Faster steroid-free remission with tocilizumab compared to methotrexate in giant cell arteritis: a real-life experience in two reference centres.

Glucocorticoids (GCs) are still the mainstay of treatment of giant cell arteritis (GCA). Although GCs are highly effective in GCA, the high burden of toxicity of GCs as well as the disease relapse during GC tapering is well documented. To compare the efficacy and rapidity of TCZ and MTX as steroid-sparing agents in a real-life cohort of GCA patients. A retrospective analysis was conducted including patients with newly diagnosed GCA from the Rheumatology Units of Udine and Rome. The inclusion criterion was the treatment with TCZ or MTX as first steroid-sparing drug. 112 GCA patients (81 females) with a median age of 70 (IQ 65-75) years were collected. Thirty-one out of 112 (27.7%) patients were treated with TCZ (162 mg/week), while 81/112 (72.3%) patients received MTX (up to 20 mg/week) as a GC-sparing agent. At month 6 after GCA onset, 5/31 (16.1%) patients in TCZ group and none in MTX group were in GC-free sustained remission (p value = 0.001). Similarly, at month 12, 64.5% (20/31) and 11.1% (9/81) of patients were in sustained GC-free remission in TCZ and MTX group, respectively (p value <0.001). At month 24 of follow-up, at least one relapse of the disease occurred in 7/31 (22.6%) in TCZ-treated and 28/81 (34.6%) in MTX-treated patients, respectively (p value = 0.22). TCZ allowed a faster discontinuation of steroid therapy than MTX in GCA patients, without increasing the risk of relapse.

Giant cell arteritis and therapeutic response: a dual facet of immunotherapy in metastatic clear cell renal carcinoma.

Immune checkpoint inhibitors have emerged as a promising cancer treatment, allowing significant and long-term therapeutic responses. Nivolumab, an anti-programmed cell death protein-1, is one of the molecules of this therapeutic class with known and manageable side effects. Giant cell arteritis is a rare immune-related adverse event most often manifested by headaches poorly released by common antalgics and can result in visual loss. We report its occurrence in an 80-year-old patient on maintenance nivolumab for metastatic clear cell renal carcinoma. Prompt diagnosis and initiation of glucocorticoid therapy led to symptom improvement and visual recovery.

New-onset of giant cell arteritis with ischemic optic neuropathy following the seventh-dose of COVID-19 mRNA vaccination: A case report and literature review.

Coronavirus disease (COVID-19) vaccines have demonstrated excellent efficacy in reducing the morbidity and severity of the disease. However, some patients have been reported to develop systemic rheumatic diseases, such as rheumatoid arthritis, myocarditis, Guillain-Barre syndrome, and giant cell arteritis (GCA) following COVID-19 vaccination. We present a case of GCA with ischemic optic neuropathy following COVID-19 mRNA vaccination. A 73-year-old woman developed headache, myalgia, scalp tenderness, and jaw claudication 4 days after her seventh dose of the vaccination; she also developed severe visual disturbances 1 month after the vaccination. The blood examination tests showed an increased serum C-reactive protein level and erythrocyte sedimentation rate. The echogram for the temporal artery showed a halo sign. Ophthalmic examination revealed ischemic optic neuropathy in both eyes. The patient was treated with a high-dose glucocorticoid and tocilizumab under the diagnosis of GCA with ischemic optic neuropathy, obtaining mild improvement of the symptoms. This report underscores the need for clinical vigilance and further data collection regarding GCA cases after COVID-19 vaccination.

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.

Antiplatelet therapy to prevent ischemic events in giant cell arteritis: protocol for a systematic review and meta-analysis.

