Giant cell arteritis: early diagnosis is key

An in-depth comparison of vascular inflammation on ultrasound, FDG-PET/CT and MRI in patients with suspected giant cell arteritis

BACKGROUND

Giant cell arteritis (GCA) is a difficult to diagnose large vessel vasculitis. CDUS, FDG-PET/CT and MRI are increasingly used for GCA diagnosis. This study aims to assess vascular wall lesions in GCA suspected patients, directly comparing CDUS, FDG-PET/CT and MRI with each other.

METHODS

In a nested-case control study, consecutive GCA suspected patients were included. Scans were retrospectively assessed by two experts per imaging modality. Inter- and intraobserver agreement using Cohen's or Fleiss Kappa were calculated to assess agreement between experts, a few duplicated scans and between imaging modalities. Sensitivity and specificity of the imaging modalities for overall diagnostic performance and for individual arteries were calculated.

RESULTS

In total, 42 patients were included. Overall diagnostic performance of imaging modalities was comparable. Sensitivity and specificity were highest in the temporal artery for CDUS (76% and 93%; Kappa > 0.7) and MRI (60% and 100%; Kappa > 0.7), and in the vertebral (61% and 100%; Kappa 0.56) and maxillary artery (52% and 100%; Kappa 0.75) for FDG-PET/CT. Agreement between all modalities for a positive temporal artery was 0.76, but only 0.28 between CDUS and FDG-PET/CT. Agreement for the axillary artery was 0.7 between CDUS and FDG-PET/CT.

CONCLUSION

The temporal artery can be assessed by CDUS and MRI with good sensitivity and high specificity, and the axillary artery by CDUS and FDG-PET/CT with high agreement between the two modalities. In addition, the vertebral and maxillary artery can be assessed by FDG-PET/CT with good sensitivity and specificity, however the vertebral artery had moderate interobserver agreement.

A direct comparison in diagnostic performance of CDUS, FDG-PET/CT and MRI in patients suspected of giant cell arteritis

OBJECTIVES

This study directly compares the diagnostic performance of colour duplex ultrasound (CDUS), fluor-18-deoxyglucose positron emission tomography computed tomography (FDG-PET/CT) and magnetic resonance imaging (MRI) in patients suspected of giant cell arteritis (GCA).

METHODS

Patients with suspected GCA were included in a nested-case control pilot study. CDUS, whole body FDG-PET/CT and cranial MRI were performed within 5 working days after initial clinical evaluation. Clinical diagnosis after six months follow-up by experienced rheumatologists in the field of GCA, blinded for imaging, was used as reference standard. Diagnostic performance of the imaging modalities was determined. Stratification for GCA subtype was performed and imaging results were evaluated in different risk stratification groups.

RESULTS

In total, 23 patients with GCA and 19 patients suspected of but not diagnosed with GCA were included. Sensitivity was 69.6% (95%CI 50.4%-88.8%) for CDUS, 52.2% (95%CI 31.4%-73.0%) for FDG-PET/CT and 56.5% (95%CI 35.8%-77.2%) for MRI. Specificity was 100% for CDUS, FDG-PET/CT and MRI. FDG-PET/CT was negative for GCA in all isolated cranial GCA patients (n = 8), while MRI was negative in all isolated extracranial GCA patients (n = 4). In four GCA patients with false-negative (n = 2; intermediate and high risk) or inconclusive (n = 2; low and intermediate risk) CDUS results, further imaging confirmed diagnosis.

CONCLUSIONS

Sensitivity of CDUS was highest, while specificity was excellent in all imaging modalities. Nevertheless, confidence intervals of all imaging modalities were overlapping. Following EULAR recommendations, CDUS can be used as a first test to diagnose GCA. With insufficient evidence for GCA, further testing considering GCA subtype is warranted.

Utilising multiple discharge coding will improve identification of patients with giant cell arteritis: a retrospective analysis of a hospital discharge dataset

To determine whether the discharge diagnosis codes used within tertiary hospitals accurately identified patients with Giant Cell Arteritis (GCA), as determined by expert opinion at 6 months. The study was performed across three major hospitals within Perth, Western Australia. Patients with an International Classification of Diseases (ICD) code for GCA (M31.5 and M31.6) at discharge on first inpatient presentation were identified. Review of case notes, discharge summaries, letters, pathology, and imaging results were undertaken. The percentage of patients with an ICD code for GCA at initial discharge with confirmed GCA by expert opinion at 6 months (as the anchor diagnosis) was calculated. As validation of the anchor diagnosis, the percentage who fulfilled the 2022 ACR/EULAR criteria was also calculated, the number of hospital discharges per patient with an ICD code for GCA was calculated, to determine if multiple discharges with an ICD code for GCA increased the specificity of the ICD coding. 93 out of 157 admissions with an ICD for GCA were identified as a first inpatient presentation. At 6 months follow up, 65.6%, 95 CI [55.0%, 75.1%] had confirmed GCA by expert opinion. 88.2%, 95 CI [79.8%, 93.9%] met the 2022 ACR/EULAR criteria for GCA. The specificity of the ICD coding increased with increasing number of discharges- 67.4% with single episode, 80% with two episodes, and 100% with three or more episodes (p = 0.1373). Only 43.8%, 95 CI [26.4%, 62.3%] of patients who did not have GCA had an alternative diagnosis provided. 31.3%, 95 CI [16.1%, 50.0%] of patients who did not have GCA still have the GCA diagnosis listed in their subsequent clinical records and discharge summaries. Only 2/3rds of those patients with an initial discharge ICD code for GCA were found to have confirmed GCA at follow-up. This poor correlation between the ICD coding and confirmed diagnosis of GCA will impact the quality of data extracted from administrative health datasets for epidemiological and longitudinal studies. Selecting patients with two or more GCA coded episodes could improve the homogeneity of the cohort for recruitment into GCA studies, but a larger sample size study is required.

