Fewer subsequent relapses and lower levels of IL-17 in Takayasu arteritis developed after the age of 40 years

A Glimpse into Humoral Response and Related Therapeutic Approaches of Takayasu's Arteritis

Takayasu's arteritis (TAK) manifests as an insidiously progressive and debilitating form of granulomatous inflammation including the aorta and its major branches. The precise etiology of TAK remains elusive, with current understanding suggesting an autoimmune origin primarily driven by T cells. Notably, a growing body of evidence bears testimony to the widespread effects of B cells on disease pathogenesis and progression. Distinct alterations in peripheral B cell subsets have been described in individuals with TAK. Advancements in technology have facilitated the identification of novel autoantibodies in TAK. Moreover, emerging data suggest that dysregulated signaling cascades downstream of B cell receptor families, including interactions with innate pattern recognition receptors such as toll-like receptors, as well as co-stimulatory molecules like CD40, CD80 and CD86, may result in the selection and proliferation of autoreactive B cell clones in TAK. Additionally, ectopic lymphoid neogenesis within the aortic wall of TAK patients exhibits functional characteristics. In recent decades, therapeutic interventions targeting B cells, notably utilizing the anti-CD20 monoclonal antibody rituximab, have demonstrated efficacy in TAK. Despite the importance of the humoral immune response, a systematic understanding of how autoreactive B cells contribute to the pathogenic process is still lacking. This review provides a comprehensive overview of the biological significance of B cell-mediated autoimmunity in TAK pathogenesis, as well as insights into therapeutic strategies targeting the humoral response. Furthermore, it examines the roles of T-helper and T follicular helper cells in humoral immunity and their potential contributions to disease mechanisms. We believe that further identification of the pathogenic role of autoimmune B cells and the underlying regulation system will lead to deeper personalized management of TAK patients. We believe that further elucidation of the pathogenic role of autoimmune B cells and the underlying regulatory mechanisms holds promise for the development of personalized approaches to managing TAK patients.

Benefits and challenges of 18F-FDG PET/CT in patients with Takayasu arteritis

AIM

To evaluate the diagnostic performance of 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in TA diagnosis and Takayasu arteritis (TA) activity assessment.

MATERIALS AND METHODS

This retrospective study included patients with TA diagnosed according to the American College of Rheumatology (ACR) criteria and undergoing 18F-FDG PET/CT imaging from October 2010 to July 2022. TA activity was assessed through 18F-FDG PET/CT (maximum standard uptake value [SUVmax], vascular SUVmax/mean standard uptake value [SUVmean] of liver (SUV ratio), and PET vascular activity score [PETVAS]) using physician global assessment (PGA) as the reference standard, and the results of these assessments were compared against the clinical activity scores (National Institutes of Health [NIH] and Indian Aortitis Disease Activity [ITAS-A] scores), acute-phase reactants (APR), and white blood cell and platelet counts.

RESULTS

Twenty 18F-FDG PET/CT examinations from 19 patients were included in the study, nine were performed in the active phase and 11 in the inactive phase. The involved vessels showed segmental and tubular FDG uptake in the active group. The average SUVmax, SUV ratio, and PETVAS was 6.3 ± 2.7 (range 3.4-12), 4.2 ± 1.7 (range 2.1-7.5), and 22.7 ± 11.2 (range 6-39), respectively, in the active group and 1.7 ± 0.9 (0.9-3.1), 1.1 ± 0.6 (range 0.6-2.4), and 3.5 ± 5.5 (range 0-18), respectively, in the inactive group. The sensitivity, specificity of SUVmax, SUV ratio, and PETVAS for TA activity assessment were 100%, 100%; 100%, 90.9%; and 88.9, 90.9%, respectively. After ROC curve analysis, a new SUVmax cut-off was obtained. Based on the new cut-off value, SUVmax 3.3 and SUV ratio 1.9 had a more perfect assessment performance.

CONCLUSION

18F-FDG PET/CT is an alternative imaging technique for TA.

Comparative Efficacy of Secukinumab Versus Tumor Necrosis Factor Inhibitors for the Treatment of Takayasu Arteritis

OBJECTIVE

Tumor necrosis factor (TNF) alpha and interleukin-17 (IL-17) are thought to be involved in the pathogenesis of Takayasu arteritis (TAK), and TNF inhibitors (TNFi) are recommended for the treatment of TAK. The present study was undertaken to investigate the efficacy of secukinumab, an IL-17A monoclonal antibody, compared to treatment with TNFi.