BACKGROUND: Giant cell arteritis (GCA) is the most common systemic vasculitis in adults. Presenting features include new-onset headaches, constitutional symptoms, jaw claudication, polymyalgia rheumatica, and visual symptoms. Arterial inflammation with subsequent stenosis and occlusion may cause tissue ischemia, leading to blindness, strokes, and myocardial infarction. Oral antiplatelet therapy has been hypothesized to reduce GCA-related ischemic events. However, previous studies have demonstrated conflicting results regarding the efficacy of antiplatelet agents in GCA. The objective of this systematic review is to assess the safety and efficacy of antiplatelet therapy for the prevention of these events in adults with giant cell arteritis. METHODS: In this systematic review, we will include randomized controlled trials (RTCs), quasi-randomized trials, non-randomized intervention studies, cohort studies, and case-control studies on patients with new-onset or relapsing GCA. The intervention of interest will be pre-existing use or initiation of an oral antiplatelet medication (aspirin, clopidogrel, prasugrel, or ticagrelor) at GCA onset or relapse. The comparator of interest will be the absence of antiplatelet therapy. Endpoints will be evaluated after 6 and 12 months of follow-up. The primary outcome will be GCA-related ischemic events, including permanent blindness, stroke, myocardial infarction, and ischemic event-related deaths. Adverse events such as major bleeding and death caused by a bleeding event will be assessed. DISCUSSION: GCA-related ischemic events are catastrophic, sudden, often irreversible, and lead to significant morbidity. Antiplatelet agents are affordable, accessible, and could be effective for the prevention of these events. Nevertheless, the potential benefits of platelet aggregation inhibition must be weighed against their associated risk of bleeding. Assessing the efficacy and safety of antiplatelet therapy in GCA is therefore clinically important. SYSTEMATIC REVIEW REGISTRATION: Our systematic review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO, registration number CRD42023441574.

Taper versus discontinuation of tocilizumab in patients with giant cell arteritis: Real-world experience from a tertiary center.

INTRODUCTION: Following the approval of tocilizumab (TCZ) for giant cell arteritis (GCA), recent studies have shown a high relapse frequency after abrupt discontinuation of TCZ. However, a thorough exploration of TCZ tapering compared to abrupt discontinuation has never been undertaken. Likewise, adverse events have only been scarcely investigated in routine care. This study aimed to compare the incidence of relapses in GCA patients undergoing TCZ tapering compared to abrupt discontinuation. METHODS: We performed a single-center retrospective cohort study from 2012 to 2022. Data from GCA patients treated with TCZ was obtained from the Electronic Patients Record. Relapse-free survival is reported in Kaplan-Meier plots and tapering versus abrupt discontinuation were compared using a Wilcoxon-Brewlos-Gehan test. RESULTS: We included 155 patients receiving TCZ treatment for GCA, of which 104 discontinued TCZ. Among the 104 patients discontinuing TCZ, 42 (40 %) experienced a relapse within the first year. A total of 57 patients underwent taper with 6/38 (16 %) and 2/19 (11 %) relapsing while receiving TCZ every second or third week, respectively. In comparison, 59 patients underwent abrupt discontinuation with 27 (46 %) relapsing during follow-up. The patients undergoing abrupt TCZ discontinuation demonstrated a significantly shorter time to relapse compared to all tapered patients (p = 0.02) as well as patients tapered from weekly TCZ treatment to every second week (p < 0.01). Furthermore, 15 % of patients discontinued TCZ due to adverse events. CONCLUSION: This is the first study indicating that TCZ taper induced longer relapse-free survival than abrupt discontinuation, implying that taper may be favored over discontinuation in patients with GCA.

Submacular and Intraretinal Fluid Associated with Arteritic Anterior Ischemic Optic Neuropathy.

Introduction: Anterior ischemic optic neuropathy (AION) is an ischemic disorder of the optic nerve and a common cause of acute, painless, permanent vision loss. It is divided into two types: arteritic AION (AAION) and non-arteritic anterior ischemic optic neuropathy (NAION). Although subretinal fluid associated with optic disc edema has been reported in cases of NAION, it is rarely described in AAION. Case Presentation: An 86-year-old female with a history of polymyalgia rheumatica presented with sudden vision loss in the left eye. Initial examination revealed left pallid optic disc edema with peripapillary hemorrhages. Optical coherence tomography (OCT) of the left macula showed intraretinal and submacular fluid. The patient was started on 50 mg of oral prednisone daily. The diagnosis of giant cell arteritis (GCA) was later confirmed with a positive temporal artery biopsy. Three weeks after presentation, an OCT was completed which demonstrated complete resolution of the intraretinal and submacular fluid. Although the presence of both intraretinal and subretinal fluid has been previously documented in cases of NAION, it is rarely reported in a patient with GCA. Conclusion: This is a newly described case of subretinal and intraretinal fluid in a patient with AAION. We postulate that the pathophysiology behind this is mediated by associated choroidal ischemia leading to altered permeability. OCT is an important imaging modality allowing for signs of GCA to be better characterized.