A Machine Learning Model Based on Radiomic Features as a Tool to Identify Active Giant Cell Arteritis on [18F]FDG-PET Images During Follow-Up

Objective: To investigate the feasibility of a machine learning (ML) model based on radiomic features to identify active giant cell arteritis (GCA) in the aorta and differentiate it from atherosclerosis in follow-up [18F]FDG-PET/CT images for therapy monitoring. Methods: To train the ML model, 64 [18F]FDG-PET scans of 34 patients with proven GCA and 34 control subjects with type 2 diabetes mellitus were retrospectively included. The aorta was delineated into the ascending, arch, descending, and abdominal aorta. From each segment, 95 features were extracted. All segments were randomly split into a training/validation (n = 192; 80%) and test set (n = 46; 20%). In total, 441 ML models were trained, using combinations of seven feature selection methods, seven classifiers, and nine different numbers of features. The performance was assessed by area under the curve (AUC). The best performing ML model was compared to the clinical report of nuclear medicine physicians in 19 follow-up scans (7 active GCA, 12 inactive GCA). For explainability, an occlusion map was created to illustrate the important regions of the aorta for the decision of the ML model. Results: The ten-feature model with ANOVA as the feature selector and random forest classifier demonstrated the highest performance (AUC = 0.92 ± 0.01). Compared with the clinical report, this model showed a higher PPV (0.83 vs. 0.80), NPV (0.85 vs. 0.79), and accuracy (0.84 vs. 0.79) in the detection of active GCA in follow-up scans. Conclusions: The current radiomics ML model was able to identify active GCA and differentiate GCA from atherosclerosis in follow-up [18F]FDG-PET/CT scans. This demonstrates the potential of the ML model as a monitoring tool in challenging [18F]FDG-PET scans of GCA patients.

Investigating interferon type I responses in patients with suspected giant cell arteritis and polymyalgia rheumatica

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are closely related inflammatory disorders. Easily measurable biomarkers defining active disease and identifying patients in need of glucocorticoid sparing treatment options are highly desired. Interferon Type I (IFN-I) might be involved in disease pathology; however, evidence is limited. This study explores a systemic IFN-I signature and expression of IFN-I markers in GCA and PMR patients. Treatment naive GCA and PMR patients, and PMR patients with glucocorticoid treatment were included. Patients suspected of but not diagnosed with GCA were used as controls. Five relevant IFN-I-stimulated genes were identified in literature, and relative expression levels were determined using quantitative reverse transcription polymerase chain reaction (RT-qPCR) in peripheral blood mononuclear cells. An IFN-I score was generated. Serum levels of IFN-I induced C-X-C motif chemokine 10 (CXCL10) and Galectin-9 were determined by multiplex immunoassay. There were no differences in IFN-I scores between the groups. An IFN-I signature was observed in 0/9 controls, 2/11 GCA patients, 4/20 treatment naive PMR patients, and 2/10 PMR patients with treatment. Serum CXCL10 and Galectin-9 were not increased in GCA or PMR patients compared to control patients. Treated PMR patients had lower CXCL10 levels [423.2 pg/ml (375.1-491.1)] compared to treatment naive PMR patients [641.8 pg/ml (552.8-830.6)]. An IFN-I signature does not distinguish GCA and PMR patients from controls. Also, IFN-I-induced serum markers are not upregulated in GCA and PMR patients. Easily measurable IFN-I-induced serum markers will therefore probably not aid in diagnosis and additional treatment options in newly diagnosed GCA and PMR patients.

Silent Inflammation: A Case of Blurry Vision Raising Diagnostic Challenges in an Elderly Patient

Giant cell arteritis (GCA) is a large vessel vasculitis with cranial and extracranial vessel involvement. Clinicians suspect GCA when a patient exhibits symptoms or exam findings of temporal headache with sudden vision loss, jaw or tongue claudication, scalp tenderness, abnormal temporal artery exam, and diagnostic findings, including elevated inflammatory markers. We present a case, which highlights that, despite established diagnostic measures, challenges persist. The unexpected presentation serves as a valuable reminder of the condition's diverse manifestations.

