Tubo-ovarian abscess (TOA) is mostly a sequela of pelvic inflammatory disease (PID) which is seen in sexually active women. Less commonly, tubo-ovarian abscess can occur because of an infected adjacent organ such as the appendix [1]. Fifteen cases of tubo-ovarian abscess were reported in virgin girls in English literature. The etiology of TOA in most of these patients was uncertain [2,3,4,5,6,7,8,9,10,11,12,13,14] and only one was suspected to be due to appendicitis [15]. Although we assumed that the TOA in our patient is older than the appendicitis, as there was a well-organized abscess with peritoneal covering and without any acute inflammatory findings, appendicitis still remains the only pathology present in our case to explain the etiology of the TOA.
The differential diagnosis of TOA included ovarian cyst, hydrosalpinx, ectopic pregnancy, tumors, pelvic inflammatory disease, and other abscesses of gastrointestinal system such as abscess due to perforated appendicitis [6]. Clinically, symptoms of a tubo-ovarian abscess are identical to appendicitis, especially perforated appendicitis [11]. Both perforated appendicitis and TOA patients have the same clinic presentation such as fever, abdominal tenderness, increased leukocyte count, and increased inflammatory markers. In these patients differential diagnosis can only be achieved by radiological examinations such as USG, computerized tomography (CT) or magnetic resonance imaging (MRI) [1]. With USG, the TOA is presented as a multilocular, thick-walled, dense-content cystic mass with a thick septa in the adnexal region [9], similar to our patient’s radiological findings. In our patient, USG imaging reported a complicated cyst in the right ovary that was presumed as a hemorrhagic cyst of the ovary, but it did not refer to the pathology as TOA. The differential diagnosis in our case was a hemorrhagic cyst of the ovary and laparotomy was done with a prediagnosis of appendicitis as the appendix diameter was measured as 12 mm with USG. As TOA is rare in sexually inactive girls and as the appendix was reported to be thicker than normal in our patient, our diagnosis was in favor of appendicitis. Our patient was considered as a perforated appendicitis and surgical treatment was planned accordingly. In light of our experience, in this case, we came to the conclusion that TOA should also be considered in the differential diagnosis of perforated appendicitis in patients with radiological findings similar to this case, although the patient is not sexually active.
Management of TOA is antibiotic treatment with drainage of the abscess in selected cases [1]. Some cases may need salpingo-oophorectomy [2, 5, 9, 11, 14]. Anaerobic bacterial coverage is recommended for all TOA cases with gram-negative antibacterial treatment [1]. Our broad-spectrum antibiotic treatment and drainage of the abscess during operation were sufficient for both appendicitis and TOA treatment, and 3 months later, the control pelvic USG was normal.
The prognosis of an incidental carcinoid tumor of the appendix is excellent in children [16]. For adults, five-year survival is 92% in patients with a tumor localized only in the appendix, 82% in patients with a tumor with local metastases, and 31% in those with distant metastasis [18]. Some authors reported that in children, the carcinoid tumor of the appendix did not behave aggressively, and an appendectomy alone was sufficient even with tumors >2 cm in size [16]. In our patient, additional surgical treatment was not required since the tumor was less than 2 cm, the mitotic activity was less than 1/10 and the Ki-67 proliferation index was 2%.
Carcinoid tumor of the appendix with tubo-ovarian abscess has not been previously reported. In our patient the TOA was covered with the peritoneum, was conglomerated with the ovary and uterine tube, and was devoid of acute inflammation, suggesting that it may be an older pathology. Due to these findings, we are not sure that appendicitis was the cause of the TOA. The etiology of the TOA also could be previously perforated and healed appendicitis, chronic appendicitis or bacterial translocation via blood to that region. Since the patient was not sexually active, and there was no previous history of pelvic inflammation, the cause of TOA was not considered to be PID. However, the presence of acute appendicitis was the only pathology present in our case to explain the etiology of the TOA.
The limitations of this case report is that we could not be sure about the etiology of the abscess and when it occurred. As we discussed in our findings, the abscess seemed to be present for a long period, but there was no clear history for such an etiology of the abscess, and the only possible etiological pathology was appendicitis. Although we reviewed the possible etiological factors by asking questions to the patient’s family, there could be missing information as the family could have had forgotten. We defined the case as acute appendicitis as the gross appearance of the appendix was very thick, inflammated, and edematous. But at the pathological examination, the pathologists reported only about the carcinoid tumor, and added the detail as ‘Appendectomy material has a length of 4 cm and a diameter of 1 cm. Fibrin and regions of hemorrhage are seen at serosa. Fecaloid was present at lumen.’