Central Retinal Artery Occlusion Associated with Takayasu Arteritis.

Takayasu arteritis is a chronic inflammatory vasculitis with granulomatous panarteritis particularly impacting large vessels including the aorta and its branches, especially the subclavian arteries, with clinical manifestation dependent on the involved artery. Sequelae of the active disease vary, including stenosis, occlusions, or aneurysmal dilatations of the large vessels. The prevalence of Takayasu arteritis is higher in the Asian population and in Japan, but quite low in the United States, varying from 0.9-8.4 per million people. Ocular manifestations are rare and lead to a delay in diagnosis and appropriate treatment. Ocular manifestations include Takayasu retinopathy, anterior ischemic optic neuropathy (AION), retinal artery occlusion (RAO) and retinal vein occlusion (RVO). We present two cases in which central retinal artery occlusion (CRAO) was associated with Takayasu arteritis. CRAO is an ophthalmic emergency with an incidence of 1.9 per 100,000 person years in the United States; only 5% of cases are arteritic, which can be observed with inflammatory vasculitides secondary to the formation of immune deposits.

Tocilizumab use in giant cell arteritis: comparing Pharmaceutical Benefits Scheme eligible and ineligible cases in South Australia.

Tocilizumab (TCZ) is increasingly used as a steroid-sparing agent in giant cell arteritis (GCA), but there are strict Pharmaceutical Benefits Scheme (PBS) restrictions for its use in Australia. Patients who do not meet the PBS criteria can obtain TCZ through public hospital individual patient use (IPU) schemes which may not be universally accessible. We compared patients receiving IPU-approved TCZ with patients receiving PBS-subsidised TCZ and found IPU approvals were granted mainly for visual loss, a serious complication of GCA, in patients who otherwise failed to meet PBS criteria. Further studies demonstrating that TCZ is comparatively more effective than prednisolone monotherapy, as well as cost-effective, are needed to substantiate the rationale for expanding PBS approval criteria.

Giant Cell Arteritis with Intracranial and Extracranial Aneurysms: A Case Report and Brief Review of the Literature.

Giant cell arteritis (GCA) is a relatively rare, auto-immune vasculitis, more common in women over age 50. It is important to recognize and treat the disease early to prevent late complications of permanent vision loss. Inflammation-associated weakening of vessel walls involved by GCA may also represent a potential etiology for intracranial aneurysm development. In this report, we describe an atypical presentation of GCA confirmed with temporal artery biopsy with associated manifestations including intracranial right posterior communicating artery aneurysm and extracranial right internal carotid aneurysm. Our patient in a 78-year-old female who presented with progressively worsening headaches that began 10 days prior to admission. These were described as global, non-pulsatile, and located over her occiput. She reported associated jaw soreness while chewing or claudication. Her erythrocyte sedimentation rate (ESR) was elevated at 74 mm/hr. Magnetic resonance angiogram showed a right posterior communicating artery aneurysm measuring 5 mm and a right cervical carotid lengthwise dissecting aneurysm measuring 12 mm. Left temporal artery biopsy confirmed the diagnosis of GCA. High-dose steroid therapy was initiated and was continued for treatment of GCA with resolution of symptoms at her one month follow-up. This case highlights a rare instance of cervical internal carotid aneurysm and intracranial aneurysm associated with GCA, emphasizing the systemic nature of this vasculitis.

Magnetic resonance imaging to monitor disease activity in giant cell arteritis treated with ultra-short glucocorticoids and tocilizumab.

