[Clinical course of Horton disease. Apropos of 42 cured patients]

We report a prospective study of 42 patients with biopsy-proven giant cell arteritis (CGA) who recovered for more than one year (mean follow up of 71 months since withdrawal of steroid treatment). It was used the same regimen of prednisone and well closely monitored along the whole treatment. In 22 patients, dapsone was given concomitantly with prednisone. Mean duration of steroid therapy was 23.1 months (range: 6-57 months); it was significantly decreased with treatment by dapsone (12 months and 12 days). Age, sex, initial clinical and biological (acute phase reactants) findings did not provide useful information for predicting steroid treatment needed for recovery. Thirty-six relapses were observed in 22 patients (60%) during treatment or after its withdrawal. Incidence of relapses declined during steroid treatment and relapses were (only) observed over first 6 months after steroid withdrawal. Three amaurosis fugax occurred at the beginning of treatment and an axillar bilateral stenosis was also observed. Forty-eight side effects of corticosteroids were recorded in 26 patients (63%): myopathy (n = 12), bone complications (n = 11), metabolic complications (n = 9). Twelve patients (63%) had experienced side effects of dapsone. This study emphasized the difficulty in treating CGA. Close monitoring is required. A steroid regimen is recommended.