Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 57 6 2019 11 17 402 404 EN Hamidreza Najari Department of Infectious Diseases, Qazvin University of Medical Sciences, Qazvin, Iran. Shokrollah Hosseinzadeh Department of Infectious Diseases, Qazvin University of Medical Sciences, Qazvin, Iran. Abbas Allami Department of Infectious Diseases, Qazvin University of Medical Sciences, Qazvin, Iran. 2018 12 08 2019 09 08 As dissemination of Tuberculosis (TB) to soft tissue is not a usual finding, sometimes it is not considered for differential diagnosis and, if so, is overlooked by most health care professionals. Although rare, TB should be considered in the differential diagnosis of cysts of the thigh, especially in endemic areas. We report the case of an 80-year-old female presented with cyst with purulent discharge in her lateral left thigh that was persistent to other surgical and antibiotic treatments. Polymerase chain reaction (PCR) showed positive results for TB. Anti-tubercular therapy had promising results. Our case serves to highlight the importance of considering a reactivated TB infection in individuals with chronic discharge, especially if symptoms are not classic or fail to respond to conventional therapy. Histological study and MRI are useful tools to guide diagnosis, with confirmation provided by PCR. https://acta.tums.ac.ir/index.php/acta/article/view/7622 https://acta.tums.ac.ir/index.php/acta/article/download/7622/5282