EULAR recommendations for the use of imaging in large vessel vasculitis in clinical practice: 2023 update

FDG PET/CT in large vessel vasculitis

Large vessel vasculitides (LVV) such as giant cell arteritis, Takayasu arteritis and aortitis/periaortitis are characterised by immune-mediated inflammation of medium to large arteries. Clinical disease manifestations can be non-specific and diagnostic imaging plays an important role in the diagnostic pathway. In recent years, FDG PET/CT has proven to be a powerful metabolic tool that can provide a wholed body, non-invasive assessment of vascular inflammation. This review outlines the clinical features of large vessel vasculitis and the closely related entity of polymyalgia rheumatica, summarises the evidence for FDG PET/CT in the assessment of these conditions, and provides guidance for patient preparation, image acquisition and interpretation.

Recommendations for defining giant cell arteritis fast-track clinics. English version

A German expert committee recommends defining fast-track clinics (FTC) for the acute diagnosis of giant cell arteritis (GCA) as follows: easy and prompt reachability at least on weekdays, scheduling appointments ideally within 24 h, examination by a specialist with GCA expertise, ≥ 2 experts per FTC, ≥ 50 patients with suspected GCA per year, sonologists with ≥ 300 (≥ 50) temporal and axillary artery examinations, adherence to standard operating procedures, availability of an ≥ 18 (≥ 15) MHz and a lower frequency linear ultrasound probe, and collaboration with partners for neurology and ophthalmology consultations, magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT, possibly CT), and for temporal artery biopsy.

Diagnostic performance of a newly launched Canadian fast-track ultrasound clinic by rheumatologists for the diagnosis of giant cell arteritis

BACKGROUND

Giant cell arteritis (GCA) can present diagnostic challenges and early diagnosis is crucial due to potential ischemic complications. Recent guidelines suggest that a suspected diagnosis should be confirmed with temporal artery biopsy or imaging, including ultrasound (US). In our Canadian setting, point-of-care temporal artery US was near unavailable, and biopsy remains the standard of care. We hypothesize that launching a fast-track US clinic by rheumatologists may spare the need for a temporal artery biopsy. Therefore, this study aimed to assess the diagnostic performance of US in this newly launched fast-track clinic.

METHODS

In this single-center retrospective cross-sectional analysis, 99 visits were identified from the fast-track clinic between January 2020 and July 2022. Each subject had an US according to a standard protocol for suspicion of either new-onset or relapse of GCA. Ultrasonographers were rheumatologists who acquired training on vascular US techniques before launching the clinic. For each patient presenting with suspected new-onset GCA, the pretest probability was calculated using the Southend GCA probability score. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using the rheumatologist clinical diagnosis as the gold standard for GCA diagnosis.

RESULTS

A total of 22 subjects had a diagnostic of GCA and 77 had another diagnostic. Patients with and without GCA were, respectively, 81.8% versus 72.7% females, had a mean age of 76.6 ± 7.7 versus. 74.8 ± 9.8 years, and a mean CRP of 73.4 ± 57.8 versus 38.3 ± 59.9 mg/l. Temporal artery US demonstrated a sensitivity of 86.3% [95% confidence interval (CI), 65.1-97.1%], a specificity of 90.9% (95% CI, 82.2-6.3%), a PPV of 73.1% (95% CI, 56.8-84.9%), and a NPV of 95.9% (95% CI, 89.0-.5%). 14 patients had a suspicion of relapse and were all correctly identified by the US. Among those with suspicion of new-onset 27, 34 and 24 US were performed for high, intermediate, and low pretest probability of GCA, respectively. The high-risk subgroup demonstrated higher PPV while similar sensitivity/specificity was observed between all three subgroups.

CONCLUSION

Our results highlight the benefits of US as a key diagnostic tool for GCA, particularly when combined with clinical evaluations. An excellent discriminative ability for diagnosis of GCA was shown in this newly launched clinic suggesting that the role of TAB may need to be redefined. These findings will guide on broader implementation of US programs for GCA.

Brain computed tomography perfusion alterations in patients with Takayasu arteritis with steno-occlusive carotid arteries: a retrospective study

INTRODUCTION/OBJECTIVE

Data on computed tomography perfusion (CTP) in Takayasu arteritis (TAK) patients are limited. Herein, we used CTP combined with computed tomography angiography (CTA) to investigate the brain hemodynamic status in TAK patients with stenosis/occlusive carotid arteries.

METHODS

We retrospectively analyzed 49 TAK patients with carotid artery stenosis or occlusion who had ischemic manifestations and completed a one-stop aortic CTA and brain CTP at Xijing Hospital between 2021 and 2023. Hemodynamic parameters, including cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time to maximum (Tmax), were compared between groups using independent samples t-test or the Mann-Whitney U test. Relationships among CTP parameters and disease activity were evaluated by correlation analyses.

RESULTS

Among 49 patients (43 females; age 38.7 ± 11.1 years), 15 had common carotid artery occlusion (four bilateral, six right, and five left). Compared with the non-occlusion group, the occlusion group had longer MTT and Tmax (p < 0.05) but showed no differences in CBV and CBF values. Patients with different degrees of lesions on two sides of the carotid artery (n = 31) had lower mean CBF on the severely affected side than on the contralateral side (p = 0.022). In contrast, mean MTT (p = 0.036) and Tmax (p = 0.024) were longer. Patients with more severe ischemic symptoms had longer Tmax than patients with mild symptoms (p < 0.05). Tmax was moderately correlated with disease activity indices (p < 0.05).

CONCLUSIONS

Alterations in cerebral hemodynamic perfusion were observed in TAK patients. The implications of these findings in evaluating brain ischemia and dysfunction require further investigation. Key Points • Alterations in cerebral hemodynamic perfusion were observed in TAK patients. • Compared with patients without common carotid artery occlusion, patients with occlusion had longer MTT and Tmax values. • In patients with different degrees of lesions on the two sides of the carotid artery, the severely affected side had a lower CBF and prolonged MTT and Tmax than the contralateral side. • Patients with moderate-to-severe ischemic manifestations had a longer Tmax than patients with mild symptoms, and MTT and Tmax correlated with disease activity indices.

