Differential Diagnosis for Flank Pain
- Single most likely diagnosis
- Nephrolithiasis (kidney stones): This is often the most common cause of flank pain, typically presenting with severe, sharp pain that may radiate to the groin, accompanied by nausea, vomiting, and sometimes hematuria.
- Other Likely diagnoses
- Pyelonephritis: An infection of the kidney, which can cause flank pain, fever, and other urinary symptoms.
- Musculoskeletal strain: Overuse or injury to the muscles in the flank area can lead to pain.
- Urinary tract infection (UTI): While more commonly associated with lower urinary tract symptoms, UTIs can cause flank pain if the infection ascends to the kidneys.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Renal infarction: A blockage of the blood supply to the kidney, which is a medical emergency.
- Sickle cell crisis: In patients with sickle cell disease, a crisis can cause severe flank pain due to vaso-occlusion in the kidneys.
- Aortic dissection or abdominal aortic aneurysm: These are life-threatening conditions that can present with flank pain among other symptoms.
- Ectopic pregnancy: In women of childbearing age, ectopic pregnancy can cause flank pain and is a medical emergency.
- Rare diagnoses
- Polycystic kidney disease (PKD): A genetic disorder characterized by the growth of numerous cysts filled with fluid in the kidneys, which can cause flank pain.
- Renal cell carcinoma: Kidney cancer, which can cause flank pain, hematuria, and a palpable mass.
- Retroperitoneal fibrosis: A rare condition characterized by the proliferation of fibrous tissue in the retroperitoneum, which can cause flank pain and obstructive uropathy.
- Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodic hypertension, sweating, and flank pain.