Differential Diagnosis
- Single most likely diagnosis
- Endometrioma: This is the most likely diagnosis given the patient's symptoms of pelvic pain, constant pelvic pressure exacerbated by exercise and sexual activity, and the presence of a unilocular mass with homogeneous, low-level echoes on the left ovary on ultrasound. Endometriomas are often associated with endometriosis, which can cause chronic pelvic pain and infertility.
- Other Likely diagnoses
- Ovarian cyst: The patient's ultrasound shows a unilocular mass on the left ovary, which could be a simple ovarian cyst. However, the presence of pelvic pain and tenderness suggests that the cyst may be related to a more complex condition such as endometriosis.
- Pelvic inflammatory disease (PID): Although the patient's pelvic examination does not show any abnormal cervical discharge, her history of trichomoniasis and pelvic pain raises the possibility of PID. However, the absence of fever and other symptoms makes this diagnosis less likely.
- Do Not Miss
- Ovarian torsion: Although the patient's symptoms have been present for 8 months, ovarian torsion is a medical emergency that requires prompt attention. The presence of a mass on the ovary and pelvic pain raises the possibility of ovarian torsion, especially if the patient's symptoms suddenly worsen.
- Ectopic pregnancy: Although the patient's last menstrual period was 2 weeks ago and she is not currently pregnant, ectopic pregnancy is a life-threatening condition that must be ruled out in any woman of childbearing age with pelvic pain.
- Rare diagnoses
- Dermoid cyst: The patient's ultrasound shows a unilocular mass with homogeneous, low-level echoes, which could be consistent with a dermoid cyst. However, dermoid cysts are relatively rare and often contain heterogeneous elements such as hair, teeth, or fat.
- Tubo-ovarian abscess: The patient's history of trichomoniasis and pelvic pain raises the possibility of a tubo-ovarian abscess, although this diagnosis is less likely given the absence of fever and other symptoms.