RÉSUMÉ
Actinomycosis is a rare entity which presents some difficulties in establishing a correct preoperative diagnosis. Many actinomycotic pelvic infections in women are related to IUD use and the colonization rate appears to increase in accordance with the duration of IUD use. So, all women in IUD use are recommended to make cervicovaginal smear and pelvic infection associated with IUD use should be suspected to have actinomycoses. We report a case which presented painful mass on right upper and lower quadrant of abdomen of a 40-year-old women. We identified sulfur granules by histopathologic exam of surgically resected specimen. Eventually it proved to be pelvic and abdominal actinomycosis associated with the use of an intrauterine device. Because variable clinical pictures and infrequency of the disease make the diagnosis more difficult, increased alertness of clinicians and microbiologists to the presence of anaerobic organism as the cause of infection are needed to make an earlier and more correct diagnosis of actinomycoses and to further avoid any inappropriate treatment.