Kinetics of C-Reactive Protein in Giant Cell Arteritis Following Glucocorticoid Initiation: A Pilot Study (GIDEON)

Giant cell arteritis (GCA) is a chronic systemic vasculitis of the large vessels characterized by a significant inflammatory syndrome, correlated with disease activity and various inflammatory biomarkers, including CRP, which more effectively reflects disease activity.

Relapses remain frequent, with rates of up to 45.7%. Recommended treatments involve long-term corticosteroid therapy and/or sparing therapies, which are associated with adverse events.

Identifying relapsing patients is therefore crucial, in order to best adapt initial treatment and patient follow-up.

We therefore propose to study CRP kinetics at diagnosis and at initiation of corticosteroid therapy, to determine the link with disease progression.

Inclusion criteria

• Adult patients aged 18 or older hospitalized in the internal medicine department with a new diagnosis of ACG
• Personne affiliée ou bénéficiaire d'un régime de sécurité sociale
• Free and informed consent signed by the participant and the investigator

Exclusion criteria

• Patients scheduled to be placed on a sparing regimen during hospitalization
• Patients with renal insufficiency (eGFR ≤ 60 mL/min/1.73 m²)
• Patients with a history of corticosteroid-treated pseudopolyarthritis
• Patients with ACG and visual impairment (severity criterion)
• Patients on immunosuppressants or biologic therapy
• HIV infection or progressive malignancy
• Known poor treatment adherence
• Dementia
• Pregnant or breastfeeding women
• Patients under legal guardianship