Differential Diagnosis for Right Lower Quadrant Pain

The following is a list of potential diagnoses for right lower quadrant pain, categorized by likelihood and potential impact.

• Single Most Likely Diagnosis

  • Appendicitis: The most common cause of right lower quadrant pain, especially if it is acute in onset and accompanied by fever, nausea, and vomiting. The pain often starts near the navel and then moves to the right lower quadrant.

• Other Likely Diagnoses

  • Ovarian Cyst or Torsion: Common in women, especially if there is a history of similar pain or known ovarian cysts. The pain can be severe and is often accompanied by nausea and vomiting.
  • Ectopic Pregnancy: Should be considered in women of childbearing age, particularly if there is a missed period or positive pregnancy test. The pain can be severe and is often accompanied by vaginal bleeding.
  • Diverticulitis: More common in older adults, characterized by inflammation of the diverticula in the colon, which can cause pain, fever, and changes in bowel habits.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis can cause chronic or recurrent abdominal pain, often accompanied by changes in bowel habits, weight loss, and fever.

• Do Not Miss Diagnoses

  • Ruptured Ectopic Pregnancy: A life-threatening condition that requires immediate surgical intervention. Symptoms include severe abdominal pain, vaginal bleeding, and signs of shock.
  • Ruptured Appendix: If appendicitis is not treated promptly, the appendix can rupture, leading to peritonitis, which is a life-threatening condition.
  • Ovarian Torsion: Requires immediate surgical intervention to preserve the ovary and prevent complications.
  • Intestinal Obstruction: Can lead to severe complications, including bowel ischemia and perforation, if not promptly diagnosed and treated.

• Rare Diagnoses

  • Mesenteric Lymphadenitis: Inflammation of the lymph nodes in the mesentery, which can mimic appendicitis but is often related to viral infections.
  • Meckel's Diverticulitis: Inflammation of a congenital anomaly of the small intestine, which can cause pain and bleeding.
  • Right Lower Quadrant Pain due to Kidney Stones: While kidney stones more commonly cause flank pain, they can occasionally cause pain that radiates to the right lower quadrant.
  • Hernias: Incarcerated or strangulated hernias can cause severe pain and are surgical emergencies.