A 23-year-old female patient presents to the clinic with a chief complaint of sudden onset of pelvic pain. The pain started earlier today and is localized to the lower abdomen and pelvis. The patient reports that the pain may be radiating to her back and legs, and she has also experienced some nausea and diarrhea.

Significant Positives & Negatives For Differentials

Pelvic Pain

Positives:

• Sudden onset of pelvic pain
• Pain localized to lower abdomen or pelvis
• Pain may radiate to back or legs
• Associated with nausea, vomiting, or diarrhea
• History of recent sexual activity or pelvic infection

Negatives:

• Pain is not localized to the pelvis
• Pain is not associated with other gynecological symptoms
• No history of recent sexual activity or pelvic infection

Urinary Tract Infection (UTI)

Positives:

• Burning or pain with urination
• Increased frequency or urgency of urination
• Suprapubic discomfort or pain
• History of recurrent UTIs

Negatives:

• No urinary symptoms
• No history of recurrent UTIs

Ovarian Cyst

Positives:

• Sudden onset of pelvic pain
• Pain may be unilateral and radiating
• History of ovarian cysts or polycystic ovarian syndrome
• Palpable mass on bimanual exam

Negatives:

• Pain is not localized to the pelvis
• No palpable mass on exam
• No history of ovarian cysts or polycystic ovarian syndrome

Endometriosis

Positives:

• Chronic pelvic pain, often worsening with menstrual cycle
• Pain may be associated with dysmenorrhea, dyspareunia, or dyschezia
• History of infertility or previous endometriosis diagnosis

Negatives:

• Acute onset of pain
• Pain is not associated with menstrual cycle
• No history of infertility or previous endometriosis diagnosis

Pelvic Inflammatory Disease (PID)

Positives:

• Sudden onset of pelvic pain
• Pain may be associated with fever, chills, or vaginal discharge
• History of recent sexual activity or sexually transmitted infection

Negatives:

• No fever, chills, or vaginal discharge
• No history of recent sexual activity or sexually transmitted infection

Based on the information provided, the most likely diagnosis is pelvic pain. The key features that support this are the sudden onset of pelvic pain, with potential radiation to the back or legs, and the association with gastrointestinal symptoms like nausea or diarrhea. However, further investigation would be needed to determine the underlying cause, as the case does not provide enough details to narrow down the differential diagnosis.