Development of a diagnostic prediction model for giant cell arteritis by sequential application of Southend Giant Cell Arteritis Probability Score and ultrasonography: a prospective multicentre study.

BACKGROUND: Giant cell arteritis is a critically ischaemic disease with protean manifestations that require urgent diagnosis and treatment. European Alliance of Associations for Rheumatology (EULAR) recommendations advocate ultrasonography as the first investigation for suspected giant cell arteritis. We developed a prediction tool that sequentially combines clinical assessment, as determined by the Southend Giant Cell Arteritis Probability Score (SGCAPS), with results of quantitative ultrasonography. METHODS: This prospective, multicentre, inception cohort study included consecutive patients with suspected new onset giant cell arteritis referred to fast-track clinics (seven centres in Italy, the Netherlands, Spain, and UK). Final clinical diagnosis was established at 6 months. SGCAPS and quantitative ultrasonography of temporal and axillary arteries with three scores (ie, halo count, halo score, and OMERACT GCA Score [OGUS]) were performed at diagnosis. We developed prediction models for diagnosis of giant cell arteritis by multivariable logistic regression analysis with SGCAPS and each of the three ultrasonographic scores as predicting variables. We obtained intraclass correlation coefficient for inter-rater and intra-rater reliability in a separate patient-based reliability exercise with five patients and five observers. FINDINGS: Between Oct 1, 2019, and June 30, 2022, we recruited and followed up 229 patients (150 [66%] women and 79 [34%] men; mean age 71 years [SD 10]), of whom 84 were diagnosed with giant cell arteritis and 145 with giant cell arteritis mimics (controls) at 6 months. SGCAPS and all three ultrasonographic scores discriminated well between patients with and without giant cell arteritis. A reliability exercise showed that the inter-rater and intra-rater reliability was high for all three ultrasonographic scores. The prediction model combining SGCAPS with the halo count, which was termed HAS-GCA score, was the most accurate model, with an optimism-adjusted C statistic of 0·969 (95% CI 0·952 to 0·990). The HAS-GCA score could classify 169 (74%) of 229 patients into either the low or high probability groups, with misclassification observed in two (2%) of 105 patients in the low probability group and two (3%) of 64 of patients in the high probability group. A nomogram for easy application of the score in daily practice was created. INTERPRETATION: A prediction tool for giant cell arteritis (the HAS-GCA score), combining SGCAPS and the halo count, reliably confirms and excludes giant cell arteritis from giant cell arteritis mimics in fast-track clinics. These findings require confirmation in an independent, multicentre study. FUNDING: Royal College of Physicians of Ireland, FOREUM.

Epidemiology of giant cell arteritis in Waikato, Aotearoa New Zealand.

AIM: Giant cell arteritis (GCA) is the most common primary vasculitis in adults over 50 years of age. Our primary objective was to assess the incidence and prevalence of GCA in Waikato in a bid to deepen our understanding of the epidemiology of GCA in Aotearoa New Zealand. METHODS: From January 2014 to December 2022, cases of GCA were identified prospectively and retrospectively through temporal artery ultrasound request lists and temporal artery biopsy histology reports. Using electronic health records, data were collected retrospectively on patient demographics and clinical features. These were used to calculate the incidence, prevalence and standardised mortality ratio (SMR) of GCA in Waikato. RESULTS: There were 214 patients diagnosed with GCA over the 9-year period. The majority of patients were European (93.9%, 201/214) with Maori patients being significantly younger than European patients. The mean annual incidence of clinical GCA was 14.7 per 100,000 people over 50 years (95% confidence interval [CI] 12.7-16.6). The SMR was 1.18 (95% CI 0.83-1.52). CONCLUSION: This is the largest study to date on the epidemiology of GCA in Aotearoa New Zealand. The incidence of GCA is comparable to other studies performed in Aotearoa New Zealand and appears to be stable over time. GCA is uncommon in Maori, Pacific Islander and Asian ethnic groups.

Performance of a fast-track pathway for giant cell arteritis in Waikato, Aotearoa New Zealand.

