Clinical phenotype and complications of large vessel giant cell arteritis: A systematic review and meta-analysis

Recommendations of the French Society of Rheumatology for the management in current practice of patients with polymyalgia rheumatica

OBJECTIVE

To develop recommendations for the routine management of patients with polymyalgia rheumatica (PMR).

METHODS

Following standard procedures, a systematic review of the literature by five supervised junior rheumatologists, based on the questions selected by the steering committee (5 senior rheumatologists), was used as the basis for working meetings, followed by a one-day plenary meeting with the working group (15 members), leading to the development of the wording and determination of the strength of the recommendations and the level of agreement of the experts.

RESULTS

Five general principles and 19 recommendations were drawn up. Three recommendations relate to diagnosis and the use of imaging, and five to the assessment of the disease, its activity and comorbidities. Non-pharmacological therapies are the subject of one recommendation. Three recommendations concern initial treatment based on general corticosteroid therapy, five concern the reduction of corticosteroid therapy and follow-up, and two concern corticosteroid dependence and steroid-sparing treatments (anti-IL-6).

CONCLUSION

These recommendations take account of current data on PMR, with the aim of reducing exposure to corticosteroid therapy and its side effects in a fragile population. They are intended to be practical, to help practitioners in the day-to-day management of patients with PMR.

Large vessel giant cell arteritis

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

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.

Performance of the new 2022 ACR/EULAR classification criteria for giant cell arteritis in clinical practice in relation to its clinical phenotypes

BACKGROUND

To examine the performance of the new 2022 American College of Rheumatology (ACR)/EULAR classification criteria for giant cell arteritis (GCA) in routine clinical care, compared with the 1990 ACR GCA classification criteria.

METHODS

The fulfilment of 2022 ACR/EULAR and 1990 ACR criteria was tested in our real-life cohort of GCA patients with proven vasculitis by temporal artery biopsy or imaging (a necessary pre-requisite to apply the new criteria is the presence of a confirmed diagnosis of medium- or large-vessel vasculitis). The performance of classification criteria was evaluated in all patients with GCA across different subsets of the disease. Patients with GCA were compared with unselected controls with suspected GCA.

RESULTS

A total of 136 patients with proven GCA were identified. The new criteria had a sensitivity of 92.6% and a specificity of 85.2%. According to the clinical phenotypes, the sensitivity was 98.8% in cranial GCA, 92% in extracranial large vessel (LV) GCA and 75% in occult systemic GCA. These data are much better than those observed with the 1990 ACR classification criteria, which showed a sensitivity of 66.1% and a specificity of 85.1% for the total sample, with a sensitivity of 89.1% in cranial GCA, 24% in extracranial LV-GCA and 35.7% in occult systemic GCA. Ten (7.4%) patients in our cohort did not fulfil either of the criteria sets (8 with occult systemic GCA and 2 with extracranial LV-GCA). The sensitivity of the new criteria in patients with occult systemic and extracranial LV-GCA could be greatly improved assigning more weight (3 points) to some imaging findings (axillary involvement and FDG-PET activity throughout the aorta).

CONCLUSION

Our study confirms that the new classification criteria are more sensitive in real-life settings than the old ACR criteria across all clinical phenotypes.