Utility of online GCA risk models in predicting the result of temporal artery biopsy within a clinical setting: study of diagnostic and screening tests

BACKGROUND

Temporal artery biopsy (TAB) is the gold standard for the diagnosis of giant cell arteritis (GCA) but has many limitations. The Ing model, González-López model, and Weis model are tools to estimate a patient's likelihood of GCA. This study investigates the utility of these prediction models in triaging patients referred for TAB.

METHODS

This study is a retrospective examination of patients who underwent TAB by a neuro-ophthalmologist over a 5-year period. Data collected through chart review were inputted into prediction models to evaluate GCA risk and compared with TAB results and clinical diagnosis. Cut-off values for 100% sensitivity and specificity for TAB result were used to determine whether TAB could be avoided where there was preoperative certainty of the result.

RESULTS

Among 155 eligible patients, mean age was 73 years, and 78.1% were female. TAB was negative in 103 patients (66.5%) and positive in 42 patients (27.1%). Twenty-three patients (22.3%) were diagnosed clinically and treated for biopsy-negative GCA. The Ing model had no positive biopsies below 10.59% and no negative biopsies above 68.44%. The González-López model had no positive biopsies below 0.27% and no negative biopsies above 98.08%. The Weis model had no positive biopsies with a score less than zero.

CONCLUSION

Forty-one biopsies (28.9%) could have been avoided using the Ing model, 9 (6.34%) using the González-López model, and 28 (19.7%) using the Weis model. The findings suggest that the Ing and Weis models are useful screening tools for GCA with the potential to improve the effective use of health care resources.

Diagnostic delay in patients with giant cell arteritis: results of a fast-track clinic

Giant cell arteritis (GCA) can lead to severe complications if left untreated. The aim of this study was to describe time from onset of symptoms to diagnosis and treatment in GCA suspected patients in a fast-track clinic (FTC), and secondarily to assess the influence of GCA symptoms on this time. A retrospective cohort consisting of suspected GCA patients who visited the FTC between January 2017 and October 2019 was used. Time between symptom onset, first general practitioner visit, FTC referral, first FTC visit, and treatment initiation was analysed. Furthermore, this was stratified for subtypes of GCA and GCA symptoms. Of 205 patients referred with suspected GCA, 61 patients received a final diagnosis of GCA (GCA+) and 144 patients had no GCA (GCA-). Median time after onset of symptoms to first FTC visit was 31.0 days (IQR 13.0-108.8) in all referred patients. Time between onset of symptoms and first GP visit was 10.5 (4.0-36.3) days, and time between first GP visit and FTC referral was 10.0 (1.0-47.5) days. Patients were generally seen at the FTC within 1 day after referral. For patients with isolated cranial GCA (n = 41), median delay from onset of symptoms to treatment initiation was 21.0 days (11.0-73.5), while this was 57.0 days (33.0-105.0) in patients with extracranial large-vessel involvement (n = 20) (p = 0.02). Our results indicate considerable delay between symptom onset and FTC referral in patients suspected of GCA. Suspected patients were examined and GCA+ patients were treated instantly after referral. Key Points • GCA can cause severe complications with delayed treatment, but non-specific symptoms make diagnosis challenging. • Diagnostic delay still occurs despite introducing a successful fast-track clinic resulting from delay between start of symptoms and FTC referral. • Patients who presented with constitutional symptoms had longer delay than patients who presented with isolated cranial symptoms.

Comparing Diagnostic Performance of Short and Long [18F]FDG-PET Acquisition Times in Giant Cell Arteritis

(1) Background: In giant cell arteritis (GCA), the assessment of cranial arteries using [18F]fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) combined with low-dose computed tomography (CT) may be challenging due to low image quality. This study aimed to investigate the effect of prolonged acquisition time on the diagnostic performance of [18F]FDG PET/CT in GCA. (2) Methods: Patients with suspected GCA underwent [18F]FDG-PET imaging with a short acquisition time (SAT) and long acquisition time (LAT). Two nuclear medicine physicians (NMPs) reported the presence or absence of GCA according to the overall image impression (gestalt) and total vascular score (TVS) of the cranial arteries. Inter-observer agreement and intra-observer agreement were assessed. (3) Results: In total, 38 patients were included, of whom 20 were diagnosed with GCA and 18 were without it. Sensitivity and specificity for GCA on SAT scans were 80% and 72%, respectively, for the first NMP, and 55% and 89% for the second NMP. On the LAT scans, these values were 65% and 83%, and 75% and 83%, respectively. When using the TVS, LAT scans showed especially increased specificity (94% for both NMPs). Observer agreement was higher on the LAT scans compared with that on the SAT scan. (4) Conclusions: LAT combined with the use of the TVS may decrease the number of false-positive assessments of [18F]FDG PET/CT. Additionally, LAT and TVS may increase both inter and intra-observer agreement.

External validation of the 2022 ACR/EULAR classification criteria in patients with suspected giant cell arteritis in a Dutch fast-track clinic

OBJECTIVE

Recently the Diagnostic and Classification Criteria in Vasculitis Study group developed and published new American College of Rheumatology/EULAR classification criteria for giant cell arteritis (GCA). To test robustness in a different clinical setting and inform clinicians on performance in clinical practice, we aim to externally validate them in patients with a suspicion of GCA referred to our GCA fast-track clinic.

