Cases

***** ANSWER *****

Tuboovarian abscess (TOA): The patient's sonograms (Images 1-2) demonstrate an 8 X 6 X 5-cm, multiloculated, complex mass in the left adnexa, which suggests TOA. This condition usually occurs after recurrent, chronic, or refractory pelvic inflammatory disease (PID), but it can also occur during an initial episode of PID. (In some case series, as many as one third of patients with PID developed TOA). Risk factors include a history of sexually transmitted disease, multiple sexual partners, and use of an intrauterine device (IUD) to prevent pregnancy.

The clinical picture of TOA is one of pelvic pain, vomiting, tender adnexal mass, fever, and tachycardia. Abscesses are often bilateral. Typical organisms that cause the infection include Chlamydia trachomatis, an intracellular bacterial pathogen and the predominant STD-related organism that causes PID or TOA, and Neisseria gonorrhea, though its role as the primary cause of PID or TOA has decreased in the United States. Most infections are polymicrobial and include additional organisms, such as Peptococcus species, Streptococcus agalactiae, enteric gram-negative organisms (eg, Escherichia coli), and anaerobic organisms (eg, Bacteroides fragilis).

The differential diagnosis for lower abdominal pain in young women is broad, and caution is recommended in ruling out other infectious and inflammatory conditions, such as appendicitis, periappendiceal abscess, and diverticulitis.

Ultrasonography is the diagnostic imaging modality of choice because of its lack of ionizing radiation, noninvasive nature, and accuracy of diagnosis. Transvaginal sonography allows for detailed visualization of the uterus and adnexa, including the ovaries. Transabdominal sonography is not required, but it can be a useful complementary study to endovaginal examination, as it provides a global view of the pelvic contents. For patients who refuse transvaginal sonography, limited transabdominal study may be performed. 81%, positive predictive value [PPV] = 43%); for this purpose, RaVR was better than a QRS interval of 0.010 s (sensitivity = 82%, PPV = 35%).

Other studies to consider are CT, which has the notable advantage of improving the accuracy of diagnosing appendiceal pathology, which may mimic PID or TOA. In suspected cases of TOA with equivocal sonographic findings, MRI is an excellent imaging modality. Recent findings have suggested that MRI is as effective or even more accurate than other studies in the diagnosis of TOA and PIDs.

Treatment consists of broad-spectrum antibiotic therapy that covers anaerobic organisms. Several regimens, such as cefotetan or cefoxitin + doxycycline or clindamycin + gentamicin, have been suggested. Most cases of TOA (60-80%) resolve with antibiotics alone. In cases that do not respond, laparoscopy may be required to identify and drain any contained pus loculations. A few cases require open laparotomy for rare complications, such as abscess rupture, acute hemorrhage (due to erosion of adjacent blood vessels), and sepsis. Long-term fertility is substantially reduced, even after TOA resolves.

For more information on TOA, see the eMedicine articles Pelvic Inflammatory Disease/Tubo-ovarian Abscess (within the Radiology specialty), Pelvic Inflammatory Disease (within the Emergency Medicine specialty), and Gynecologic Pain (within the Internal Medicine specialty).