AIMS: Giant cell arteritis (GCA) is the most common primary vasculitis in adults over 50 years of age. To facilitate early diagnosis and reduce harms from corticosteroids and temporal artery biopsies, fast-track pathways have been established. We review the benefits of the fast-track pathway set up in Waikato, Aotearoa New Zealand. METHODS: Patients were collected prospectively as part of the fast-track pathway from 2014 to 2022. Their records were then reviewed retrospectively to collect data on clinical features, investigations and treatment. RESULTS: There were 648 individual patients over the study period who had a colour Doppler ultrasound (CDUS) of the temporal arteries. There were 17 true positive CDUS, giving a sensitivity of 10.3% (95% confidence interval [CI] 6.3-15.5%) and specificity of 99.8% (95% CI 99.1-100%). Patients with GCA and a positive scan had significantly fewer steroids than those with GCA and a negative scan (p=0.0037). There were 376 patients discharged after a CDUS who did not have a diagnosis of GCA, resulting in reduced corticosteroid and temporal artery biopsy exposure. CONCLUSIONS: This is a real-life study that reflects the benefits of fast-track pathways in Aotearoa New Zealand to patients and healthcare systems. It also shows the effect of corticosteroids on positive CDUS, an important consideration when setting up an fast-track pathway.

Halo sign on temporal artery ultrasound versus temporal artery biopsy for giant cell arteritis.

BACKGROUND: Giant cell arteritis (GCA) is a systemic, inflammatory vasculitis primarily affecting people over the age of 50 years. GCA is treated as a medical emergency due to the potential for sudden, irreversible visual loss. Temporal artery biopsy (TAB) is one of the five criteria of the American College of Rheumatology (ACR) 1990 classification, which is used to aid the diagnosis of GCA. TAB is an invasive test, and it can be slow to obtain a result due to delays in performing the procedure and the time taken for histopathologic assessment. Temporal artery ultrasonography (US) has been demonstrated to show findings in people with GCA such as the halo sign (a hypoechoic circumferential wall thickening due to oedema), stenosis or occlusion that can help to confirm a diagnosis more swiftly and less invasively, but requiring more subjective interpretation. This review will help to determine the role of these investigations in clinical practice. OBJECTIVES: To evaluate the sensitivity and specificity of the halo sign on temporal artery US, using the ACR 1990 classification as a reference standard, to investigate whether US could be used as triage for TAB. To compare the accuracy of US with TAB in the subset of paired studies that have obtained both tests on the same patients, to investigate whether it could replace TAB as one of the criteria in the ACR 1990 classification. SEARCH METHODS: We used standard Cochrane search methods for diagnostic accuracy. The date of the search was 13 September 2022. SELECTION CRITERIA: We included all participants with clinically suspected GCA who were investigated for the presence of the halo sign on temporal artery US, using the ACR 1990 criteria as a reference standard. We included studies with participants with a prior diagnosis of polymyalgia rheumatica. We excluded studies if participants had had two or more weeks of steroid treatment prior to the investigations. We also included any comparative test accuracy studies of the halo sign on temporal artery US versus TAB, with use of the 1990 ACR diagnostic criteria as a reference standard. Although we have chosen to use this classification for the purpose of the meta-analysis, we accept that it incorporates unavoidable incorporation bias, as TAB is itself one of the five criteria. This increases the specificity of TAB, making it difficult to compare with US. We excluded case-control studies, as they overestimate accuracy, as well as case series in which all participants had a prior diagnosis of GCA, as they can only address sensitivity and not specificity. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the studies for inclusion in the review. They extracted data using a standardised data collection form and employed the QUADAS-2 tool to assess methodological quality. As not enough studies reported data at our prespecified halo threshold of 0.3 mm, we fitted hierarchical summary receiver operating characteristic (ROC) models to estimate US sensitivity and also to compare US with TAB. We graded the certainty of the evidence using the GRADE approach. MAIN RESULTS: Temporal artery ultrasound was investigated in 15 studies (617 participants with GCA out of 1479, 41.7%), with sample sizes ranging from 20 to 381 participants (median 69). There was wide variation in sensitivity with a median value of 0.78 (interquartile range (IQR) 0.45 to 0.83; range 0.03 to 1.00), while specificity was fair to good in most studies with a median value of 0.91 (IQR 0.78 to 1.00; range 0.40 to 1.00) and four studies with a specificity of 1.00. The hierarchical summary receiver operating characteristic (HSROC) estimate of sensitivity (95% confidence interval (CI)) at the high specificity of 0.95 was 0.51 (0.21 to 0.81), and 0.84 (0.58 to 0.95) at 0.80 specificity. We considered the evidence on sensitivity and specificity as of very low certainty due to risk of bias (-1), imprecision (-1), and inconsistency (-1). Only four studies reported data at a halo cut-off > 0.3 mm, finding the following sensitivities and specificities (95% CI): 0.80 (0.56 to 0.94) and 0.94 (0.81 to 0.99) in 55 participants; 0.10 (0.00 to 0.45) and 1.00 (0.84 to 1.00) in 31 participants; 0.73 (0.54 to 0.88) and 1.00 (0.93 to 1.00) in 82 participants; 0.83 (0.63 to 0.95) and 0.72 (0.64 to 0.79) in 182 participants. Data on a direct comparison of temporal artery US with biopsy were obtained from 11 studies (808 participants; 460 with GCA, 56.9%). The sensitivity of US ranged between 0.03 and 1.00 with a median of 0.75, while that of TAB ranged between 0.33 and 0.92 with a median of 0.73. The specificity was 1.00 in four studies for US and in seven for TAB. At high specificity (0.95), the sensitivity of US and TAB were 0.50 (95% CI 0.24 to 0.76) versus 0.80 (95% CI 0.57 to 0.93), respectively, and at low specificity (0.80) they were 0.73 (95% CI 0.49 to 0.88) versus 0.92 (95% CI 0.69 to 0.98). We considered the comparative evidence on the sensitivity of US versus TAB to be of very low certainty because specificity was overestimated for TAB since it is one of the criteria used in the reference standard (-1), together with downgrade due to risk of bias (-1), imprecision (-1), and inconsistency (-1) for both sensitivity and specificity. AUTHORS' CONCLUSIONS: There is limited published evidence on the accuracy of temporal artery US for detecting GCA. Ultrasound seems to be moderately sensitive when the specificity is good, but data were heterogeneous across studies and either did not use the same halo thickness threshold or did not report it. We can draw no conclusions from accuracy studies on whether US can replace TAB for diagnosing GCA given the very low certainty of the evidence. Future research could consider using the 2016 revision of the ACR criteria as a reference standard, which will limit incorporation bias of TAB into the reference standard.