METHODS

Patients with suspected GCA from the Hospital Group Twente Early GCA in Twente prospective cohort were included. The clinical diagnosis of GCA verified after 6 months of follow-up made by the treating rheumatologist was used as a reference standard. A cut-off score of ≥6 was tested as described in the original article. Area under the receiver operating characteristics curve, sensitivity and specificity were calculated.

RESULTS

In total, 133 patients with suspected GCA were included, of whom 53 were diagnosed with GCA and 80 patients were not diagnosed with GCA. The area under the curve (AUC) was 0.96 (95% CI 0.92 to 0.98). Using the proposed cut-off score of≥6, we found that sensitivity was 98.0% (95% CI 89.9% to 100%) and specificity was 57.5% (95% CI 45.9% to 68.5%). The majority of misclassified patients without GCA had classification scores of 6 and 7 as clinical and/or laboratory criteria were often present in our non-GCA population.

CONCLUSION

Our results showed an excellent AUC and sensitivity with a moderate specificity for classification of GCA patients. Considering our relevant study population, we found that the new classification criteria might also be useful for diagnostic purposes, albeit with careful interpretation.

Temporal Artery Ultrasound for the Diagnosis of Giant Cell Arteritis in the Emergency Department

Giant cell arteritis (GCA), known as temporal arteritis, is a serious condition requiring immediate treatment to prevent complications. GCA can be difficult to diagnose, especially in emergency department (ED) settings where ophthalmology and rheumatology services may be unavailable. Temporal artery ultrasound (TAUS) is a valuable tool for diagnosing GCA. In the ED, TAUS can be used to quickly rule out GCA and avoid unindicated steroid treatment, which can cause serious morbidity in elderly patients. This article discusses the use of TAUS for evaluating patients with suspected GCA in the ED and its potential to expedite treatment and ensure appropriate, timely follow-up for patients with this potential vision and life-threatening condition.

Evidence for increased interferon type I activity in CD8+ T cells in giant cell arteritis patients

Introduction

Giant cell arteritis (GCA) is a vasculitis of the medium- and large-sized arteries. Interferon type I (IFN-I) is increasingly recognized as a key player in autoimmune diseases and might be involved in GCA pathogenesis, however evidence is limited. IFN-I activates Janus kinase/signal transducers and activators of transcription (JAK-STAT) pathways, leading to increased expression of interferon stimulated genes. In this study, IFN-I activity in GCA is explored, focusing on CD8+ T cells.

Methods

Expression of phospho-STAT (pSTAT) 1, 3 and 5 was investigated in IFN-α-stimulated peripheral mononuclear cells (PBMCs) gated separately for CD8+ T cells of patients with GCA (n=18), healthy controls (HC, n=15) and infection controls (n=11) by Phosphoflow method combined with fluorescent cell barcoding technique. Furthermore, IFN-I induced myxovirus-resistance protein A (MxA) and CD8+ T cell expression was investigated by immunohistochemistry in temporal artery biopsies (TAB) of GCA patients (n=20) and mimics (n=20), and in aorta tissue of GCA (n=8) and atherosclerosis patients (n=14).

Results

pSTAT1 expression was increased in IFN-α stimulated CD8+ T cells from GCA patients, whereas no difference was observed in pSTAT3 and pSTAT5 expression. MxA was present in TABs of 13/20 GCA patients compared to 2/20 mimics and in 8/8 GCA+ compared to 13/14 GCA- aorta tissues. MxA location partially co-localized with CD8+T cells.

Conclusions

Our results provide evidence for increased IFN-I activity in CD8+ T cells of GCA patients, both systemically and locally. These findings warrant further investigation regarding IFN-I induced biomarkers and IFN-I related novel therapeutic options in GCA.

Optic perineuritis

PURPOSE OF REVIEW

This review paper aims at discussing pathogenesis, etiology, clinical features, management, and prognosis of OPN.

RECENT FINDINGS

Optic perineuritis (OPN) is an inflammatory process primarily involving the optic nerve sheath. Clinically, OPN usually presents with unilateral, gradual decline of visual function, eye pain, and/or pain on eye movements, disc edema and various features of optic nerve dysfunction, including visual field defects. It can mimic typical optic neuritis. In most cases of OPN, the disease is isolated with no specific etiology being identified, however, it can also occur secondary to a wide range of underlying systemic diseases. OPN is clinically diagnosed and radiologically confirmed based on the finding of circumferential perineural enhancement of the optic nerve sheath on magnetic resonance imaging (MRI).

SUMMARY

Unlike optic nerve, OPN is not typically self-limited without treatment. High-dose oral corticosteroids are the mainstay of treatment in OPN. The initiation of therapy usually causes rapid and dramatic improvement in signs and symptoms. In general, OPN usually has a relatively good visual prognosis, which is influenced by delays between the onset of visual loss and the initiation of steroid therapy as well as the presence of underlying systemic diseases.

