RESUMEN
INTRODUCTION: Isotretinoin has been reported to induce inflammatory back pain (IBP) and sacroiliitis in the patients with acne vulgaris. The aim of this study is to investigate the incidence of IBP and sacroiliitis in patients receiving isotretinoin treatment compared with oral antibiotics for acne vulgaris. MATERIALS AND METHODS: A total of 201 patients with moderate-to-severe acne vulgaris who received isotretinoin (n = 100) or oral antibiotics (n = 101) were included in the study. All patients were monthly questioned for IBP symptoms during their treatment. Patients described IBP were also evaluated for sacroiliitis by c-reactive protein, sedimentation rate, HLAB27, and sacroiliac magnetic resonance imaging (MRI). Isotretinoin was discontinued in all patients diagnosed as sacroiliitis, and these patients were reevaluated after 3 months. RESULTS: IBP was observed in 21 (10.4%), and sacroiliitis was detected in 11 (11%) patients on isotretinoin treatment; in oral antibiotic group, we did not observe IBP or sacroiliitis. The incidence of IBP and sacroiliitis differed significantly between the isotretinoin and oral antibiotic groups (p < 0.0001, p = 0.02). Complete regression was observed in the great majority of patients following cessation of isotretinoin. CONCLUSIONS: Our study is the largest prospective controlled study that investigated the incidence of sacroiliitis in patients receiving isotretinoin and compared with patients using oral antibiotics.