Investigations and treatment
Trans-abdominal ultrasound showed a pelvic thick-walled multilocular complicated cyst containing echogenic debris, measuring 70*6.8*56 cm in the left adnexa. Magnetic resonance image revealed a unilateral complex multilocular thick-walled fluid-filled ovarian mass with an irregular thick uniform enhancing wall and septa at the left side of the pelvic, causing pressure on the adjacent uterus associated with surrounding pelvic fat haziness. The above mentioned lesion in MRI demonstrated heterogeneous intermediate and hyper signal intensity on T2-weighted images, low signal intensity on T1-weighted images, high signal intensity on diffusion-weighted imaging (DWI), and low signal intensity on apparent diffusion coefficient (ADC) indicated restricted diffusion. These observations indicated the presence of tubo-ovarian abscess(Fig. 1) .
Additionally, a high T2 signal intensity track with enhancement was seen between the left anterior wall of the lower rectum and the left posterior wall of the vagina with surrounding fat haziness, in favor of the rectovaginal fistula (Fig. 2) .
Due to persistent fever, abscess drainage was performed under an ultrasound guide. Puncturing of the swollen left ovary revealed internal pus and pus was collected for bacterial culture and the abscess was excised without any substantial compromise to the ovary. The culture was positive for Escherichia coli . Clindamycin 900 mg IV every 12 hours and Gentamicin loading dose IV (2 mg/kg) followed by 1.5 mg/kg every 8 hours was administered.
The rectovaginal fistula was managed conservatively according to the colorectal surgeon’s recommendation. She was discharged after 6 days; the CRP level on the day of discharge was 4.12 mg/dL. Oral Clindamycin at 900 mg/BID was continued for 14 days. Finally, imaging performed one month after the procedure showed no recurrence of ovarian abscess.
Written informed consent was obtained from the patient and her mother for the publication of the report.