Current and Emerging Approaches to Imaging Large Vessel Vasculitis

Large vessel vasculitides (LVV) comprise a group of inflammatory disorders that involve the large arteries, such as the aorta and its primary branches. The cause of LVV is often rheumatologic and includes giant cell arteritis and Takayasu arteritis. Giant cell arteritis is the most common form of LVV affecting people >50 years of age with a slight female predominance. Takayasu arteritis is more frequently seen in younger populations and is significantly more common in women. Prompt identification of LVV is crucial as it can lead to debilitating complications if left untreated, including blindness in the case of giant cell arteritis and large artery stenosis and aneurysms in the case of all forms of LVV. Noninvasive imaging methods have greatly changed the approach to managing LVV. Today, imaging (with ultrasound, magnetic resonance imaging, computed tomography, and positron emission tomography) is routinely used in the diagnosis of LVV. In patients with giant cell arteritis, imaging often spares the use of invasive procedures such as temporal artery biopsy. In addition, vascular imaging is also crucial for longitudinal surveillance of arterial damage. Finally, imaging is currently being studied for its role in assessing treatment response and ongoing disease activity and its potential value in determining the presence of vascular wall remodeling (eg, scarring). This review explores the current uses of noninvasive vascular imaging in LVV.

Imaging Challenges and Developments in Large-vessel Vasculitis

Vascular imaging is an integral part of large-vessel vasculitis (LVV) evaluation and management. Several imaging modalities are currently employed in clinical practice including vascular ultrasound, computed tomography angiography, MRI and magnetic resonance angiography, and 18F-fluorodeoxyglucose PET. Well-established roles for imaging in LVV include disease diagnosis and assessment of luminal lesions reflecting vascular damage. The ability of imaging to determine treatment response, monitor disease activity, and predict future arterial damage is an area of active research.

Giant-cell arteritis on photon-counting detector CT: A case report

A 77-year-old woman presented to our hospital with a 2-week history of fever, headache, and induration along the bilateral superficial temporal arteries (STAs). The color Doppler ultrasonography of the STA showed a hypoechoic mural thickening surrounding a residual color flow. A contrast-enhanced photon-counting detector (PCD) CT demonstrated mural thickening and stenosis of the bilateral STAs. The patient underwent a biopsy of the right STA. Histopathological findings were consistent with giant cell arteritis (GCA). The patient's symptoms were temporarily relieved after initiation of steroid treatment, but jaw claudication occurred 2 months later. Contrast-enhanced CT showed improved vascular abnormalities of the STAs but new mural thickening and stenosis of the bilateral maxillary artery. Due to its higher resolution, image contrast, and lower noise, PCD-CT may have great potential in detecting, diagnosing, and monitoring GCA.

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

OBJECTIVE

Aortitis 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.

METHODS

Multicentre 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.

RESULTS

196 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.

CONCLUSION

In 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.

[Recommendations for defining giant cell arteritis fast-track clinics]

An expert committee recommends defining fast-track clinics (FTC) for the acute diagnostics of giant cell arteritis (GCA) as follows: low-threshold, easy and prompt reachability at least on weekdays, scheduling appointments ideally within 24 h, examination by a specialist with GCA expertise, ≥ 2 experts per FTC, ≥ 50 patients with suspected GCA per year, sonologists with ≥ 300 (≥ 50) temporal and axillary artery examinations, adherence to standard operating procedures, availability of an ≥ 18 (≥ 15) MHz and a lower frequency linear ultrasound probe and collaboration with partners for fast performance of neurological and ophthalmological examinations, magnetic resonance imaging (MRI), positron emission tomography-computed tomography (PET-CT, possibly CT) and for temporal artery biopsy.

What is new in imaging to assist in the diagnosis of giant cell arteritis and Takayasu's arteritis since the EULAR and ACR/VF recommendations?

Over the past decades, fundamental insights have been gained to establish the pivotal role of imaging in the diagnosis of large-vessel vasculitis, including giant cell arteritis (GCA) and Takayasu's arteritis (TAK). A deeper comprehension of imaging modalities has prompted earlier diagnosis leading to expedited treatment for better prognosis. The European Alliance of Associations in Rheumatology (EULAR) recommended in 2023 that ultrasound should be the initial imaging test in suspected GCA, and Magnetic Resonance Imaging (MRI) remains the first-line imaging modality in suspected TAK. We summarize the recent advances in diagnostic imaging in large vessel vasculitis, highlighting use of combination imaging modalities, and discuss progress in newer imaging techniques such as contrast-enhanced ultrasound, shear wave elastography, ocular ultrasound, ultrasound biomicroscopy, integration of Positron Emission Tomography (PET) with MRI, novel tracer in PET, black blood MRI, orbital MRI, and implementation of artificial intelligence (AI) to existing imaging modalities. Our aim is to offer a perspective on ongoing advancements in imaging for the diagnosis of GCA and TAK, particularly innovative technology, which could potentially boost diagnostic precision.

Imaging in Large Vessel Vasculitis-A Narrative Review

Vasculitis refers to a group of rare conditions characterized by the inflammation of blood vessels, affecting multiple systems. It presents a diagnostic and therapeutic challenge due to its broad clinical manifestations. Vasculitis is classified based on the size of the affected vessels: small, medium, large, or variable-sized. Large vessel vasculitis (LVV), particularly giant cell arteritis (GCA) and Takayasu arteritis (TAK), has garnered attention due to its significant morbidity and mortality. Both conditions involve immune-mediated inflammation of the vascular wall, despite differing in epidemiology and presentation. Early identification is crucial to prevent complications like organ ischemia and hemorrhage. Diagnostic accuracy can be hampered by false negative results, making comprehensive investigation essential. Vascular imaging, including computed tomography angiography (CTA), ultrasound (US), magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT), is key in diagnosing vasculitis, revealing vessel wall thickening and other suggestive features. This article reviews typical and atypical CT and CTA findings in LVV, discusses imaging modalities, and highlights their role in therapeutic management and prognosis. It emphasizes the importance of a multidisciplinary approach and the critical role of radiologists in improving patient outcomes in LVV.

18F-FDG-PET/CT Scan for Detection of Large Vessel Involvement in Giant Cell Arteritis: Arteser Spanish Registry

Background/Objectives: Imaging studies have transformed the diagnosis of large vessel vasculitis (LVV) involvement in giant cell arteritis (GCA). A positron emission tomography/computed tomography (PET/CT) scan with 18-fluorodeoxyglucose (18F-FDG) has emerged as a valuable tool for assessing LVV. We aimed to determine the utility of an 18F-FDG-PET/CT scan in detecting LVV in GCA in the ARTESER registry. Methods: The ARTESER study is a large multicenter, retrospective, longitudinal, and observational study, promoted by the Spanish Society of Rheumatology. It included patients newly diagnosed with GCA across 26 tertiary hospitals from 1 June 2013 to 29 March 2019. Patients with a diagnosis of incidental GCA were included if they fulfilled specific criteria, including the ACR 1990 criteria, positive imaging examinations, or the expert clinical opinion of investigators. Differences between patients with positive and negative 18F-FDG-PET/CT scan results were analyzed using a bivariate model. A regression model assessed associations in patients with a positive scan, and the predictive capacity of the cumulative dose of glucocorticoids (GC) on PET scan outcomes was evaluated using ROC curve analysis. Results: Out of 1675 GCA patients included in the registry, 377 met the inclusion criteria of having an 18F-FDG-PET/CT scan. The majority were diagnosed with a cranial GCA phenotype, and 65% had LVV. The thoracic aorta was the most frequently affected. Cardiovascular disease, diabetes, and older age had a negative association with a positive scan outcome. The OR for having a positive 18F-FDG-PET/CTC scan was lower as the number of days increased. Depending on the cumulative dosage of the GC, the 18F-FDG-PET/CT scan showed an AUC of 0.74, with a Youden index > 60 mg/day. Conclusions: Younger patients showed a higher probability of presenting LVV as detected by the 18F-FDG-PET/CT scan. The timing of the examination and the cumulative dosage of the GC influenced the likelihood of a positive result, with earlier tests being more likely to detect inflammation.