OBJECTIVES: MRI is well established for diagnosing GCA. Its role in monitoring disease activity has yet to be determined. We investigated vascular and musculoskeletal inflammation using MRI in the patients of the GUSTO trial to assess the utility of MRI in monitoring disease activity. METHODS: Eighteen patients with newly diagnosed GCA received 500 mg methylprednisolone intravenously for 3 consecutive days followed by tocilizumab monotherapy from day 3 until week 52. Cranial, thoracic and abdominal MRI exams were performed at baseline (active, new-onset disease), and at weeks 24, 52 (remission on-treatment), and 104 (remission off-treatment). MRI findings typical for PMR as well as extent and severity of vasculitic disease were rated. RESULTS: In total, 673 vascular segments and 943 musculoskeletal regions in 55 thoracic/abdominal MRI and 490 vascular segments in 49 cranial MRI scans of 18 patients were analysed. Vasculitic vessels were still detectable in one in four cranial segments at week 24. At weeks 52 and 104, no cranial vascular segment showed a vasculitic manifestation. Large vessels, except for the ascending aorta, and PMR displayed little or no decrease in inflammatory findings over time. CONCLUSION: Vasculitic manifestations in the cranial vessels normalised after 52 weeks of treatment, whereas large vessel and PMR findings persisted despite lasting full remission. The dynamics of cranial vessel signals suggest that MRI of these arteries might qualify as a potential diagnostic tool for monitoring disease activity and for detecting relapse after 52 weeks of treatment.

Clinical Manifestations and Prognosis of Giant Cell Arteritis: A Retrospective Cohort Study.

The aim of the study was to evaluate the clinical manifestations and survival of patients with giant cell arteritis (GCA). MATERIALS AND METHODS: . A retrospective study included 166 patients with newly diagnosed GCA. Clinical, laboratory, and instrumental data and three sets of classification criteria were used to confirm the diagnosis: the American College of Rheumatology (ACR) 1990, the revised ACR criteria of 2016 and/or the new ACR and European Alliance of Rheumatologic Associations (EULAR) 2022 criteria. Some of the patients underwent instrumental investigations: temporal artery ultrasound Doppler (n = 61), contrast-enhanced computed tomography (n = 5), CT angiography (n = 6), magnetic resonance imaging (n = 4), MR angiography (n = 3), and 18F-FDG PET/CT (n = 47). Overall and recurrence-free survival rates were analyzed using survival tables and Kaplan-Meier method. RESULTS: . The most frequent first manifestations of GCA were headache (81.8%), weakness (64%), fever (63.8%), and symptoms of rheumatic polymyalgia (56.6%). Changes in temporal arteries in color duplex scanning were detected in 44 out of 61 patients. GCs therapy was performed in all patients who agreed to be treated (n = 158), methotrexate was used in 49 out of 158 patients, leflunomide in 9 patients. In 45 (28.5%) out of 158 patients, a stable remission was achieved as a result of GC monotherapy; in 120 (75.9%) patients, long-term maintenance therapy with GCs was required to prevent exacerbations, including 71 (44.9%) patients in combination with methotrexate or other immunosuppressive drugs. The follow-up period of patients with a history of relapses was 21.0 (8.0-54.0) months. Relapses developed in 73 (46.2%) patients. The overall one-year survival rate was 97.1% [95% CI 94.3; 99.9], and the five-year survival rate of patients was 94.6% [95% CI 90.2; 99.0]. The one-year relapse-free survival rate was 86.4% [95% CI 80.5; 92.3], and the five-year relapse-free survival rate was 52.4% [95% CI 42.0; 62.8]. Twelve (7.2%) of 166 patients died. The cause of death was myocardial infarction in two patients, stroke in two patients, and breast cancer in one patient; in the remaining seven cases, the cause of death was not determined. CONCLUSIONS: : Given the high frequency of disease exacerbation, patients with GCA require long-term follow-up, especially during the first year after diagnosis.

Serum leukemia inhibitory factor (LIF) levels in patients with Takayasu's and Giant cell arteritis: A cross-sectional study.