Eosinophilic giant cell arteritis: A different subset of disease?

OBJECTIVES: To describe the clinical findings, response to therapy and course of patients with transmural eosinophilic infiltration at temporal artery biopsy (TAB). METHODS: The study consisted of a retrospective cohort of 254 consecutive GCA patients with evidence of transmural inflammation at TAB seen at the Santa Maria Nuova Hospital over a 28-year period. The findings of the 22 patients with eosinophilic infiltration (≥ 20 eosinophils/hpf) at TAB were compared with those of 232 patients without. Among these 232 patients, we sampled 42 GCA patients matched for age, sex and follow-up duration to the 22 with eosinophilic infiltration, to compare allergic manifestations. RESULTS: GCA patients with eosinophilic infiltration compared to those without presented more frequently cranial symptoms (p = 0.052), headaches (p = 0.005), abnormalities of TAs at physical examination (p = 0.045), jaw claudication (p = 0.024), and systemic manifestations (p = 0.016) and had higher CRP levels at diagnosis (p = 0.001). Regarding histological lesions, a severe transmural inflammation, laminar necrosis and intraluminal acute thrombosis were more frequently observed in patients with eosinophilic infiltration (p = 0.066, p < 0.001, and p = 0.010, respectively). Long-term remission and flares were similar in the two groups. When 21 GCA patients with eosinophilic infiltration were compared to 42 without, blood eosinophilic counts at diagnosis were normal and no patients had evidence or developed allergic manifestations and/or clinical findings of systemic necrotizing vasculitis. CONCLUSION: Patients with transmural eosinophilic infiltration represent a subset of GCA with cranial disease and more severe inflammation.

Temporal artery ultrasonography for the diagnosis of giant cell arteritis: a case report.

