Acne fulminans, the most severe form of acne, comprises ulcerative nodulocystic lesions with general, abdominal, and skeletal symptoms acute in onset. In our case, the patient initially had been managed as acute appendicitis. Antibiotic therapy had been administered in full doses with systemic corticosteroids, usually recommended as primary treatment. Few days later, we observed the complete palette of clinical manifestations (vasculitis-like lesions and joint pain) and the classic signs (nodules and pustules on face and chest) allowing the correct diagnosis. Our treatment was peculiar: a systemic antibiotic therapy, based on cephalosporines, proved to be effective.