An overview of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in giant cell arteritis

PET/CT is an imaging modality that is increasingly being used to diagnose large-vessel vasculitis. In the case of giant cell arteritis, it was first used to demonstrate inflammation of the walls of large arterial trunks such as the aorta and its main branches, showing that aortic involvement is common in this vasculitis and associated with the occurrence of aortic complications such as aneurysms. More recently, with the advent of digital PET/CT, study of the cranial arteries (i.e., temporal, occipital, maxillary and vertebral arteries) has become possible, further increasing the diagnostic interest of this examination for the diagnosis of GCA. Despite these advantages, there are still limitations and questions regarding the use of PET/CT for the diagnosis and especially the follow-up of GCA. The aim of this review is to take stock of currently available data on the use of PET/CT for GCA diagnosis and follow-up.

Five-Year Data from the Interdisciplinary Giant-Cell Arteritis Registry at the University Hospital of Würzburg: Value of Temporal Artery Biopsy

BACKGROUND

Giant-cell arteritis (GCA) requires immediate diagnosis and therapy. The University Hospital of Würzburg established the Centre for Giant-cell Arteritis (ZeRi) to improve interdisciplinary collaboration.

AIM OF THE STUDY

Retrospective evaluation of five-year data to assess the clinical relevance of several diagnostic methods, including temporal artery biopsy.

PATIENTS AND METHODS

Retrospective evaluation of 101 patients with suspected GCA who had undergone interdisciplinary examination and biopsy between 2017 and 2022. We analysed specificity and sensitivity in clinical symptoms, ESR, CRP, scalp MRI, temporal artery sonography, and temporal artery biopsy.

RESULTS

GCA was diagnosed after completing diagnostic testing in 75 of 101 patients with suspected GCA. By definition, biopsy showed a positive predictive value of 100% and a specificity of 84.6%; however, negative predictive value was 51.2%. Sonography of the temporal artery and MRI showed a positive predictive value of more than 93% and sensitivity of 62.5% and 76.1%, respectively. Clinical symptoms showed the highest sensitivity at 92% with a specificity of 57.7%. ESR and CRP were significantly higher in patients with GCA than in patients without GCA, whereby CRP values showed higher predictive power than did ESR.

CONCLUSIONS

Most GCA cases can be detected with a precise medical history as well as ESR and CRP assessment. Sonography and MRI on the scalp can usually confirm suspected GCA, only requiring temporal artery biopsy in exceptional cases.

EANM/SNMMI guideline/procedure standard for [18F]FDG hybrid PET use in infection and inflammation in adults v2.0

INTRODUCTION

Hybrid [18F]FDG PET imaging is currently the method of choice for a wide variety of infectious and inflammatory disorders and was recently adopted in several clinical guidelines. A large amount of evidence-based articles, guidelines and appropriate use criteria have been published since the first version of this guideline in 2013.

PURPOSE

To provide updated evidence-based information to assist physicians in recommending, performing and interpreting hybrid [18F]FDG PET examinations for infectious and inflammatory disorders in the adult population.

METHODS

A systematic literature search of evidence-based articles using whole-body [18F]FDG hybrid imaging on the indications covered within this guideline was performed. All systematic reviews and meta-analyses published within the last 10 years until January 2023 were identified in PubMed/Medline or Cochrane. For each indication covered in this manuscript, diagnostic performance was provided based on meta-analyses or systematic reviews. If not available, results from prospective or retrospective studies were considered based on predefined selection criteria. RESULTS AND CONCLUSIONS: Hybrid [18F]FDG PET is extremely useful in the work-up and management of adults with infectious and inflammatory diseases, as supported by extensive and rapidly growing evidence-based literature and adoption in clinical guidelines. Practical recommendations are provided describing evidence-based indications as well as interpretation criteria and pitfalls. Monitoring treatment response is the most challenging but insufficiently studied potential application in infection and inflammation imaging.

Predictive biomarkers of response to tocilizumab in giant cell arteritis (GCA): correlations with imaging activity

In the recent EULAR recommendations, ultrasound examination is now recommended as a first-line imaging test in all patients with suspected giant cell arteritis (GCA) and the axillary arteries should be included in the standard exam. As an alternative to ultrasound evaluation, cranial and extracranial arteries can be examined using FDG-PET or MRI. The aim of our study was to observe in a retrospective case series whether there is a correlation between biomarkers and imaging activity in a population of patients followed in real life with GCA treated with prednisone (PDN) and tocilizumab (TCZ). We retrospectively enrolled 68 patients with newly diagnosed GCA between January 2020 and September 2021, followed in real life, who were examined at the Rheumatology Unit of the San Giovanni di Dio Hospital, Florence, Italy. Patients were evaluated at T0-T3-T6-T12-T18-T24 for the following blood tests: ESR, CRP, fibrinogen, platelet count, serum amyloid A (SAA), IL-6, and circulating calprotectin (MRP). Ultrasound examination of the temporal arteries and axillary arteries was assessed at T0 within 7 days of starting treatment with high-dose glucocorticoids and subsequently at T3-T6-T12-T18-T24. A scale from 0 to 3 with semi-quantitative tools (SUV max) was assessed at T0-T12-T24. The evaluation of the correlation coefficient between laboratory and imaging variables has shown that SAA and MRP have the most powerful correlation with the PET score (0.523 and 0.64), and MRP also has an excellent correlation coefficient with the Halo score (0.658). The evaluation of the ROC curves shows for a PET score 3 and SAA values higher than 26 mg/L, sensitivity of 81.5% and specificity of 84.1%, and for a PET score 3 and MRP values higher than 2.3 mcg/mL, sensitivity of 100% and specificity of 76.8%. In this study, we demonstrated that SAA and MRP can be useful as promising tools to detect GCA activity. The study demonstrates a good correlation between the two biomarkers and the imaging activity evaluated by the Halo and PET scores.