A Case Report of Post COVID19 Giant Cell Arteritis and Polymyalgia Rheumatica With Visual Loss

COVID-19 shares some features of giant-cell arteritis, in which the diagnosis needs a high suspicion for prompt investigation and therapy. When the diseases coexist this might lead to diagnosis delay with grave consequences. We reported a case of a post-COVID-19 giant cell arteritis and polymyalgia rheumatica with visual loss. We treated the patient with pulse methylprednisolone 1 gm daily for 3 consecutive days followed by 60 mg prednisolone for 4 weeks until normalization of ESR, and then, gradual withdrawal. Oral Paracetamol, vitamin-D3, and calcium carbonate were added to the treatment regimen. The headache continued, so, we started perineural injection therapy (PIT) once daily, for 6 sessions, at which the headache was completely resolved after the third injection. The vision was regained completely after the sixth injection.

Large-Vessel Vasculitis in Ophthalmology: Giant Cell Arteritis and Takayasu Arteritis

ABSTRACT

Giant cell arteritis and Takayasu arteritis are large-vessel vasculitides that share multiple common features but also have significant differences in epidemiology, demographics, clinical presentation, evaluation, and treatment. Giant cell arteritis is more common in elderly patients of Caucasian descent versus Takayasu arteritis, which is more prevalent in younger patients of Asian descent. Although traditionally age has been the main criterion for differentiating the 2 etiologies, modifications in the diagnostic criteria have recognized the overlap between the 2 conditions. In this monograph, we review the diagnostic criteria for both conditions and describe the epidemiology, pathogenesis, histology, evaluation, and management for large-vessel vasculitis in ophthalmology. Additionally, we describe ocular imaging techniques that may be utilized by ophthalmologists to identify manifestations of large-vessel vasculiti- des in patients. Lastly, we compare and contrast the key clinical, laboratory, and pathologic features that might help ophthalmologists to differentiate the 2 entities.

Arteritic Anterior Ischemic Optic Neuropathy in the Course of Giant Cell Arteritis After COVID-19

BACKGROUND Giant cell arteritis (GCA) is an inflammation of large vessels that affects the lining of the arteries and leads to vessel swelling and the eventual reduction of blood flow. This can result in ischemia of the optic nerve, which is known as arteritic anterior ischemic optic neuropathy (AAION). The present case seems noteworthy because the patient developed GCA with the ocular manifestation of AAION shortly after having COVID-19. CASE REPORT A 69-year-old woman was admitted to the Clinic of Ophthalmology after having COVID-19. She reported vision loss in the left eye, which appeared 2.5 weeks after a positive SARS-CoV-2 test. While in the hospital, she was diagnosed with AAION and GCA. The patient was treated with enoxaparin sodium, prednisone, and methotrexate. Three months after the hospitalization, the visual acuity of the left eye was limited to light perception, and optic nerve atrophy was reported. CONCLUSIONS We would like to emphasize the role of SARS-CoV-2 infection as a possible risk factor for the onset of GCA and its ocular manifestations, such as AAION. However, further research is needed to determine the relationship between SARS-CoV-2 infection and GCA. Because some symptoms of the 2 diseases are similar, the diagnosing process might be long and challenging. The diagnosis of GCA should be made as soon as possible to avoid serious complications, such as bilateral vision loss.

Giant cell arteritis complicated by tongue necrosis and bilateral cerebellar ischaemic stroke

Giant cell arteritis (GCA) typically presents with headache, scalp tenderness or visual disturbance. Other symptoms include orofacial pain, constitutional symptoms and ischaemic stroke. An 81-year-old woman with a background of type-2 diabetes and hypertension presented with headache, oral pain and right visual loss. Examination showed hypertension, nodular temporal arteries, reduced visual acuity and suspected oral candida. Inflammatory markers were raised and she was diagnosed with GCA and commenced on corticosteroids. During treatment she developed tongue ulceration, then acute vertigo and incoordination with nystagmus and ataxia. Neuroimaging confirmed bilateral, cerebellar ischaemic strokes and temporal artery biopsy was consistent with GCA. With corticosteroids and secondary prevention of stroke measures she is now functionally independent. Oral pain is an uncommon symptom of GCA and delays in recognition may lead to catastrophic consequences. Clinicians should be aware of uncommon presentations and to optimise additional ischaemic stroke risk-factors.

Acute Neurologic Manifestations of Systemic Immune-Mediated Diseases

Systemic autoimmune diseases can affect the peripheral and central nervous system. In this review, we outline the common inpatient consultations for patients with neurological symptoms from rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus, sarcoidosis, immunoglobulin G4-related disease, Behçet's disease, giant cell arteritis, granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis, polyarteritis nodosa, and ankylosing spondylitis. We discuss the symptoms, diagnostic strategies, and treatment options.

Developments in distinguishing secondary vascular headache from primary headache disorders in clinical practice

INTRODUCTION

Vascular headaches are secondary headache disorders with potentially devastating consequences if missed. Clinicians often struggle to distinguish these from primary headache disorders whereby there is no underlying structural pathology. Here, the authors describe the advancement in our understanding of vascular headache disorders, their clinical presentation and the developments in neuroimaging that facilitate diagnosis.

