Tuboovarian abscess

The causes of intraabdominal abscess overlap those of peritonitis and, in fact, may occur sequentially or simultaneously. Appendicitis is the most frequent cause of abscess. Other potential causes of intraabdominal abscess include pancreatitis, diverticulitis, lesions of the biliary tract, genitourinary tract infections, perforating tumors in the abdomen, trauma, and leaking intestinal anastomoses. In addition, pelvic inflammatory disease in women may lead to tuboovarian abscess. For certain diseases, such as appendicitis and diverticulitis, abscesses occur more frequently than generalized peritonitis. 

In the majority of cases, tuboovarian abscesses (TOA) result from pelvic inflammatory disease. It is reported to complicate PID in up to one-third of patients hospitalized for treatment [6]. Other etiologies include complications of surgery or intra-abdominal inflammatory bowel diseases, such as appendicitis, diverticulitis, or Crohn disease. In most cases, TOA is caused by a polymicrobial infection with a high prevalence of anaerobes. lUD users, especially in the first few months after insertion, are also under a higher risk of PID. Pelvic actinomycosis is considered to be highly associated with the use of lUD [1]. 

TOA most commonly occurs in women in the reproductive ages. Tuboovarian abscesses in postmenopausal women are rare, and encountered in patients with diabetes or previous radiation therapy [7]. Because of the significant association with malignancies in postmenopausal women presenting with TOAs, a concomitant pelvic malignancy should be excluded [8]. 

The vast majority of tuboovarian abscesses are multilocular masses with thick walls and necrotic areas. Bowel, uterus, parietal peritoneum, and omentum usually become adherent. The abscess may enlarge and fill the cul-de-sac or leak and produce metastatic abscesses and cause local peritonitis. 

In CT and MRI, tuboovarian abscesses are thick-walled, complexheterogenousfluid-containingadnexalmasses that are found unilaterally or bilaterally (Fig. 17.4) They may contain irregular inner contours, internal septa, gas, fluid, or a fluid-debris level [3]. Necrosis or loculated liquid areas may resemble serous fluid, but also be proteinaceous or hemorrhagic with Tl short-... 

Fig. 17.4a,b. Bilateral tuboovarian abscesses. Consecutive transaxial FS TIWI (a, b) at the level of the acetabulum. Bilateral centrally cystic thick-walled adnexal lesions ) show ill-defined margins toward the surrounding fat. Excessive contrast enhancement along the uterosacral ligaments, rectal wall, mesorectal fat tissue and the left round ligament (arrow) is also noted (b). J , rectum. Courtesy of Dr A. Heuck, Munich... 

Fig. 17.5a,b. Peritonitis in tuboovarian abscess. Transaxial CT sans in the mid pelvis (a, b). A left-sided tuboovarian abscess is located adjacent to the pelvic sidewall (arrow) between internal and external iliac vessels (a). It presents as a cystic peripherally enhancing lesion with a fluid-fluid level (arrowhead) presenting debris (a). Associated flndings include ascites, linear peritoneal enhancement (small arrows), and a netlike involvement of the pelvic fat and the omentum (arrow) (b)... 

Clinically, ruptured ovarian cysts may resemble ovarian torsion. In a patient with acute pelvic pain, a hemorrhagic lesion within a normal size ovary is typically a ruptured ovarian cyst. Furthermore, unlike in most cases of ovarian torsion, clotted blood may be detected in the lesser pelvis. Wall edema of an adnexal mass, engorged adnexal vessels or dilatation of the fallopian tube are missing. TUboovarian abscess and hydrosalpinx may resemble advanced adnexal torsion. Lack of enhancement supports the diagnosis of ovarian torsion. In children, sonography usually allows the diagnosis of appendicitis as a cause of acute pelvic pain. In case of a suspected abscess or an ovarian mass, MRI may aid in further assessment of the adnexa. Rarely, a calcified mass may result from chronic infarction which cannot reliably be differentiated from a calcified ovarian tumor [19]. 

---