MRVAS-introducing a standardized magnetic resonance scoring system for assessing the extent of inflammatory burden in giant cell arteritis

OBJECTIVES

Our aim was to introduce a standardized system for assessing the extent of GCA on MRI, i.e. the Magnetic Resonance Vasculitis Activity Score (MRVAS). To obtain a comprehensive view, we used an extensive MRI protocol including cranial vessels and the aorta with its branches. To test reliability, MRI was assessed by four readers with different levels of experience.

METHODS

A total of 80 patients with suspected GCA underwent MRI of the cranial arteries and the aorta and its branches (20 vessel segments). Every vessel was rated dichotomous [inflamed (coded as 1) or not (coded as 0)], providing a summed score of 0-20. Blinded readers [two experienced radiologists (ExR) and two inexperienced radiologists (InR)] applied the MRVAS on an individual vessel and an overall level (defined as the highest score of any of the individual vessel scores). To determine interrater agreement, Cohen's κ was calculated for pairwise comparison of each reader for individual vessel segments. Intraclass correlation coefficients (ICCs) were used for the MRVAS.

RESULTS

Concordance rates were excellent for both subcohorts on an individual vessel-based (GCA: ICC 0.95; non-GCA: ICC 0.96) and overall MRVAS level (GCA: ICC 0.96; non-GCA: ICC 1.0). Interrater agreement yielded significant concordance (P < 0.001) for all pairs (κ range 0.78-0.98). No significant differences between ExRs and InRs were observed (P = 0.38).

CONCLUSION

The proposed MRVAS allows standardized scoring of inflammation in GCA and achieved high agreement rates in a prospective setting.

A Rare Case of Extracranial Giant Cell Arteritis in a Patient With Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs, and its coexistence with Giant Cell Arteritis (GCA) is extremely rare. We present, to our knowledge, the first reported case of a 56-year-old woman with SLE and extracranial GCA who presented with chest pain as the cardinal symptom. The diagnosis was subsequently confirmed by imaging studies, ruling out Takayasu arteritis and SLE-related vasculitis. She required treatment with glucocorticoids and tocilizumab, showing a satisfactory evolution. Accurate diagnosis was key to preventing serious vascular complications and achieving favorable clinical recovery.

Temporal artery biopsy in giant cell arteritis: clinical perspectives and histological patterns

Although its role has been debated, temporal artery biopsy (TAB) remains the gold standard for the diagnosis of cranial giant cell arteritis (GCA). The specificity of TAB is excellent and the sensitivity, albeit lower, is comparable with other diagnostic modalities used for the diagnosis of GCA. This outpatient procedure has a low rate of complications and is well integrated in the majority of healthcare systems. The length of the specimen, the number of the examined sections and the prolonged use of glucocorticoids before the biopsy may affect the outcome of the TAB as diagnostic tool. The typical histological findings in GCA are often characterized by granulomatous inflammation with infiltration of mononuclear cells with or without the presence of giant cell, varying degrees of external and internal elastic lamina damage and intimal thickening. Overlooking signs of inflammation in the adventitia and in connective tissue surrounding the temporal artery may lead to false negative results. The distinction between healed arteritis and age-related atherosclerosis may be challenging.

Imaging Findings in Giant Cell Arteritis: Don't Turn a Blind Eye to the Obvious!

Giant cell arteritis (GCA) is the most common primary large vessel systemic vasculitis in the Western World. Even though the involvement of scalp and intracranial vessels has received much attention in the neuroradiology literature, GCA, being a systemic vasculitis, can involve multiple other larger vessels including the aorta and its major head and neck branches. Herein, the authors present a pictorial review of the various cranial, extracranial, and orbital manifestations of GCA. An increased awareness of this entity may help with timely and accurate diagnosis, helping expedite therapy and preventing serious complications.

[News on the imaging of large vessel vasculitis]

Large vessel vasculitis, including giant cell arteritis (GCA) and Takayasu arteritis (TAK), are autoimmune diseases primarily affecting the aorta and its branches. GCA is the most common primary vasculitis. Inflammatory changes in the vessel walls can cause serious complications such as amaurosis, stroke, and aortic dissection and rupture. Imaging techniques have become an integral part for the diagnosis and monitoring of large vessel vasculitis, allowing for effective disease monitoring. GCA and TAK exhibit similar patterns of vascular distribution. However, the temporal arteries are never involved in TAK, and axillary arteritis occurs more frequently in GCA. In most centers, ultrasound of the temporal and axillary arteries has replaced temporal artery biopsy as the primary diagnostic tool for GCA. In addition to ultrasound, magnetic resonance imaging (MRI), computed tomography (CT), and [18F]-FDG (fluorodeoxyglucose) positron emission tomography-computed tomography (PET) are important, particularly for visualizing the aorta. Moreover, PET-CT is now also capable of assessing the temporal arteries, although it is not yet widely available. In polymyalgia rheumatica (PMR), ultrasound of the shoulder and hip regions is part of the ACR/EULAR classification criteria. MRI allows detailed visualization of additional inflammatory extraarticular manifestations, showing characteristic inflammatory lesions in entheses, tendons, and ligaments. [18F]-FDG-PET-CT also enables the visualization of musculoskeletal inflammation, especially in the shoulder and hip regions, as well as paravertebral areas. Ultrasound can detect subclinical GCA in up to 23% of patients with PMR, which should be treated like GCA. Technological innovations such as new radiotracers and improved MRI imaging could further enhance the diagnosis and monitoring of large vessel vasculitis and PMR, thus playing a crucial role in improving the prognosis through faster initiation of therapy.

Broadening the clinical spectrum of giant cell arteritis: from the classic cranial to the predominantly extracranial pattern of the disease

INTRODUCTION

Giant cell arteritis (GCA) is a large vessel (LV) vasculitis that affects people aged 50 years and older. Classically, GCA was considered a disease that involved branches of the carotid artery. However, the advent of new imaging techniques has allowed us to reconsider the clinical spectrum of this vasculitis.

AREASCOVERED

This review describes clinical differences between patients with the cranial GCA and those with a predominantly extracranial LV-GCA disease pattern. It highlights differences in the frequency of positive temporal artery biopsy depending on the predominant disease pattern and emphasizes the relevance of imaging techniques to identify patients with LV-GCA without cranial ischemic manifestations. The review shows that so far there are no well-established differences in genetic predisposition to GCA regardless of the predominant phenotype.