AREAS COVERED

Here the authors discuss the definition of primary and secondary headache disorders. They review the literature on the presentation, choice of neuroimaging and diagnostic tools that can be used to diagnose specific vascular headaches including Carotid or Vertebral artery dissection, Stroke, Temporal Arteritis, subarachnoid hemorrhage, cerebral venous thrombosis, Reversible Cerebral Vasoconstriction syndrome, Primary angiitis, AV malformation and Genetic vasculopathy. The authors discuss the influence of Covid-19 on the management of patients with headache.

EXPERT OPINION

Whilst developments in neuroimaging have been of paramount importance in the diagnosis of vascular headache disorders, there is no substitute for meticulous history taking and examination. Research has aided our understanding of clinical presentation, however further studies are needed as well as increased education of neurologists and acute physicians.

Optic Perineuritis Distinguishing Arteritic Ischaemic from Amiodarone-Associated Optic Neuropathy

Giant cell arteritis (GCA) is a common medium to large vessel vasculitis of the elderly that can lead to permanent vision loss. Neuroimaging in GCA may reveal optic nerve sheath enhancement, which is a cardinal finding of optic perineuritis (OPN). The clinical manifestations of GCA can mimic that of other ocular disorders including amiodarone-associated optic neuropathy (AAON). We report a case of biopsy-proven GCA in a patient initially suspected to have AAON. This patient presented with bilateral optic disc oedema in conjunction with subacute predominately monocular vision loss and enhancement of the corresponding optic nerve sheath on neuroimaging. Clinicians should recognise that clinical and neuroimaging findings of GCA can mimic a variety of ocular and orbital pathologies including idiopathic OPN and AAON.

Role of temporal artery resection in Horton's arteritis (Review)

Horton's arteritis is found in the literature under various names, such as temporal arteritis, Horton's disease senile arteritis, granulomatous arteritis or giant cell arteritis (GCA). The pathogenic mechanism is the result of an inflammatory cascade triggered by a still unknown factor that causes dendritic cells in vessels to recruit T cells and macrophages, which form granulomatous infiltrates. The clinical picture consists of a daily headache with temporal localization, with moderate to severe intensity, unilateral or bilateral, with a history of months, years. Other changes may include pain in the cheek or tongue during chewing (claudication), weight loss, generalized fatigue, low-grade fever, and frequent pain in the limbs, in the context of coexisting rheumatic polymyalgia. Visual symptoms represent a special category, involving blurred vision, scotomas, and even sudden blindness. Histopathological examination of the temporal artery biopsy reveals focal thickening of the intima, with interruption of the lamina propria, with transmural inflammatory infiltrates, sometimes with multinucleated giant cells. In this article, we aim to review the role of temporal artery resection in the diagnosis of Horton's arteritis, but we also discuss the hypothesis of a potential therapeutic benefit of this procedure. However, there are also clinical situations in which there has been a considerable improvement in clinical symptoms and especially in vision deficit, with the improvement of the visual field after surgery performed for biopsy. It is difficult to estimate the influence of temporal artery resection alone, given that most patients also have concomitant cortisone treatment. However, in some cases, the rapid improvement of symptoms immediately after surgery, with the improvement of visual acuity and visual field, along with the disappearance of the headaches, can create the premises for future studies on a therapeutic contribution of temporal artery resection in GCA.

A Tale of Diagnostic Delay with Detrimental Consequences: Illustrating the Challenging Nature of Diagnosing Giant Cell Arteritis

Giant cell arteritis is a medical emergency as severe, irreversible complications may occur if it is not treated in a timely manner. However, in daily practice early diagnosis can be challenging. We report the case of a 70-year-old woman who presented with multiple ischaemic cerebral vascular accidents related to newly diagnosed giant cell arteritis. Review of her charts revealed a substantial delay from the onset of symptoms to diagnosis. This case demonstrates the need for additional efforts to reduce delay in referring patients with giant cell arteritis and the need to implement fast-track clinics to prevent serious complications.

LEARNING POINTS

Giant cell arteritis is a medical emergency and unnecessary diagnostic delay can result in severe complications.Despite implementation of fast-track clinics, diagnostic delay still occurs due to the generic nature of signs and symptoms and inadequate case finding.As diagnostic delay can lead to preventable complications, increased knowledge and awareness of the characteristics and urgency of giant cell arteritis is needed among referring physicians.

Comparison of 18- and 22-MHz probes for the ultrasonographic diagnosis of giant cell arteritis

PURPOSE

Little is known about the diagnostic concordance of images provided by ultrasound probes with emitting frequencies below or above 20 MHz for the diagnosis of giant cell arteritis (GCA).

METHODS

We compared, using Cohen's kappa statistic, data obtained with an 18-MHz and a 22-MHz probe for the ultrasonographic evaluation of temporal arteries in 80 patients referred for suspected GCA.