Orofacial pain is a worldwide pain problem, with many patients unable to find appropriate diagnosis and treatment. Orofacial pain includes pain arising from the odontogenic and nonodontogenic structures in the head and neck region. Dental clinicians need to have a thorough knowledge and skill to diagnose, manage, and treat patients with odontogenic pain or refer patients for treatment of nonodontogenic pain to specialists such as orofacial pain specialists, neurologists, otolaryngologists, and rheumatologists. More often, dental practitioners diagnose patients with a temporomandibular disorder (TMD), and when treatment is ineffective, term it "atypical facial pain." The first requirement for effective treatment is an accurate diagnosis. Dental clinicians must be aware of giant cell arteritis (GCA), a chronic large-vessel vasculitis, primarily affecting adults over the age of 50 years, as it frequently mimics and is misdiagnosed as TMD. GCA is associated with loss of vision, and stroke and can be a life-threatening disorder. Therefore, diagnostic testing for GCA and differential diagnosis should be common knowledge in the armamentarium of all dental clinicians. Historically, temporal artery biopsy was considered the definitive diagnostic test for GCA. Temporal artery ultrasound (TAUSG), a safe and noninvasive imaging modality, has replaced the previous diagnostic gold standard for GCA, the temporal artery biopsy, owing to its enhanced diagnostic capabilities and safety profile. The present case report describes a patient with GCA, and the role TAUSG played in the diagnosis. Case report: A 72-year-old woman presented with left-sided facial pain, jaw claudication, dysesthesia of the tongue, and episodic loss of vision of 2 years' duration. She was diagnosed with and treated for a myriad of dental conditions including endodontia and temporomandibular joint therapy with no benefit. A thorough history and physical examination, combined with serologic analysis, led to the diagnosis of GCA and TAUSG, which confirmed the diagnosis. Conclusion: This report underscores the responsibility of differential diagnosis and early recognition of GCA facilitated by TAUSG in optimizing treatment outcomes as a viable, noninvasive diagnostic tool. (Quintessence Int 2024;55:336-343; doi: 10.3290/j.qi.b4938419).

Usefulness of 18F-FDG PET-CT for assessing large-vessel involvement in patients with suspected giant cell arteritis and negative temporal artery biopsy.

OBJECTIVE: To investigate the usefulness of 18F-FDG PET-CT for assessing large-vessel (LV) involvement in patients with suspected giant cell arteritis (GCA) and a negative temporal artery biopsy (TAB). METHODS: A retrospective review of our hospital databases was conducted to identify patients with suspected GCA and negative TAB who underwent an 18F-FDG PET-CT in an attempt to confirm the diagnosis. The gold standard for GCA diagnosis was clinical confirmation after a follow-up period of at least 12 months. RESULTS: Out of the 127 patients included in the study, 73 were diagnosed with GCA after a detailed review of their medical records. Of the 73 patients finally diagnosed with GCA, 18F-FDG PET-CT was considered positive in 61 cases (83.5%). Among the 54 patients without GCA, 18F-FDG PET-CT was considered positive in only eight cases (14.8%), which included 1 case of Erdheim-Chester disease, 3 cases of IgG4-related disease, 1 case of sarcoidosis, and 3 cases of isolated aortitis. Overall, the diagnostic performance of 18F-FDG PET-CT for assessing LV involvement in patients finally diagnosed with GCA and negative TAB yielded a sensitivity of 83.5%, specificity of 85.1%, and a diagnostic accuracy of 84% with an area under the ROC curve of 0.844 (95% CI: 0.752 to 0.936). The sensitivity was 89% in occult systemic GCA and 100% in extracranial LV-GCA. CONCLUSION: Our study confirms the utility of 18F-FDG PET-CT in patients presenting with suspected GCA and a negative TAB by demonstrating the presence of LV involvement across different subsets of the disease.

Assessment and comparison of probability scores to predict giant cell arteritis.