EXPERT COMMENTARY

The large branches of the extracranial arteries are frequently affected in GCA. Imaging techniques are useful to identify the presence of 'silent' GCA in people presenting with polymyalgia rheumatica or with nonspecific manifestations. Whether these two different clinical presentations of GCA constitute a continuum in the clinical spectrum of the disease or whether they may be related but are definitely different conditions needs to be further investigated.

Imaging Response to Treatment in Rheumatology

This article highlights the crucial role of various imaging techniques in the diagnosis and monitoring of rheumatologic diseases. It provides an overview of the different modalities available for imaging rheumatic diseases, the disease processes they are able to demonstrate, and their utility in the monitoring response to therapy. It emphasizes the need for a multifaceted approach that combines radiography, ultrasound, MR imaging, and PET imaging to gain a comprehensive understanding of disease progression and treatment response. Standardized grading systems along with quantitative imaging techniques are playing an increasing role in monitoring disease activity and assessing response to therapy.

Role and potential of 18F-fluorodeoxyglucose-positron emission tomography-computed tomography in large-vessel vasculitis: a comprehensive review

Large-vessel vasculitis (LVV) is a group of diseases characterized by inflammation of the aorta and its main branches, which includes giant cell arteritis (GCA), polymyalgia rheumatica (PMR), and Takayasu's arteritis (TAK). These conditions pose significant diagnostic and management challenges due to their diverse clinical presentations and potential for serious complications. 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG-PET-CT) has emerged as a valuable imaging modality for the diagnosis and monitoring of LVV, offering insights into disease activity, extent, and response to treatment. 18F-FDG-PET-CT plays a crucial role in the diagnosis and management of LVV by allowing to visualize vessel involvement, assess disease activity, and guide treatment decisions. Studies have demonstrated the utility of 18F-FDG-PET-CT in distinguishing between LVV subtypes, evaluating disease distribution, and detecting extracranial involvement in patients with cranial GCA or PMR phenotypes. Additionally, 18F-FDG-PET-CT has shown promising utility in predicting clinical outcomes and assessing treatment response, based on the correlation between reductions in FDG uptake and improved disease control. Future research should focus on further refining PET-CT techniques, exploring their utility in monitoring treatment response, and investigating novel imaging modalities such as PET-MRI for enhanced diagnostic accuracy in LVV. Overall, 18F-FDG-PET-CT represents a valuable tool in the multidisciplinary management of LVV, facilitating timely diagnosis and personalized treatment strategies to improve patient outcomes.

Increased interest with the introduction of fast-track diagnostic pathway is associated with the regionally increased frequency of giant cell arteritis in Poland: a study based on POLVAS registry data

Slavic populations, such as those in Poland, are considered to have a low prevalence of giant cell arteritis (GCA), although epidemiological data are sparse. The study aimed to compare the reported frequency of GCA in various regions of Poland and analyze the differences between them. We conducted a multicenter, retrospective study of all GCA patients included in the POLVAS registry-the first large multicenter database of patients with vasculitis in Poland. The data from the POLVAS registry were compared with the reported prevalence provided by national insurers from the corresponding regions. A 10-fold increase in the diagnostic rates of GCA was observed in Poland between 2008 and 2019, reaching 8.38 per 100,000 population > 50 years old. It may be attributed to increased interest accompanied by improved diagnostic modalities with the introduction of ultrasound-based, fast-track diagnostic pathways in some centers. However, regional inequities are present, resulting in 10-fold differences (from 2.57 to 24.92) in reported prevalence between different regions. Corticosteroid (CS) monotherapy was the main stem of treatment. Further cooperation and education are needed to minimize regional inequities. This observational study suggests some potential for further increase of the recognizability of GCA and wider use of other than CS monotherapy treatment regimens. We hope that the Polish experience might be interesting and serve as some guidance for the populations where GCA is underdiagnosed.

The utility of 18F-FDG-PET/CT in detecting extracranial large vessel vasculitis in rheumatic polymyalgia or giant cell arteritis. A systematic review and meta-analysis

OBJECTIVE

Systematic review of current evidence to analyze the prevalence of extracranial large vessel vasculitis (LVV) using 18F-FDG PET/CT in patients with polymyalgia rheumatica (PMR) or giant cell arteritis (GCA).

MATERIALS AND METHODS

PubMed and EMBASE were searched and the results were screened by two reviewers. Study quality was assessed using a modified version of the Newcastle-Ottawa scale. Heterogeneity between studies was assessed using the I2 statistic and the Q test. Further subgroup analyses were performed by disease type, study quality, and 18F-FDG PET/CT uptake criteria. Publication bias was assessed by funnel plot and Egger's test.

RESULTS

268 publications were identified, of which 17 met the selection criteria and were included in the meta-analysis. The overall pooled prevalence of extracranial LVV by 18F-FDG PET/CT was 54.5% [95% CI: 42.6%-66.1%]. In patients with GCA the prevalence was significantly higher than in patients with PMR (60.1% vs. 41.8%, P = 0.006). Likewise, studies with a lower risk of bias reported a higher prevalence of extracranial LVV (61.1% vs. 46.9%; P = 0.010). No publication bias was observed.

CONCLUSIONS

The 18F-FDG PET/CT test may be useful in the detection of extracranial LVV, both in patients with PMR or GCA. Such involvement is more frequent in patients with GCA, and may vary depending on the quality of the studies.

Cranial and extracranial manifestations of giant cell arteritis: a single-center observational study

INTRODUCTION

Giant cell arteritis (GCA) presents two major phenotypes - cranial (cGCA) and extracranial (exGCA). exGCA may be overlooked. The study aimed to compare the clinical characteristics between cGCA and exGCA.

METHODS

Electronic medical records of patients treated between January 2015 and July 2023 at the Department of Rheumatology were searched for the diagnosis of GCA. The clinical characteristics of patients with cGCA, exGCA, and overlapping GCA manifestations were compared.

RESULTS

Out of 32 patients with GCA, 20 had cGCA, 7 had exGCA, and 5 had overlap manifestations. The groups did not differ significantly in demographics, clinical signs/symptoms, or laboratory test results. Importantly, the combined group of patients with exGCA and overlap GCA had a statistically significant delay in initiating treatment (median 12 weeks) compared to patients with cGCA (median 4 weeks; p = 0.008).

CONCLUSION

Our study confirmed the insidious nature of exGCA, which lacks distinctive clinical symptoms and consequently leads to delayed treatment.

Prognostic value of 18 FDG-PET at diagnosis and follow-up in giant cell arteritis: An observational restrospective study

OBJECTIVES

To evaluate the ability of 18FDG PET/CT, at diagnosis of giant cell arteritis (GCA) and during follow-up, to predict occurrence of relapse in large-vessel GCA (LV-GCA).

