Pelvic Actinomycosis Mimicking a Locally Advanced Pelvic Malignancy--case Report.

We present the case of a former user of an intrauterine contraceptive device (IUD) for 10 years, diagnosed with a bulky, fixed pelvic tumor involving the internal genital organs and the recto sigmoid, causing luminal narrowing of the rectum, interpreted as locally advanced pelvic malignancy, probably of genital origin. Intraoperatively, a high index of suspicion made us collect a sample from the fibrous wall of the tumor mass, large Actinomyces colonies were thus identified. Surgery consisted in debridement, removal of a small amount of pus and appendectomy, thus avoiding a mutilating and useless surgery. Specific antibiotic therapy was administered for 3 months, with favorable postoperative and long-term outcomes. Pelvic actinomycosis should always be considered in the differential diagnosis of pelvic tumors in women using an IUD. The association of long-term antibiotic treatment is essential to eradicate the infection and prevent relapses.