INTRODUCTION/OBJECTIVES: To assess and compare the performance of the giant cell arteritis probability score (GCAPS), Ing score, Bhavsar-Khalidi score (BK score), color Doppler ultrasound (CDUS) halo count, and halo score, to predict a final diagnosis of giant cell arteritis (GCA). METHOD: A prospective cohort study was conducted from April to December 2021. Patients with suspected new-onset GCA referred to our quaternary CDUS clinic were included. Data required to calculate each clinical and CDUS probability score was systematically collected at the initial visit. Final diagnosis of GCA was confirmed clinically 6 months after the initial visit, by two blinded vasculitis specialists. Diagnostic accuracy and receiver operator characteristic (ROC) curves for each clinical and CDUS prediction scores were assessed. RESULTS: Two hundred patients with suspected new-onset GCA were included: 58 with confirmed GCA and 142 without GCA. All patients with GCA satisfied the 2022 ACR/EULAR classification criteria. A total of 5/15 patients with GCA had a positive temporal artery biopsy. For clinical probability scores, the GCAPS showed the best sensitivity (Se, 0.983), whereas the BK score showed the best specificity (Sp, 0.711). As for CDUS, a halo count of 1 or more was found to have a Se of 0.966 and a Sp of 0.979. Combining concordant results of clinical and CDUS prediction scores showed excellent performance in predicting a final diagnosis of GCA. CONCLUSION: Using a combination of clinical score and CDUS halo count provided an accurate GCA prediction method which should be used in the setting of GCA Fast-Track clinics. Key Points • In this prospective cohort of participants with suspected GCA, 3 clinical prediction tools and 2 ultrasound scores were compared head-to-head to predict a final diagnosis of GCA. • For clinical prediction tools, the giant cell arteritis probability score (GCAPS) had the highest sensitivity, whereas the Bhavsar-Khalidi score (BK score) had the highest specificity. • Ultrasound halo count was both sensitive and specific in predicting GCA. • Combination of a clinical prediction tool such as the GCAPS, with ultrasound halo count, provides an accurate method to predict GCA.

Giant Cell Arteritis after COVID-19 Vaccination with Long-Term Follow-Up: A Case Report and Review of the Literature.

Giant cell arteritis (GCA) is a chronic vasculitis that primarily affects the elderly, and can cause visual impairment, requiring prompt diagnosis and treatment. The global impact of the coronavirus disease 2019 (COVID-19) pandemic has been substantial. Although vaccination programs have been a key defense strategy, concerns have arisen regarding post-vaccination immune-mediated disorders and related risks. We present a case of GCA after COVID-19 vaccination with 2 years of follow-up. A 69-year-old woman experienced fever, headaches, and local muscle pain two days after receiving the COVID-19 vaccine. Elevated inflammatory markers were observed, and positron emission tomography (PET) revealed abnormal uptake in the major arteries, including the aorta and subclavian and iliac arteries. Temporal artery biopsy confirmed the diagnosis of GCA. Treatment consisted of pulse therapy with methylprednisolone, followed by prednisolone (PSL) and tocilizumab. Immediately after the initiation of treatment, the fever and headaches disappeared, and the inflammation markers normalized. The PSL dosage was gradually reduced, and one year later, a PET scan showed that the inflammation had resolved. After two years, the PSL dosage was reduced to 3 mg. Fourteen reported cases of GCA after COVID-19 vaccination was reviewed to reveal a diverse clinical picture and treatment response. The time from onset of symptoms to GCA diagnosis varied from two weeks to four months, highlighting the challenge of early detection. The effectiveness of treatment varied, but was generally effective similarly to that of conventional GCA. This report emphasizes the need for clinical vigilance and encourages further data collection in post-vaccination GCA cases.

Temporal artery biopsy for suspected giant cell arteritis: A mini review.

Giant cell arteritis (GCA) is a granulomatous inflammation involving medium and large vessels that can lead to serious clinical manifestations associated with tissue ischemia. Temporal artery biopsy (TAB) is currently the gold standard method for the diagnosis of GCA, with a specificity of 100% and a sensitivity of 77%. However, the false-negative rate for TAB ranges from 9% to 61%. False negatives may be related to the timing of biopsy, the length of specimen, and the existence of "skip lesions." We reviewed the relevant evidence for methods to improve the sensitivity and reduce the false-negative rate for TAB. To reduce the false-negative rate for TAB, it is recommended to perform TAB within 1 week of starting corticosteroid therapy. Although there is currently no consensus, we suggest that the temporal artery is cut to a length of 20‒30 mm and to prepare serial pathological sections. It is necessary to attach great importance to patients suspected of having GCA, and complete TAB should be performed as soon as possible while starting corticosteroid therapy promptly. We also discuss the clinical value of non-invasive vascular imaging technologies, such as DUS, CTA, MRA, and 18F-FDG-PET/CT, as auxiliary methods for GCA diagnosis that could partially replace TAB.

Transitions in vascular ultrasonography findings of temporal arteritis in a GCA case with progressive temporal headache and visual impairment.