METHODS

We conducted a retrospective study using the French Study Group for Large-Vessel Vasculitis (GEFA) network. Data from patients with LV-GCA diagnosed by PET/CT and who had PET/CT in the following year were collected. For each PET/CT, PET vascular activity score (PETVAS) and total vascular score (TVS) were assessed, and their ability to predict the occurrence of subsequent relapse was assessed.

RESULTS

A total of 65 LV-GCA patients were included, of whom 55 had undergone a follow-up PET/CT 3 to 12 months after the diagnosis of GCA. Patients for whom the second PET/CT (PET2) was performed during active GCA were excluded. PETVAS and TVS decreased between PET1 and PET2 in all patients (p < 0.001). There was no correlation between vascular activity scores in PET2 and time to prednisone taper. For relapse prediction, at PET1, the AUC of the TVS and PETVAS were respectively 51.9 and 41.9 at 6 months, 55.3 and 49.7 at 1 year, 55 and 55.7 at 2 years. For PET2, the AUC were respectively 46.1 and 46.7 at 6 months, 52.1 and 48.9 at 1 year, 58.4 and 52.3 at 2 years.

CONCLUSION

PET vascular activity scores at diagnosis and at follow-up PET/CT performed outside a period of GCA activity do not display high performance to predict the occurrence of subsequent relapse in LV-GCA patients.

Vascular ultrasound as a follow-up tool in patients with giant cell arteritis: a prospective observational cohort study

Objectives

To evaluate relapses in giant cell arteritis (GCA), investigate the utility of vascular ultrasound to detect relapses, and develop and assess a composite score for GCA disease activity (GCAS) based on clinical symptoms, ultrasound imaging activity, and C-reactive protein (CRP).

Methods

Patients with GCA were prospectively followed with scheduled visits, including assessment for clinical relapse, protocol ultrasound examination, and CRP. At each visit, patients were defined as having ultrasound remission or relapse. GCAS was calculated at every visit.

Results

The study included 132 patients, with a median follow-up time of 25 months [interquartile range (IR) 21]. The clinical relapse rate was 60.6%. There were no differences in relapse rates between GCA subtypes (cranial-GCA, large vessel (LV)-GCA, and mixed-GCA) (p = 0.83). Ultrasound yielded a sensitivity of 61.2% and a specificity of 72.3% for diagnosing GCA- relapse in our cohort. In 7.7% of follow-up visits with clinical relapses, neither high CRP nor findings of ultrasound relapse were registered. In comparison, in 10.3% of follow-up visits without symptoms of clinical relapse, there were both a high CRP and findings of ultrasound relapse.

Conclusion

We found moderate sensitivity and specificity for ultrasound as a monitoring tool for relapse in this prospective cohort of GCA patients. The extent or subtype of vasculitis at the diagnosis did not influence the number of relapses. Based on a combination of clinical symptoms, elevated CRP, and ultrasound findings, a composite score for GCA activity is proposed.

Should all patients with polymyalgia rheumatica have a vascular ultrasound assessment?

There is a growing appreciation that both giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are closely interrelated conditions that have significant overlap in aetiology, clinical characteristics and treatment regimens. Subclinical GCA in PMR is becoming increasingly recognised, and there is evolving evidence that this may be a more aggressive disease phenotype than PMR. Ultrasound (US) lends itself well as a screening tool for GCA in PMR; it is inexpensive, non-invasive, widely available, lacks ionising radiation, may be performed at the bedside and is recommended by EULAR as a first-line investigation for suspected GCA. There is insufficient evidence to currently recommend that all patients with PMR should have a US assessment for vascular involvement. However, as clinical and laboratory parameters alone do not accurately diagnose patients with subclinical GCA, we suggest that vascular US will be increasingly performed by rheumatologists in practice to identify these patients with PMR, preferably as part of larger prospective outcome studies.

High-frequency ultrasound with superb microvascular imaging: a potential tool for ultrasound assessment in patients with giant cell arteritis

Objective

The objective of this study was 2-fold: first, to evaluate whether superb microvascular imaging (SMI) could be used to visualize neovascularization in temporal arteries, and, second, to evaluate the diagnostic performance of high frequency ultrasound with SMI using an extended protocol in patients with suspected giant cell arteritis (GCA).

Methods

This retrospective study comprised 120 patients consecutively examined with an extended CDU protocol (temporal, facial, axillary, subclavian, brachiocephalic, and carotid arteries) between 2020 and 2022. Of all patients, 107 had no previous GCA diagnosis and 13 had a previous GCA diagnosis. SMI was used to evaluate neovascularization in the temporal arteries. Arteritis were characterized as low- or medium-echogenic, homogeneous wall thickening, with or without a positive compression sign in the temporal arteries. The Halo count, i.e., the number of temporal and axillary artery segments with signs of arteritis, was evaluated. The reference was clinically diagnosed GCA confirmed after ≥6-month follow-up.

Results

Of the eligible 107 patients with new suspected GCA, 33 (31%) received a clinical GCA diagnosis. Neovascularization was detected in 14 patients (43%). Patients with neovascularization displayed a higher halo count [median 6 (25th-75th percentile 4.75-7) vs. 3 (2-4-4), p = 0.005]. CDU of only the temporal arteries showed sensitivity and specificity (95% confidence intervals) of 94% (80-100%) and 100% (95-100%), respectively. The addition of extra-cranial arteries increased the sensitivity to 100%. Of the 13 patients investigated for suspected relapse, three had a clinically confirmed relapse. One of them displayed neovascularization together with other signs of inflammation.

Conclusions

We show for the first time that inflammatory neovascularization of the temporal arteries can be detected by SMI. Neovascularization is associated with a more-widespread cranial disease. The value of neovascularization should be further investigated, especially for the detection of GCA relapse.

The DANIsh VASculitis cohort study: protocol for a national multicenter prospective study including incident and prevalent patients with giant cell arteritis and polymyalgia rheumatica

The DANIsh VASculitis cohort study, DANIVAS, is an observational national multicenter study with the overall aim to prospectively collect protocolized clinical data and biobank material from patients with polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) diagnosed and/or followed at Danish rheumatology departments. A long-term key objective is to investigate whether the use of new clinically implemented diagnostic imaging modalities facilitates disease stratification in the GCA-PMR disease spectrum. In particular, we aim to evaluate treatment requirements in GCA patients with and without large-vessel involvement, treatment needs in PMR patients with and without subclinical giant cell arteritis, and the prognostic role of imaging with respect to aneurysm development. Hence, in GCA and PMR, imaging stratification is hypothesized to be able to guide management strategies. With an established infrastructure within rheumatology for clinical studies in Denmark, the infrastructure of the Danish Rheumatologic Biobank, and the possibility to cross-link data with valid nationwide registries, the DANIVAS project holds an exceptional possibility to collect comprehensive real-world data on diagnosis, disease severity, disease duration, treatment effect, complications, and adverse events. In this paper, we present the research protocol for the DANIVAS study. Clinical trial registration: https://clinicaltrials.gov/, identifier NCT05935709.

