Sigmoid colon translocation of an intrauterine device misdiagnosed as a colonic polyp

RATIONALE: Intrauterine contraceptive devices (IUDs) are recommended as a means of contraception. Translocation of IUD is a rare and serious complication. Colonic inflammatory mass caused by translocated IUD initially misdiagnosed as a colonic polyp is extremely rare and has not been reported yet. PATIENT CONCERNS: This report presents a case of sigmoid colon translocation of intrauterine device on a 37-year-old female patient. Colonoscopy was performed due to her complain of repeated blood in stools and subsequently the patient was misdiagnosed as a sigmoid colon polyp. Nonetheless, the "polyp" was not able to be removed endoscopically. DIAGNOSES: Sigmoid colon translocation of an intrauterine device. INTERVENTIONS: To further clarify the diagnosis, computed tomography (CT) scan was performed and the "polyp" was confirmed to be caused by a translocated IUD. OUTCOMES: The translocated IUD was removed easily by surgery, and the patient recovered soon after the operation. LESSONS: The present case indicates that an annual gynaecologic examination is necessary to determine the position of the IUD, and a CT examination may help confirm an ectopic IUD.