The European League Against Rheumatism and the American College of Rheumatology have stated that the halo sign on vascular ultrasonography (v-US) is relevant in diagnosing giant cell arteritis (GCA) and is equivalent to temporal artery biopsy. However, there are only a few reports about transitions in v-US findings after glucocorticoid (GC) therapy. We report the transitions in the v-US findings in a case of GCA after GC therapy. The patient had rapidly progressive symptoms, and there were concerns about blindness. After GC therapy, we first observed improvement in headache and visual impairment symptoms within 1 week, followed by rapid improvement in laboratory findings within 2 weeks. Subsequently, there were improvements in v-US findings after more than 2 months. In conclusion, these findings showed a dissociation between improvements in clinical symptoms and v-US findings of the temporal artery. Additionally, this case suggests that regular examination of v-US findings is useful in evaluating GCA with evident vascular wall thickness before GC therapy.

Age-related histopathological findings in temporal arteries.

AIMS: Giant cell arteritis (GCA) is a systemic vasculitis affecting medium and large arteries in patients aged over 50 years. Involvement of temporal arteries (TA) can lead to complications such as blindness and stroke. While the diagnostic gold standard is temporal artery biopsy (TAB), comorbidities and age-related changes can make interpretation of such specimens difficult. This study aims to establish a baseline of TA changes in subjects without GCA to facilitate the interpretation of TAB. METHODS AND RESULTS: Bilateral TA specimens were collected from 100 consecutive eligible postmortem examinations. Subjects were divided into four age groups and specimens semiquantitatively evaluated for eccentric intimal fibroplasia, disruption and calcification of the internal elastic lamina (IEL), medial attenuation and degree of lymphocytic inflammation of the peri-adventitia, adventitia, media and intima. The individual scores of intimal fibroplasia, IEL disruption and medial attenuation were added to yield a 'combined score (CS)'. Seventy-eight 78 decedents were included in the final analysis following exclusion of 22 individuals for either lack of clinical information or inability to collect TA tissue. A total of 128 temporal artery specimens (50 bilateral from individual decedents, 28 unilateral) were available for examination. Intimal proliferation, IEL loss, IEL calcification and CS increased with age in a statistically significant fashion. Comparison of the oldest age group with the others showed statistically significant differences, although this was not uniformly preserved in comparison between the three youngest groups. CONCLUSION: Senescent arterial changes and healed GCA exhibit histological similarity and such changes increase proportionally with age. The CS demonstrates significant association with age overall and represents a potential avenue for development to 'normalise' TA biopsies from older individuals.

Giant cell arteritis: An interesting case presentation.

Giant cell arteritis (GCA), otherwise known as temporal arteritis, is a form of large vessel vasculitis. Patients may present with a variety of symptoms but the most common include headaches, jaw claudication, fatigue, night sweats and visual disturbance. Diagnosis is made using a combination of temporal artery ultrasound, clinical findings and blood tests and the diagnostic gold standard of a temporal artery biopsy and is sometimes needed for histopathological confirmation. Syphilis is a sexually transmitted disease caused by the spirochaete Treponema pallidum, which can infect the central nervous system and cause neurosyphilis, which can mimic GCA.

Imaging of giant cell arteritis - recent advances.

Imaging is increasingly being used to guide clinical decision-making in patients with giant cell arteritis (GCA). While ultrasound has been rapidly adopted in fast-track clinics worldwide as an alternative to temporal artery biopsy for the diagnosis of cranial disease, whole-body PET/CT is emerging as a potential gold standard test for establishing large vessel involvement. However, many unanswered questions remain about the optimal approach to imaging in GCA. For example, it is uncertain how best to monitor disease activity, given there is frequent discordance between imaging findings and conventional disease activity measures, and imaging changes typically fail to resolve completely with treatment. This chapter addresses the current body of evidence for the use of imaging modalities in GCA across the spectrum of diagnosis, monitoring disease activity, and long-term surveillance for structural changes of aortic dilatation and aneurysm formation and provides suggestions for future research directions.

Temporal artery biopsy.

