Infections are associated with morbimortality of patients with giant cell arteritis (GCA). The aim of this work was twofold: the identification of factors predisposing to the risk of infection and the description of patients hospitalized with an infection occurring during the treatment period of CAG. A monocentric retrospective study was conducted in GCA patients, comparing patients hospitalized for infection with patients without infection. The analysis included 21/144 (14.6%) patients with 26 infections (cases) and 42 control matched on sex, age, and diagnosis of GCA. Both groups were similar except for a higher frequency of seritis in cases (15% vs. 0%, p=0.03). Relapses of GCA were less common in cases (23.8% vs 50.0%, p=0.041). Hypogammaglobulinemia was present during infection. More than half of the infections (53.8%) occurred in the first year of follow-up with an average dose of 15mg/day of corticosteroids. Infections were mainly pulmonary (46.2%) and cutaneous (26.9%). Factors associated with infectious risk were identified. This preliminary monocentric work will continue with a national multicentre study.