Presentation
Lower abdominal pain for 5 days with associated nausea, anorexia and constipation. Suprapubic tenderness on examination.
Patient Data
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Transabdominal and transvaginal pelvic ultrasound images showing a normal appearing anteverted, anti-flexed uterus. Endometrial stripe measures 4mm. Both ovaries are identified. The left ovary has a normal appearance. The right adnexae contains a complex, predominantly cystic mass which has an US appearance most in keeping with a tubo-ovarian abscess. An ectopic pregnancy can not be completely excluded. There is a small amount of free pelvic fluid identified.
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Insinuation of the complex mass into anatomical spaces is more in keeping with a tubo-ovarian abscess. No fetal parts to support an ectopic preganancy but could not entirely exclude an cystic ovarian mass.
Acknowledgement: Prof Brian Tress.
Case Discussion
An interesting case highlighting the difficulty in differential diagnosis between a tubo-ovarian abscess, cystic ovarian tumor, and ectopic pregnancy. Whilst likely showing a right tubo-ovarian abscess, in the clinical context a cystic ovarian tumor is considered less likely and an ectopic pregnancy cannot be excluded. Correlation of imaging findings with the beta HCG was recommended in discussions with the treating clinician.
A CT abdo/pelvis with contrast 6 days later showed insinuation of the complex mass into anatomical spaces more in keeping with a tubo-ovarian abscess, did not show any fetal parts to support an ectopic pregnancy but could not entirely exclude a cystic ovarian neoplasm.
A repeat US 1 month later found the cystic mass within the right adnexa to have increased in size with ultrasound appearance in keeping with hydrosalpinx or tubo ovarian abscess.