Differential Diagnosis for Left Lower Quadrant Pain Radiating to Left Groin

• Single most likely diagnosis
  • Diverticulitis: This condition is a common cause of left lower quadrant pain, especially in older adults. The pain can radiate to the left groin due to the proximity of the sigmoid colon to the groin area.
• Other Likely diagnoses
  • Kidney stones (nephrolithiasis): Stones in the left ureter can cause severe pain that radiates from the flank to the groin.
  • Ovarian cyst or torsion: In females, ovarian cysts or torsion can cause lower abdominal pain that radiates to the groin.
  • Inguinal hernia: An inguinal hernia can cause pain in the groin that radiates to the lower abdomen.
  • Prostatitis or epididymitis: In males, inflammation of the prostate or epididymis can cause pain in the groin and lower abdomen.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Ectopic pregnancy: Although less common, an ectopic pregnancy can cause severe abdominal pain that radiates to the groin and can be life-threatening if not promptly diagnosed.
  • Appendicitis (if the appendix is located in the left lower quadrant): Although appendicitis typically presents with right lower quadrant pain, it can occur in the left lower quadrant if the appendix is malrotated.
  • Ruptured abdominal aortic aneurysm: A ruptured AAA can cause severe abdominal pain that radiates to the groin and back, and is a medical emergency.
• Rare diagnoses
  • Lymphoma: Abdominal lymphoma can cause pain in the lower abdomen that radiates to the groin.
  • Psoas abscess: An abscess in the psoas muscle can cause pain in the lower back and groin.
  • Retroperitoneal fibrosis: A rare condition that causes inflammation and scarring in the retroperitoneum, which can cause abdominal and groin pain.