

A Review on the Value of Imaging in Differentiating between Large Vessel Vasculitis and Atherosclerosis

Imaging is becoming increasingly important for the diagnosis of large vessel vasculitis (LVV). Atherosclerosis may be difficult to distinguish from LVV on imaging as both are inflammatory conditions of the arterial wall. Differentiating atherosclerosis from LVV is important to enable optimal diagnosis, risk assessment, and tailored treatment at a patient level. This paper reviews the current evidence of ultrasound (US), 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography (FDG-PET), computed tomography (CT), and magnetic resonance imaging (MRI) to distinguish LVV from atherosclerosis. In this review, we identified a total of eight studies comparing LVV patients to atherosclerosis patients using imaging—four US studies, two FDG-PET studies, and two CT studies. The included studies mostly applied different methodologies and outcome parameters to investigate vessel wall inflammation. This review reports the currently available evidence and provides recommendations on further methodological standardization methods and future directions for research.

The utility of PET/CT in large vessel vasculitis

18F-FDG PET/CT occupies a growing role in the diagnosis of large vessel vasculitis (LVV), illustrating enhanced uptake in the lining of large vessels. A retrospective single center study was conducted of patients who underwent 18F-FDG PET/CT scans between 2009 and 2019 at Sheba Medical Center, Israel. The imaging results were analyzed for evidence of LVV. We reviewed the PET/CT scans of 126 patients and identified 57 studies that either showed evidence of active LVV or that had been performed in patients previously treated for systemic vasculitis. In 6 patients with fevers of unknown origin and elevated inflammatory markers, PET/CT revealed LVV. Six of 13 patients previously treated for systemic vasculitis demonstrated persistent large vessel uptake. LVV was identified in 8 patients with other autoimmune diseases, and in 4 diagnosed with infectious aortitis. In 26 patients who underwent malignancy surveillance, PET/CT revealed more localized large vessel wall inflammation. Our results illustrate that PET/CT may identify large vessel wall inflammation in patients with a suspicion of LVV, and incidentally in patients who undergo malignancy surveillance. PET/CT may also help delineate the presence and extent of vessel inflammation in patients with LVV and in those with other autoimmune diseases.

Use of Ultrasound in the Diagnosis and Management of the Vasculitides.

The aim of this review paper is to evaluate the current data regarding clinical use of ultrasound (US) for diagnosis of systemic vasculitis. In recent years, US has emerged as an image modality taking a central role in the diagnosis and monitoring of vasculitides by measuring vessel wall inflammation and changes in vessel wall thickness. US has been recognized as an important tool predominantly in the diagnosis of large vessel vasculitis (LVV). Signs like the "halo sign" in temporal arteries of patients with giant cell arteritis (GCA) have demonstrated to be a robust marker. In other types of vasculitides the role of US is not well defined yet but could be of help by diagnosing secondary findings when there is organ involvement, like interstitial lung disease in small vessel vasculitis (SVV). Different modes of ultrasound (US) are being studied for this purpose, especially since it is a non-invasive technique that can limit exposure to ionizing radiation. In conclusion there is clear evidence for the use of US particularly color duplex US (CDS) in the diagnosis of LVV like GCA and Takayasu's arteritis (TAK). Nevertheless, there is urgent need for more data in regard to the use of US in small/medium vessel vasculitis, as well as the role of US in monitoring of patients with LVV.

Elevated alkaline phosphatase: The initial laboratory abnormality in an atypical presentation of Takayasu Arteritis

Background: Takayasu Arteritis rarely presents in men over the age of 40, particularly with an isolated elevated alkaline phosphatase level. Case presentation: A 46-year-old Hispanic man with no prior history of rheumatic disease presented with acute onset of chest pain radiating to his left upper extremity. His cardiovascular workup was unremarkable with exception of an elevated alkaline phosphatase level (ALP), approximately three times the upper limit of normal. Over a short period of time, his ALP up trended and clinical exam revealed BP discrepancies between his upper extremities, vascular bruits and a profound asymmetry in brachial and radial pulses. MRA-Chest confirmed mural thickening and luminal narrowing of the proximal left subclavian artery and the diagnosis of Takayasu Arteritis was made. Upon receiving glucocorticoids and corticosteroid sparing immunosuppressive agents, his clinical manifestations (chest pain, left arm claudication) had markedly improved while ALP decreased. Conclusion: In addition to clinical exam and imaging studies, laboratory studies (such as ALP) may aid in support of a diagnosis of large vessel vasculitis. In the literature, this has been described primarily in those with giant cell arteritis/polymyalgia rheumatica. In patients with an elevated ALP in the appropriate clinical setting, consideration should be given to the diagnosis of Takayasu Arteritis. This may aid in early initiation of appropriate therapy.