RESULTS

The halo sign was found in 25% of cases with the 18-MHz probe and in 35% with the 22-MHz probe. The compression sign was positive in 42% of cases with the 18-MHz probe and 48% with the 22-MHz probe. GCA was finally diagnosed in 20 patients (25%). The kappa coefficient of agreement was 0.76 (P < .001) for the halo sign, and 0.75 (P < .001) for the compression sign.

CONCLUSIONS

Images obtained by 18 MHz and 22-MHz frequency probes showed a good level of agreement for the diagnosis of GCA, but the 22-MHz probe yielded a correct diagnosis of GCA in 3 of the 7 patients in whom examination with the 18-MHz probe was negative.

Acute Stroke due to Vertebral Artery Dissection in Giant Cell Arteritis

The diagnosis of giant cell arteritis (GCA) when presenting with atypical features such as stroke is very challenging. Only 0.17% of first-ever strokes are caused by GCA, a life-threatening condition when left untreated. Very few cases have been reported on giant cell arteritis leading to acute stroke due to vertebral artery dissection. We present a case of a 76-year-old female with no medical history who presented with sudden onset right visual loss and left hemiparesis. She had been initially treated for acute stroke and upon further workup was found to have left vertebral artery dissection. She had erythrocyte sedimentation rate (ESR) of 71 mm/h, and bilateral temporal artery biopsy was consistent with giant cell arteritis. Patient received high doses of methylprednisolone which resolved her hemiparesis, but her vision loss did not improve. Stroke in the presence of significant involvement of vertebral arteries should raise suspicion of GCA especially if classic symptoms preceded stroke event. High clinical suspicion is required to prevent delay in diagnosis and treatment.

Stroke secondary to giant-cell arteritis: A literature review

Stroke is a leading cause of death and disability worldwide. In addition to the classical etiologies of stroke as atherosclerosis and cardioembolism there are many unusual, rare causes, which require a high level of clinical suspicion and further investigations for correct and early diagnosis and adequate treatment. Giant-cell arteritis or temporal arteritis, the most frequent vasculitis in the elderly population is one of the uncommon causes of stroke. In the setting of giant-cell arteritis, stroke more likely affects the vertebrobasilar territory and is the main cause of mortality. Duplex ultrasound examination is a routine investigation for stroke patients and may be key to the diagnosis if the classical hypoechoic ‘halo sign’ is recognized at the level of vertebral arteries. In this situation the ultrasound evaluation of temporal arteries and temporal artery biopsy are mandatory. The Giant-cell arteritis-related stroke is a rare condition; therefore, there are no evidence-based guidelines or standard recommendations for the treatment. In the present review, the main characteristics of giant-cell arteritis-related stroke are discussed.

Corticosteroid Usage in Giant Cell Arteritis

Giant cell arteritis (GCA) is a condition that can cause irreversible visual loss if untreated. While corticosteroids remain the mainstay of treatment to prevent visual loss, the type, dose, route, and duration of corticosteroid treatment of GCA remain controversial. Our study surveyed neuro-ophthalmologists to determine commonly prescribed dosages of corticosteroids for the treatment of GCA with or without visual loss. For patients with acute visual loss, 52% would use intravenous (IV), 46% would use IV or oral and 2% would use oral corticosteroids. Seventy-three per cent would use 500 to 1000 mg IV methylprednisolone in this group. For patients with GCA without acute visual loss, 67% would use the oral route, 30% would use IV or oral, and 3% indicated they would use IV route of treatment. Seventy-five per cent would use 1.0 to 1.5 mg/kg oral prednisone in this group. Our results suggest a majority but not a complete consensus for route and dose of corticosteroid treatment in GCA and confirm conventional recommendations for high dose IV corticosteroids for GCA with visual loss and lower dose oral regimens for GCA without visual loss.

A meta-analysis of the epidemiology of giant cell arteritis across time and space

INTRODUCTION

Giant cell arteritis (GCA) is a common large vessel vasculitis in those over age 50 years. This meta-analysis examined the geographical and temporal distribution of the incidence, prevalence, and mortality of GCA.

METHODS

A systematic review was conducted using EMBASE, Scopus, and PubMed from their inceptions until 2019. Studies were included if they reported at least 50 or more GCA patients and defined the location and time frame. Articles on mortality were included and standardized mortality ratio (SMR) was extracted where possible. Mean pooled prevalence, incidence, and SMR were calculated using a random effects model. Linear regression was used to explore correlations between latitude and incidence, prevalence, and mortality.

RESULTS

Of the 3569 citations identified, 107 were included. The pooled incidence of GCA was 10.00 [9.22, 10.78] cases per 100,000 people over 50 years old. This incidence was highest in Scandinavia 21.57 [18.90, 24.23], followed by North and South America 10.89 [8.78, 13.00], Europe 7.26 [6.05, 8.47], and Oceania 7.85 [- 1.48, 17.19]. Pooled prevalence was 51.74 [42.04, 61.43] cases per 100,000 people over age 50. Annual mortality was 20.44 [17.84, 23.03] deaths/1000. Mortality generally decreased over the years of publication (p = 0.0008). Latitude correlated significantly with incidence (p = 0.0011), but not with prevalence, or mortality.

