Gastrointestinal tuberculosis (TB) is rare, but its incidence is increasing in industrialized countries because of the growing numbers of individuals at risk for TB. Herein, we report the exceptional case of a young, HIV-negative, African refugee who presented with acute perforation of an isolated duodenal tuberculous ulcer. Clinical patterns of duodenal TB are discussed. The difficulty of obtaining a diagnosis on the basis of clinical features, endoscopy, and imaging is emphasized, as well as the importance of obtaining a biopsy specimen and its limitations.