A systematic review for the evidence of recommendations and guidelines in hybrid nuclear cardiovascular imaging

OBJECTIVES

This study aimed to evaluate the level of evidence of expert recommendations and guidelines for clinical indications and procedurals in hybrid nuclear cardiovascular imaging.

METHODS

From inception to August 2023, a PubMed literature analysis of the latest version of guidelines for clinical hybrid cardiovascular imaging techniques including SPECT(/CT), PET(/CT), and PET(/MRI) was performed in two categories: (1) for clinical indications for all-in primary diagnosis; subgroup in prognosis and therapy evaluation; and for (2) imaging procedurals. We surveyed to what degree these followed a standard methodology to collect the data and provide levels of evidence, and for which topic systematic review evidence was executed.

RESULTS

A total of 76 guidelines, published between 2013 and 2023, were included. The evidence of guidelines was based on systematic reviews in 7.9% of cases, non-systematic reviews in 47.4% of cases, a mix of systematic and non-systematic reviews in 19.7%, and 25% of guidelines did not report any evidence. Search strategy was reported in 36.8% of cases. Strengths of recommendation were clearly reported in 25% of guidelines. The notion of external review was explicitly reported in 23.7% of cases. Finally, the support of a methodologist was reported in 11.8% of the included guidelines.

CONCLUSION

The use of evidence procedures for developing for evidence-based cardiovascular hybrid imaging recommendations and guidelines is currently suboptimal, highlighting the need for more standardized methodological procedures.

Multimodality imaging to assess diagnosis and evaluate complications of large vesselarteritis

Different types of vasculitis can be distinguished according to the blood vessel's size that is preferentially affected: large-vessel, medium-vessel, and small-vessel vasculitides. Giant cell arteritis (GCA) and Takayasu's arteritis (TAK) are the main forms of large-vessel vasculitis, and may lead to lumen narrowing. Clinical manifestations of arterial narrowing on the short- and long term include vision loss, stroke, limb ischemia, and heart failure. Imaging tools are well established diagnostic tests for large-vessel vasculitis and may aid therapy monitoring in selected cases while providing important information regarding the occurrence of vascular damage, tissue and organ complications. This review aims to provide the current status of multimodality imaging for the diagnosis and identification of vascular complications in the field of large vessel vasculitis.

The effect of prednisolone and a short-term prednisolone discontinuation for the diagnostic accuracy of FDG-PET/CT in polymyalgia rheumatica-a prospective study of 101 patients

PURPOSE

2-[18F]Fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) has been suggested as an imaging modality to diagnose polymyalgia rheumatica (PMR). However, the applicability of FDG-PET/CT remains unclear, especially following glucocorticoid administration. This study aimed to investigate the diagnostic accuracy of FDG-PET/CT before and during prednisolone treatment, as well as following short-term prednisolone discontinuation.

METHODS

Treatment naïve suspected PMR patients were clinically diagnosed at baseline and subsequently had an FDG-PET/CT performed. Patients diagnosed with PMR were administered prednisolone following the first FDG-PET/CT and had a second FDG-PET/CT performed after 8 weeks of treatment. Subsequently, prednisolone was tapered with short-term discontinuation at week 9 followed by a third FDG-PET/CT at week 10. An FDG-PET/CT classification of PMR/non-PMR was applied, utilizing both the validated Leuven score and a dichotomous PMR score. The final diagnosis was based on clinical follow-up after 1 year.

RESULTS

A total of 68 and 27 patients received a final clinical diagnosis of PMR or non-PMR. A baseline FDG-PET/CT classified the patients as having PMR with a sensitivity/specificity of 86%/63% (Leuven score) and 82%/70% (dichotomous score). Comparing the subgroup of non-PMR with inflammatory diseases to the PMR group demonstrated a specificity of 39%/54% (Leuven/dichotomous score). After 8 weeks of prednisolone treatment, the sensitivity of FDG-PET/CT decreased to 36%/41% (Leuven/dichotomous score), while a short-term prednisolone discontinuation increased the sensitivity to 66%/60%.

CONCLUSION

FDG-PET/CT has limited diagnostic accuracy for differentiating PMR from other inflammatory diseases. If FDG-PET/CT is intended for diagnostic purposes, prednisolone should be discontinued to enhance diagnostic accuracy.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT04519580). Registered 17th of August 2020.

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

BACKGROUND

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.

OBJECTIVE

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.

DESIGN

Prospective multicenter study with a 2-year follow-up. (ClinicalTrials.gov: NCT02703922).

SETTING

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.

PATIENTS

165 patients with high clinical suspicion of GCA, aged 79 years (IQR, 73 to 85 years).

INTERVENTION

The diagnostic procedure was ultrasound, performed less than 7 days after initiation of corticosteroid therapy. Only ultrasound-negative patients underwent TAB.

MEASUREMENTS

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.

RESULTS

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%).

LIMITATION

Small sample size, no blinding of ultrasound and TAB results, lack of an objective gold-standard comparator, and single diagnostic strategy.

CONCLUSION

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.

PRIMARY FUNDING SOURCE

Tender "Recherche CH-CHU Poitou-Charentes 2014."

Cranial involvement in giant cell arteritis

Since its first clinical description in 1890, extensive research has advanced our understanding of giant cell arteritis, leading to improvements in both diagnosis and management for affected patients. Imaging studies have shown that the disease frequently extends beyond the typical cranial arteries, also affecting large vessels such as the aorta and its proximal branches. Meanwhile, advances in comprehending the underlying pathophysiology of giant cell arteritis have given rise to numerous potential therapeutic agents, which aim to minimise the need for glucocorticoid treatment and prevent flares. Classification criteria for giant cell arteritis, as well as recommendations for management, imaging, and treat-to-target have been developed or updated in the last 5 years, and current research encompasses a broad spectrum covering basic, translational, and clinical research. In this Series paper, we aim to discuss the current understanding of giant cell arteritis with cranial manifestations, describe the clinical approach to this condition, and explore future directions in research and patient care.

[Clinical characteristics and follow-up of 60 patients with recent diagnosis of giant cell arteritis, NEWTON study]

INTRODUCTION

The management of giant cell arteritis (GCA) has evolved with the arrival of tocilizumab (TCZ) and the use of PET/CT. Our objective is to describe the characteristics and followup of patients with recent diagnosis of GCA in current care.

