Differential Diagnosis for Pelvic Pain in a 21-year-old Woman
Single most likely diagnosis
- Pelvic Inflammatory Disease (PID): This is the most likely diagnosis given the patient's symptoms of bilateral pelvic pain, fever, vaginal discharge, and mild dysuria, along with uterine, adnexal, and cervical motion tenderness on examination. PID is a common condition in sexually active young women, caused by bacterial infection of the upper genital tract.
Other Likely diagnoses
- Endometriosis: Although endometriosis typically presents with cyclic pelvic pain, it can cause chronic pain and should be considered, especially if the patient's pain is not entirely explained by PID.
- Ovarian Cysts: Ruptured or torsed ovarian cysts can cause severe pelvic pain and may be associated with some of the patient's symptoms, although fever and discharge are less common.
- Urinary Tract Infection (UTI): While the patient's symptoms of dysuria and fever could suggest a UTI, the presence of pelvic organ tenderness and vaginal discharge points more towards a gynecological cause.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Ectopic Pregnancy: Although less likely given the gradual onset of symptoms, ectopic pregnancy is a life-threatening condition that must be ruled out in any woman of childbearing age presenting with pelvic pain.
- Appendicitis: Appendicitis can sometimes present with pelvic pain and should be considered, especially if the patient has abdominal tenderness or guarding.
- Ovarian Torsion: This is a surgical emergency that can cause severe pelvic pain and should be considered if the patient's pain is severe and acute.
Rare diagnoses
- Tubo-ovarian abscess: A complication of PID, this would present with more severe symptoms and is less likely given the patient's current presentation.
- Malignancy: Although rare in young women, pelvic malignancies such as ovarian or cervical cancer could cause pelvic pain and should be considered if other diagnoses are ruled out and symptoms persist.