INTRODUCTION AND OBJECTIVES: In this study, we aimed to evaluate LIF levels and its possible relationship with disease activity in patients with Takayasu's (TAK) and Giant cell arteritis (GCA) patients. MATERIALS AND METHODS: 23 Takayasu's arteritis, 9 Giant cell arteritis patients and 25 healthy volunteers were included in the study. Serum LIF levels were measured ELISA. RESULTS: The mean age of Giant cell arteritis patients was statistically significantly higher than the other groups (p<0.001). The rate of women was found to be higher in Takayasu's arteritis (p=0.021). When healthy control, patients with GCA and Takayasu arteritis were compared, there was a difference in LIF values (p=0.018). In subgroup analyzes, LIF values were found to be higher in GCA patients compared to healthy controls (p<0.05). There was no statistically significant correlation between LIF and CRP (Rho=-0.038, p=0.778), ESR (Rho=0.114, p=0.399) and ITAS (Rho=-0.357, p=0.094). While CRP was statistically significantly higher in patients with disease activity (p=0.003), there was no statistically significant difference between patients in terms of ESR and LIF values. While there was a statistically significant relationship between CRP (OR=1.19 [1.03-1.37], p=0.018) and disease activity in univariate analyses, no statistically significant variable was found in multivariable analyses. CONCLUSIONS: LIF values were significantly higher in patients with Giant cell arteritis compared to healthy controls.

Pro-fibrotic effect of the susceptible gene PCSK5 in vascular fibrosis of Takayasu arteritis via TGF-ß and SMAD3 signaling pathway activation.

BACKGROUND: Vascular fibrosis directly causes vascular thickening in Takayasu arteritis (TAK), in which sustained transforming growth factor beta (TGF-ß) activation is critical. Understanding TGF-ß activation regulation and blocking it might yield a therapeutic effect in TAK. Proprotein convertase subtilisin/kexin type 5 (PCSK5) rs6560480 (T/C) is associated with TAK development. In this study, we assessed the association between the PCSK5 rs6560480 genotype and PCSK5 expression in TAK and explored its molecular role in TGF-ß activation and vascular fibrosis development. METHODS: In TAK patients, PCSK5 and TGF-ß expression in plasma and aortic tissue was examined by ELISA and immunohistochemical staining, and PCSK5 rs6560480 was genotyped. The correlation between PCSK5 and extracellular matrix (ECM) expression was examined by Western blotting (WB) and immunohistochemistry staining. Detection by co-immunoprecipitation was performed to detect the interaction between PCSK5 and TGF-ß in adventitial fibroblasts (AAFs). Downstream signaling pathways were detected by WB and validated with appropriate inhibitors. Potential immunosuppressive agents to inhibit the effects of PCSK5 were explored in cell culture and TAK patients. RESULTS: Patients with PCSK5 rs6560480 TT patients had significantly higher PCSK5 levels and more thickened vascular lesions than patients with PCSK5 rs6560480 CT. PCSK5 expression was significantly increased in alpha smooth muscle actin (α-SMA)-positive myofibroblasts in TAK vascular lesions. Overexpressing PCSK5 facilitated TGF-ß and downstream SMAD2/3 activation and ECM expression in AAFs and aorta in in-vitro culture. The mechanistic study supported that PCSK5 activated precursor TGF-ß (pro-TGF-ß) to the mature form by binding the pro-TGF-ß cleavage site. Leflunomide inhibited PCSK5 and pro-TGF-ß binding, decreasing TGF-ß activation and ECM expression, which was also partially validated in leflunomide-treated patients. CONCLUSION: The findings revealed a novel pro-fibrotic mechanism of PCSK5 in TAK vascular fibrosis via TGF-ß and downstream SMAD2/3 pathway activation. Leflunomide might be anti-fibrotic by disrupting PCSK5 and pro-TGF-ß binding, presenting a new TAK treatment approach.

Real-World Biomarkers for Pediatric Takayasu Arteritis.

Childhood-onset Takayasu arteritis (TA) is a rare, heterogeneous disease with limited diagnostic markers. Our objective was to identify and classify all candidates for biomarkers of TA diagnosis in children reported in the literature. A systematic literature review (PRISMA) of MEDLINE, EMBASE, Wiley Cochrane Library, ClinicalTrias.gov, and WHO ICTRP for articles related to TA in the pediatric age group between January 2000 and August 2023 was performed. Data on demographics, clinical features, laboratory measurements, diagnostic imaging, and genetic analysis were extracted. We identified 2026 potential articles, of which 52 studies (81% case series) met inclusion criteria. A total of 1067 TA patients were included with a peak onset between 10 and 15 years. Childhood-onset TA predominantly presented with cardiovascular, constitutional, and neurological symptoms. Laboratory parameters exhibited a low sensitivity and specificity. Imaging predominantly revealed involvement of the abdominal aorta and renal arteries, with magnetic resonance angiography (MRA) being the preferred imaging modality. Our review confirms the heterogeneous presentation of childhood-onset TA, posing significant challenges to recognition and timely diagnosis. Collaborative, multinational efforts are essential to better understand the natural course of childhood-onset TA and to identify accurate biomarkers to enhance diagnosis and disease management, ultimately improving patient outcomes.