CONCLUSIONS

GCA incidence varies nearly 3-fold between regions and is highest in Scandinavia but not significantly. Mortality may be improving over time.

Temporal Artery Ultrasound to Diagnose Giant Cell Arteritis: A Practical Guide

The diagnostic modalities for giant cell arteritis (GCA) have evolved significantly in recent years. Among the different diagnostic tools developed, Doppler ultrasound of the temporal arteries, with a sensitivity and specificity reaching 69% and 82%, respectively, is now recognized as superior and, therefore, is a first-line diagnostic tool in GCA. Moreover, with the increasing development of new ultrasound technologies, the accuracy of Doppler ultrasound in GCA seems to be constantly improving. In this article, we describe in detail the scanning technique to perform while realizing Doppler ultrasound of temporal arteries to assess GCA, as well as the diagnostic performance of this tool according to current literature.

An interesting case of temporal arteritis that manifested as ptosis and diplopia

Giant cell arteritis (GCA) or temporal arteritis is a granulomatous vasculitis that affects medium-to-large vessels seen primarily in older Caucasian populations. Here, we describe a 67-year-old male who presented with atypical symptoms of worsening headaches associated with left-sided pupil-sparing, isolated third nerve palsy, blurry vision, diplopia and myalgias in bilateral extremities. He was immediately started on intravenous Methylprednisolone for suspected GCA. Subsequent biopsy of the temporal arteries showed panarteritis without giant cells and disruption of the internal elastic lamina. His symptoms improved in a day following treatment and he was discharged on a Prednisone taper. At the time of writing this case, there are only two cases in the literature of ptosis as a presenting symptom in GCA, thus highlighting the importance of recognizing rare red flag symptoms such as ptosis and diplopia. More study is needed in the prognostic significance of these unusual clinical features.

Pancytopenia as a Complication of Low-Dose Methotrexate in a Septuagenarian: A Rare Presentation

Methotrexate (MTX) is an antimetabolite that was initially developed as a chemotherapeutic agent to treat malignancies but later used extensively to treat rheumatological conditions. MTX-induced toxicity is dose- and duration-dependent. Myelosuppression is a rare but fatal complication of MTX that can occur even with low doses used for inflammatory conditions. Multiple factors such as age, renal impairment, and nutritional status increase the risk of developing MTX toxicity. Frequent monitoring of symptoms and lab values are the hallmarks of prompt diagnosis and prevention of complications. Clinicians should have a high degree of suspicion to diagnose pancytopenia secondary to MTX especially in patients with multiple confounding comorbidities. We present the case of a 79-year-old male who presented with mucositis and pancytopenia diagnosed to be secondary to weekly MTX for giant cell arteritis leading to anemia and septic shock causing death.

Ophthalmic Emergencies for the Clinician

Primary care physicians are at the forefront of patient care and often are the first clinicians to triage and diagnose any eye-related complaints. They must be able to quickly identify vision-threatening pathologies, as delay in treatment of an ocular emergency can result in permanent vision loss. This concise review describes the definition, presentation, examination, and management of various ophthalmic emergencies including blunt ocular trauma, chemical ocular injury, orbital cellulitis, endophthalmitis, acute angle closure glaucoma, optic neuritis, giant cell arteritis, central retinal artery occlusion, retinal detachment, and homonymous hemianopia in a succinct manner.

Training in and comfort with diagnosis and management of ophthalmic emergencies among emergency medicine physicians in the United States

Background/objectives

Patients with ophthalmic emergencies often present to emergency rooms. Emergency medicine (EM) physicians should feel comfortable encountering these conditions. We assessed EM physicians’ comfort working up, diagnosing, and managing ophthalmic emergencies.

Subjects/methods

329 EM physicians participated in this cross-sectional multicentre survey. Questions inquired about the amount, type, and self-perceived adequacy of ophthalmic training. Likert scales were used to assess confidence and comfort working up, diagnosing, and managing ophthalmic emergencies.

Results

Participants recall receiving a median of 5 and 10 h of ophthalmic training in medical school and residency, respectively. Few feel this prepared them for residency (16.5%) or practice (52.0%). Only 50.6% feel confident with their ophthalmic exam. Most (75.0%) feel confident in their ability to identify an ophthalmic emergency, but 58.8% feel well prepared to work them up. Responders feel more comfortable diagnosing acute retrobulbar hematoma (72.5%), retinal detachment (69.8%), and acute angle closure glaucoma (78.0%) than central retinal artery occlusion (28.9%) or giant cell arteritis (53.2%). Only 60.2% feel comfortable determining if canthotomy and cantholysis is necessary in the setting of acute retrobulbar hematoma, and 40.3% feel comfortable performing the procedure. There was a trend towards attending physicians and providers in urban and academic settings feeling more comfortable diagnosing and managing ophthalmic emergencies compared to trainees, non-urban, and non-academic physicians.

Conclusions

Many participants do not feel comfortable using ophthalmic equipment, performing an eye exam, making vision or potentially life-saving diagnoses, or performing vision-saving procedures, suggesting the need to increase ophthalmic training in EM curricula.