Giant cell arteritis is a common vasculitis in patients over the age of 50 years old. If not promptly recognized and aggressively treated with high-dose glucocorticoids, ischemia resulting in permanent vision loss or stroke can occur. Yet, the treatment with high-dose glucocorticoids over a long period of time can be problematic in this particular patient population given their age and associated comorbidities. Temporal artery biopsies (TAB) are an important diagnostic tool to evaluate patients with suspected giant cell arteritis. Herein, we explore indications for TAB and practical points in obtaining a TAB based on available evidence. We review the surgical procedure itself and associated complications. Lastly, we examine common pathological findings and considerations of alternative diagnoses.

Tongue necrosis secondary to giant cell arteritis.

Tongue necrosis is a rare clinical finding because of its rich vascularisation. Giant cell arteritis (GCA) is the most frequent cause of it, and when present, it is usually one side affected. We describe a patient with several months of constitutional syndrome; during that period, she develops headache followed by tongue necrosis, which lead to clinical suspicion of GCA, later confirmed by a temporal artery biopsy. Before the biopsy, she was treated with corticosteroids. We discuss this illness and tongue necrosis as a rare manifestation to consider.

Indication of Activated Senescence Pathways in the Temporal Arteries of Patients With Giant Cell Arteritis.

OBJECTIVE: Giant cell arteritis (GCA) affects almost exclusively individuals above 50 years old, suggesting a role of aging-related changes such as cellular senescence in its pathobiology. The kinases p21(WAF1/CIP1) and p16/INK4A play key roles in 2 distinct pathways leading to senescence. The proinflammatory molecules interleukin-6 (IL-6) and granulocyte-macrophage colony-stimulating factor (GM-CSF), which are key components of the senescence-associated secretory phenotype (SASP), are effective targets of treatment in GCA. Here, we aimed to investigate the presence of p21+ and p16+ cells producing these SASP cytokines in temporal artery biopsies (TABs) of patients with GCA. METHODS: Eight patients with GCA and 14 age-matched, non-GCA individuals who underwent a TAB were included. Immunohistochemical staining of p21, p16, IL-6, and GM-CSF was performed. Multiplex immunofluorescent staining was performed to investigate the colocalization of p21 and p16 with IL-6, GM-CSF, and immune cell markers (CD68, CD3, CD20). RESULTS: We found that expression levels of p16, p21, IL-6, and GM-CSF were elevated in the TABs of patients with GCA. Both p16- and p21-expressing cells were mainly found near the internal lamina elastica, especially among giant cells and macrophages, although p21 and p16 expression could be found in all 3 layers of the vessels. Expression of p16 and p21 was occasionally found in T cells but not B cells. The p16+ and p21+ cells expressing GM-CSF/IL-6 were detected throughout the TABs. CONCLUSION: Our data suggest the presence of activated senescence pathways at the site of vascular inflammation in GCA and support further research into the role of senescence in the pathophysiology of GCA.

Temporal Artery Biopsy: When Is It Worth the Headache?

BACKGROUND: Temporal artery biopsy is ordered when clinical symptoms and an elevated C-reactive protein values and/or erythrocyte sedimentation rates suggest giant cell arteritis. The percentage of temporal artery biopsies positive for giant cell arteritis is low. The objectives of our study were to analyze the diagnostic yield of temporal artery biopsies at an independent academic medical center and to develop a risk stratification model for triaging patients for possible temporal artery biopsy. METHODS: We retrospectively reviewed the electronic health records of all patients who underwent temporal artery biopsy in our institution from January 2010 through February 2020. We compared clinical symptoms and inflammatory marker (C-reactive protein and erythrocyte sedimentation rate) values of patients whose specimens were positive for giant cell arteritis with those of patients with negative specimens. Statistical analysis included descriptive statistics, chi-square test, and multivariable logistic regression. A risk stratification tool, which included point assignments and measures of performance, was developed. RESULTS: Of 497 temporal artery biopsies for giant cell arteritis performed, 66 were positive and 431 were negative. Jaw/tongue claudication, elevated inflammatory marker values, and age were associated with a positive result. Using our risk stratification tool, 3.4% of low-risk patients, 14.5% of medium-risk patients, and 43.9% of high-risk patients were positive for giant cell arteritis. CONCLUSIONS: Jaw/tongue claudication, age, and elevated inflammatory markers were associated with positive biopsy results. Our diagnostic yield was much lower when compared with a benchmark yield determined in a published systematic review. A risk stratification tool was developed based on age and the presence of independent risk factors.