Ultrasonography of the superficial temporal and axillary arteries in giant cell arteritis diagnosis.

OBJECTIVES: Giant cell arteritis (GCA) is the main systemic vasculitis in individuals aged ≥ 50 years. Color Doppler ultrasound (CDS) has an established role in GCA diagnosis and management. This study aims to assess the clinical characteristics associated with a positive CDS evaluation and the impact of additional axillary artery examination on diagnostic sensitivity. MATERIAL AND METHODS: We conducted a retrospective analysis of patients undergoing CDS of the superficial temporal arteries, with or without axillary artery assessment, at our hospital, between 2009 and 2023. Patients meeting the new 2022 diagnostic criteria for GCA were included and their characteristics were analyzed according to the presence of the halo sign on CDS. RESULTS: Of the 135 included patients (54 % female, mean age 75 ± 8 years), the halo sign was observed in 57 %, correlating with higher systemic symptom prevalence (61 % vs 42 %, p = 0.035), lower hemoglobin (p < 0.001), and higher erythrocyte sedimentation rate (p = 0.028). The halo sign inversely related to prior corticosteroid therapy (p = 0.033). Patients with axillary halo sign had fewer external carotid symptoms and a higher vertebral halo sign prevalence. Vertebral halo sign was associated with posterior circulation ischemic stroke (65 %, p < 0.001). Axillary artery studies improved diagnostic sensitivity by 9 %. CONCLUSION: In our study, the halo sign correlated with higher systemic symptoms and analytical abnormalities. Axillary artery examination enhanced CDS sensitivity, linked to severe outcomes like stroke. Prior corticosteroid therapy reduced CDS sensitivity. The correlation of clinical, laboratory, and ultrasound findings provides a more comprehensive understanding of GCA pathogenesis and evolution.

Positron Emission Tomography/Computed Tomography in Polymyalgia Rheumatica: When and for What-A Critical Review.

Polymyalgia rheumatica (PMR) is an inflammatory disease common in people aged 50 years and older. This condition is characterized by the presence of pain and stiffness involving mainly the shoulder and pelvic girdle. Besides the frequent association with giant cell arteritis (GCA), several conditions may mimic PMR or present with PMR features. Since the diagnosis is basically clinical, an adequate diagnosis of this condition is usually required. Positron emission tomography/computed tomography (PET-CT) has proved to be a useful tool for the diagnosis of PMR. The use of 18F-FDG-PET imaging appears promising as it provides detailed information on inflammatory activity that may not be evident with traditional methods. However, since PET-CT is not strictly necessary for the diagnosis of PMR, clinicians should consider several situations in which this imaging technique can be used in patients with suspected PMR.

Relapses in giant cell arteritis: Updated review for clinical practice.

Giant cell arteritis (GCA), the most common primary vasculitis in adults, is a granulomatous systemic vasculitis usually affecting the aorta and its major branches, particularly the carotid and vertebral arteries. Although remission can be achieved in most patients with GCA using high-dose glucocorticoids (GC), relapses are frequent, occurring in >40% of GC-only treated patients, mostly during the first two years after diagnosis. Relapsing courses lead to high GC exposure, increasing the risk of treatment-related adverse effects. Although tocilizumab is an efficacious GC-sparing therapy that allows increased sustained remission and reduced cumulative GC doses, relapses are common after drug discontinuation. This narrative review examines the most relevant features of relapses in GCA, including its definition, classification, frequency, clinical, laboratory, and imaging characteristics, chronology, probable pathophysiology, and predictive factors. In addition, we discuss treatment options for relapsing patients and the effect of relapses on patient outcomes.