Objective: To evaluate transvaginal sonographic findings in ambulatory patients with suspected pelvic inflammatory disease (PID).
Methods: We studied 51 outpatients with a mean age of 26.8 years (range 16-52) who had a history of low abdominal pain, negative pregnancy test, and no gynecologic procedures performed during the last month. Endometrial biopsy was used for the histopathologic diagnosis. The presence of plasma cell endometritis was used as the criterion standard for the diagnosis of PID. Sonography was performed before biopsy in a blinded fashion without knowledge of the clinical findings and laboratory results except for the pregnancy test. Repeat pelvic and ultrasound examinations were performed 4 weeks after antimicrobial therapy.
Results: Endometrial biopsy revealed plasma cell endometritis in 13 cases (25%). Thickened fluid-filled tubes were seen in 11 of 13 patients (85%) with plasma cell endometritis and in none of those without. Other sonographic findings associated with plasma cell endometritis were polycystic-like ovaries and free pelvic fluid. A sonogram suggestive of PID, ie, thickened fluid-filled tube with or without free pelvic fluid, had a sensitivity of 85% and a specificity of 100% for the diagnosis of plasma cell endometritis. None of the patients with a normal sonogram or simple cyst had plasma cell endometritis. Repeat examination after 4 weeks showed that the sonographic findings had resolved in 60% of the patients who had had histologic evidence of infection.
Conclusion: Transvaginal sonography can facilitate the outpatient management of patients with suspected PID.