Question

A 28-year-old female presents to the emergency department with severe, sudden-onset left lower abdominal pain that started two hours ago. She describes the pain as sharp and constant, radiating to her back. She has no significant medical history except for irregular menstrual cycles. On examination, she appears in distress, with tenderness and guarding in the left lower quadrant. Her vitals show a heart rate of 110 beats per minute, blood pressure of 110/70 mmHg, and a temperature of 37°C. Pelvic examination reveals cervical motion tenderness and adnexal tenderness on the left side. A urine pregnancy test is positive.

Question:

1. What is the most likely diagnosis, and what immediate steps would you take to manage this patient?
2. Discuss the key differential diagnoses for this presentation.
3. What imaging modality would you use to confirm the diagnosis, and why?
4. Describe the management plan if the diagnosis is confirmed.

Answer 1

1. Most Likely Diagnosis and Immediate Management:

   • Most Likely Diagnosis: Ectopic pregnancy, specifically a ruptured ectopic pregnancy, considering the positive pregnancy test, acute abdominal pain, and adnexal tenderness.
   • Immediate Management:
     • Stabilize the patient with IV fluids and blood transfusion if needed.
     • Perform a focused assessment with sonography for trauma (FAST) to assess for intra-abdominal bleeding.
     • Prepare the patient for urgent surgical intervention, usually laparoscopy, to confirm the diagnosis and manage the ectopic pregnancy.

2. Key Differential Diagnoses:

   • Ruptured ovarian cyst
   • Ovarian torsion
   • Acute pelvic inflammatory disease (PID)
   • Appendicitis
   • Endometriosis

3. Imaging Modality:

   • Transvaginal ultrasound is the preferred imaging modality as it provides high sensitivity and specificity for detecting ectopic pregnancies and assessing pelvic structures. It can identify the presence of an adnexal mass, free fluid in the pelvis, and the absence of an intrauterine pregnancy.

4. Management Plan if Diagnosis is Confirmed:

   • Surgical Management: Immediate laparoscopy or laparotomy is indicated in cases of hemodynamic instability or confirmed rupture.
   • Medical Management: In stable, unruptured cases, methotrexate can be considered if criteria are met (e.g., small ectopic size, low β-hCG levels).
   • Post-Operative Care: Monitor for hemodynamic stability, administer Rh immunoglobulin if the patient is Rh-negative, and counsel on future pregnancy risks and contraception.