Differential Diagnosis for 45 yo with Pain Started at the Umbilicus and then Radiated to Right Lower Abdomen

• Single most likely diagnosis
  • Appendicitis: The classic presentation of appendicitis is pain starting near the umbilicus and then migrating to the right lower quadrant of the abdomen, which matches the patient's symptoms. This condition is common and should be considered first due to its prevalence and the potential for serious complications if not treated promptly.
• Other Likely diagnoses
  • Ovarian cyst or torsion: In women, ovarian cysts or torsion can cause severe lower abdominal pain that may initially be more generalized before localizing. Although the pain typically starts in the lower abdomen, it's conceivable for it to begin around the umbilicus and then radiate.
  • Intestinal obstruction: This condition can cause abdominal pain that may start centrally and then become more localized as the obstruction affects bowel segments differently. The pain pattern can vary but often includes nausea, vomiting, and changes in bowel habits.
  • Kidney stone: While kidney stones typically cause flank pain, it's possible for the pain to radiate to the lower abdomen, especially if the stone is moving down the ureter. However, the pain usually starts in the flank and radiates to the groin.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Ectopic pregnancy: Although less common in a 45-year-old, ectopic pregnancy can occur and is a life-threatening condition. The pain can be variable but often includes lower abdominal pain, sometimes starting centrally.
  • Ruptured abdominal aortic aneurysm: This is a medical emergency that can present with severe abdominal pain, which may initially be diffuse before localizing. It's more common in older adults and those with risk factors for vascular disease.
  • Mesenteric ischemia: This condition involves insufficient blood flow to the intestines and can cause severe abdominal pain that is out of proportion to the physical examination findings. It's a critical diagnosis to consider due to its high mortality rate if not promptly treated.
• Rare diagnoses
  • Meckel's diverticulitis: A complication of a Meckel's diverticulum, which is a congenital anomaly of the small intestine. It can cause abdominal pain similar to appendicitis but is less common.
  • Primary or metastatic tumors of the abdomen: Various tumors can cause abdominal pain, but they are less likely to present with the specific pattern of pain radiating from the umbilicus to the right lower quadrant.