PATIENTS AND METHODS

The NEWTON cohort is a monocentric retrospective cohort based on data collected from 60 GCA patients diagnosed between 2017 and 2022 according to the ACR/EULAR 2022 criteria.

RESULTS

The median age at diagnosis was 73 [68.75; 81] years old. At diagnosis, the main manifestations were unusual temporal headaches in 48 (80 %) and an inflammatory syndrome in 50 (83 %) patients. Temporal artery biopsy confirmed the diagnosis in 49/58 (84 %) patients. Doppler of the temporal arteries found a halo in 12/23 (52 %) patients. The PET/CT found hypermetabolism in 19/43 (44 %) patients. Prednisone was stopped in 17.5 [12.75; 24.25] months. During follow-up, 22 (37 %) patients received TCZ. At least one complication of corticosteroid therapy was observed in 22 (37 %) patients. After a median follow-up of 24 [12; 42] months, 25 (42 %) patients relapsed. At the end of the follow-up, 29 (48.3 %) patients were weaned from corticosteroid therapy and 15 (25 %) were on TCZ.

CONCLUSION

Despite the increasing use of TCZ in the therapeutic arsenal and of the PET/CT in the imaging tools of GCA patients, relapses and complications of corticosteroid therapy remain frequent, observed in more than a third of patients.

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 power of us: breaking barriers and bridging the gap of ultrasound in rheumatology to empower a new generation

OBJECTIVE

This study assesses musculoskeletal ultrasound (MSUS) knowledge, attitudes, and practices among young rheumatologists in Mexico, aiming to identify barriers and facilitators to its clinical use.

METHODS

An online survey distributed to a network of young rheumatologists captured demographics, institutional, and personal MSUS information. Multivariable analysis identified factors associated with positive MSUS attitudes.

RESULTS

Ninety-six rheumatologists (39.18% national response rate) completed the survey. Of respondents (54.2% females, median age 35.1 years), 81.2% deemed MSUS necessary in clinical rheumatology. The main barriers included limited training access (56.2%) and required training time (54.1%). Lack of scientific evidence was not a major barrier (60.4%). Positive MSUS attitudes were associated with learning from conferences (p = 0.029) and colleagues (p = 0.005), formal (p = 0.043), and in-person training (p = 0.020), MSUS use in practice (p = 0.027), and use by radiologists in their institute (p < 0.001). Interest in learning MSUS (88.5%) was significantly higher in those with positive attitudes (94.4%, p < 0.001). Elastic net analysis identified key drivers, including learning MSUS from conferences, colleagues, and in residency; using MSUS in practice; respondent-performed MSUS; and MSUS use by radiologists. Statistically significant associations were found with using MSUS for synovitis/inflammatory joint disease (OR = 1.43, 95% CI 1.00-2.05) and MSUS use by radiologists in respondent's institutes (OR = 1.70, 95% CI 1.20-2.90).

CONCLUSION

Most young rheumatologists in Mexico recognize the necessity of MSUS in clinical practice. By addressing identified barriers, encouraging rheumatologist-radiologist collaboration, and establishing a regulatory body to certify rheumatologist's MSUS experience, there is an opportunity to empower them with the necessary skills for effective MSUS use, ultimately benefiting patient care.

Large vessel giant cell arteritis

Giant cell arteritis is the principal form of systemic vasculitis affecting people over 50. Large-vessel involvement, termed large vessel giant cell arteritis, mainly affects the aorta and its branches, often occurring alongside cranial giant cell arteritis, but large vessel giant cell arteritis without cranial giant cell arteritis can also occur. Patients mostly present with constitutional symptoms, with localising large vessel giant cell arteritis symptoms present in a minority of patients only. Large vessel giant cell arteritis is usually overlooked until clinicians seek to exclude it with imaging by ultrasonography, magnetic resonance angiography (MRA), computed tomography angiography (CTA), or [18F]fluorodeoxyglucose-PET-CT. Although the role of imaging in treatment monitoring remains uncertain, imaging by MRA or CTA is crucial for identifying aortic aneurysm formation during patient follow up. In this Series paper, we define the large vessel subset of giant cell arteritis and summarise its clinical challenges. Furthermore, we identify areas for future research regarding the management of large vessel giant cell arteritis.

[Laboratory diagnostics for vasculitis beyond antineutrophil cytoplasmatic autoantibodies]

The diagnosis of systemic vasculitis (SV) is a major clinical challenge due to the very different forms of presentation and requires an interdisciplinary approach. Targeted laboratory diagnostics support making the diagnosis, differential diagnosis and classification and are also a key component in the detection of active organ manifestations and treatment complications. The basic laboratory tests include the erythrocyte sedimentation rate (ESR), C‑reactive protein (CRP), blood count, serum creatinine, urinalysis, specific autoantibodies, complement, immunoglobulins, cryoglobulins and hepatitis B and C serology. Antineutrophil cytoplasmic autoantibodies (ANCA), antiglomerular basement membrane antibodies (anti-GBM antibodies) and anti-C1q antibodies are valuable laboratory markers for the diagnosis of the various forms of small vessel vasculitis. There are no specific laboratory tests for the diagnosis of medium and large vessel vasculitis. Despite advances in our understanding of the pathogenesis of vasculitis, no biomarkers have yet been identified that can be reliably used to guide treatment or that are useful in distinguishing vasculitis from other inflammatory diseases such as infections or treatment complications.

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.

PET/CT in Inflammatory and Auto-immune Disorders: Focus on Several Key Molecular Concepts, FDG, and Radiolabeled Probe Perspectives

Chronic immune diseases mainly include autoimmune and inflammatory diseases. Managing chronic inflammatory and autoimmune diseases has become a significant public health concern, and therapeutic advancements over the past 50 years have been substantial. As therapeutic tools continue to multiply, the challenge now lies in providing each patient with personalized care tailored to the specifics of their condition, ushering in the era of personalized medicine. Precise and holistic imaging is essential in this context to comprehensively map the inflammatory processes in each patient, identify prognostic factors, and monitor treatment responses and complications. Imaging of patients with inflammatory and autoimmune diseases must provide a comprehensive view of the body, enabling the whole-body mapping of systemic involvement. It should identify key cellular players in the pathology, involving both innate immunity (dendritic cells, macrophages), adaptive immunity (lymphocytes), and microenvironmental cells (stromal cells, tissue cells). As a highly sensitive imaging tool with vectorized molecular probe capabilities, PET/CT can be of high relevance in the management of numerous inflammatory and autoimmune diseases. Relying on key molecular concepts of immunity, the clinical usefulness of FDG-PET/CT in several relevant inflammatory and immune-inflammatory conditions, validated or emerging, will be discussed in this review, together with radiolabeled probe perspectives.