A 35 year-old, sexually active woman presents with fever and right upper abdominal pain for 3 days and pelvic pain for a week. She also vomited twice just prior to admission. The abdominal pain was sharp and exacerbated by inspiration and movement. Her last menstrual period was 2 weeks ago. Her medical history is unremarkable. A complete blood count shows only a leukocytosis of 12,000/mm3 with 80% neutrophils.