Solution: Pelvic inflammatory disease is a serious complication of sexually transmitted diseases. It can include endometritis, salpingitis, salpingo-oophoritis, tubo-ovarian abscess, pelvic peritonitis and Fitz-Hugh-Curtis Syndrome (perihepatitis). In this case, there is a complex cystic process in the right adnexa, which on the US images has a pretty convincing tubular configuration. On the CT, there is impressive inflammatory change and enhancement of the septations. Complications can include ectopic pregnancy, infertility and chronic abdominal pain. The Centers for Disease Control and Prevention (CDC) criteria for the diagnosis of PID are as follows : Minimum criteria (1 or more): -Lower abdominal tenderness -Adnexal tenderness -Tenderness with cervical motion. Additional criteria: Patients with PID should have 1 or more of the following: -Signs of lower genital tract inflammation -Oral temperature higher than 101ºF -Abnormal cervical and vaginal discharge -Greatly increased numbers of white blood cells on saline microscopy of vaginal secretions -Elevated erythrocyte sedimentation rate -Elevated C-reactive protein level -Laboratory documentation of cervical infection with C trachomatis or N gonorrhoeae. Elaborate criteria (additional findings include the following): -Histopathologic evidence of endometritis at endometrial biopsy -Thickened fluid-filled tubes with or without free pelvic fluid or a tubo-ovarian complex on transvaginal sonograms or images from other modalities -Laparoscopic abnormalities that are consistent with PID *Workowski KA, Berman SM. Sexually transmitted diseases treatment guidelines, 2006. MMWR Recomm Rep. Aug 4 2006;55(RR-11):1-94.