METHODS

This was a prospective, single-center, open-label cohort study. Patients with active TAK who did not respond to treatment with glucocorticoids combined with 2 immunosuppressive agents were treated with either secukinumab or TNFi as an add-on therapy without an increased dosage of glucocorticoids. A complete response was defined as complete resolution of signs and symptoms of active disease, normal values of inflammatory markers, no progression on imaging of involved arteries, and dose of glucocorticoid <15 mg/day. A partial response was similarly defined as a complete response except with an erythrocyte sedimentation rate <40 mm/hour and C-reactive protein level of <20 mg/liter.

RESULTS

Nineteen patients in the secukinumab group and 34 patients in the TNFi group were enrolled. The demographic data and inflammatory markers of the 2 groups were comparable at baseline. Complete response and partial response for patients treated with secukinumab and TNFi were 31.6% and 58.8% (P = 0.057), respectively, at 3 months and 52.6% and 64.7%, respectively, at 6 months (P = 0.389).

CONCLUSION

Our findings suggest that secukinumab and TNFi are effective for patients with TAK who do not respond to oral glucocorticoids and conventional immunosuppressive agents, with similar response rates at 3 and 6 months.

New-Onset Ulcerative Colitis in a Young Caucasian Woman with Unclassified Arteritis

Takayasu arteritis is a rare disease mostly found in Asian populations. Cases have been reported in patients with inflammatory bowel disease, suggesting possible genetic linkage. The objective of this clinical case report is to highlight a rare finding of arteritis signs and symptoms in a 32-year-old Caucasian woman (likely early that it did not yet meet classification for official diagnosis as Takayasu arteritis) who subsequently was diagnosed with ulcerative colitis a few months later. The patient presented to the hospital with throbbing neck pain and tenderness around the area of her right carotid artery distribution, nonspecific visual changes, and bilateral upper extremity paresthesia, with significant findings of 50-69% right carotid artery stenosis on a recent outpatient carotid Doppler ultrasound. Based on additional laboratory, clinical, and advanced imaging findings at the hospital, a diagnosis of arteritis not yet classifiable as Takayasu arteritis was made, and the patient was treated with corticosteroids. Unfortunately, she developed bradycardia that was later attributed to the corticosteroid regimen and the medication was discontinued. By follow-up in the clinic, the patient's carotidynia improved, but now, she reported a three-month history of bloody stools. Colonoscopy and pathology findings were consistent with ulcerative colitis, and the patient was started on mesalamine. The association of inflammatory bowel disease and Takayasu arteritis should not be overlooked, as future treatment methods and early, continuous surveillance may be critical in improving quality of life and avoiding serious complications.

Unmet Needs in the Pathogenesis and Treatment of Vasculitides

Despite the progress in the last years on the field of vasculitides, there are several unmet needs regarding classification, disease activity assessment, predictors of flares and complications, and type of treatment for the different forms. The 1990 American College of Rheumatology (ACR) classification criteria currently used to define giant cell arteritis and Takayasu arteritis were designed to discriminate between different types of vasculitides but not to differentiate vasculitis from other disorders. Recently, efforts have been made to overcome the shortcomings of the ACR criteria. The lack of an accepted definition of disease activity in large-vessel vasculitides presents a major challenge in creating useful and valid outcome tools for the assessment of disease course. Identification of predictors of flares can aid in optimizing therapeutic strategies, minimizing disease flares, and reducing treatment-related side effects. It is furthermore important to recognize and characterize the risk factor that might predict the manifestations associated with poor outcome and prognosis. Two RCTs have evidenced the efficacy of tocilizumab in addition to glucocorticoids (GCs) in the treatment of giant cell arteritis (GCA). However, the role of tocilizumab or other biological agents without GCs needs to be investigated. Recent observational studies have suggested that rituximab is also effective in patients with eosinophilic granulomatosis with polyangiitis and in antineutrophil cytoplasmic antibodies (ANCA)-negative patients with granulomatosis with polyangiitis and microscopic polyangiitis. Rituximab or anti-TNF alfa may represent a possible alternative therapy in case of refractory or difficult to treat polyarteritis nodosa (PAN) patients. The new International Criteria for Behçet's Disease have shown a better sensitivity and a better accuracy compared to the older International Study Group on Behçet's Disease criteria. The EULAR recommendations for the management of Behçet's disease (BD) have been recently updated. However, the treatment of refractory disease is still a real challenge.