Differential Diagnosis for 33-year-old Female with Left Flank Pain and Lower Abdominal Pain with Some Vomiting

• Single Most Likely Diagnosis
  • Nephrolithiasis (Kidney Stones): This condition is a common cause of flank pain, often accompanied by nausea, vomiting, and sometimes lower abdominal pain if the stone is moving down the ureter. The pain can be severe and colicky.
• Other Likely Diagnoses
  • Pyelonephritis: An infection of the kidney, which can cause flank pain, fever, nausea, and vomiting. It's more common in women and can be associated with lower abdominal pain if the infection involves the lower urinary tract.
  • Ovarian Cyst or Torsion: Ovarian cysts can cause lower abdominal pain and, if large enough or if they rupture, can also cause flank pain. Ovarian torsion is a more severe condition that requires immediate attention and can present with sudden onset of severe pain.
  • Diverticulitis: Inflammation of a diverticulum in the colon, which can cause lower abdominal pain, sometimes radiating to the flank, and may be accompanied by nausea and vomiting.
• Do Not Miss Diagnoses
  • Ectopic Pregnancy: Although less likely in a patient not suspected to be pregnant, ectopic pregnancy is a life-threatening condition that can present with lower abdominal pain and sometimes flank pain due to bleeding. It's crucial to consider in any female of childbearing age with abdominal pain.
  • Appendicitis: While typically presenting with right lower quadrant pain, appendicitis can occasionally present with pain in other areas, including the left flank or lower abdomen, especially if the appendix is retrocecal.
  • Ruptured Aneurysm or Aortic Dissection: These are rare but life-threatening conditions that can cause severe flank or abdominal pain and require immediate medical attention.
• Rare Diagnoses
  • Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodic hypertension, sweating, palpitations, and flank pain due to catecholamine release.
  • Retroperitoneal Fibrosis: A rare condition characterized by the proliferation of fibrous tissue in the retroperitoneum, which can encase and obstruct structures such as the ureters, leading to flank pain.
  • Primary or Metastatic Tumors of the Kidney, Adrenal Gland, or Other Retroperitoneal Structures: These can cause flank pain and are important to consider, especially in patients with risk factors for cancer.