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Differential Diagnosis for Left Flank Pain, Nausea, and Poor Appetite

Single Most Likely Diagnosis

  • Nephrolithiasis (Kidney Stones): This condition is a common cause of flank pain, often accompanied by nausea and vomiting. The pain can be severe and may radiate to the groin. Poor appetite can be a secondary effect due to the discomfort and nausea.

Other Likely Diagnoses

  • Pyelonephritis: An infection of the kidney, which can cause flank pain, nausea, and decreased appetite. It often presents with fever and urinary symptoms.
  • Diverticulitis: Inflammation of a diverticulum in the colon, which can cause left flank pain if the diverticulum is located in the sigmoid colon. Nausea and poor appetite can also be present.
  • Gastroenteritis: Inflammation of the stomach and intestines, typically due to infection, leading to nausea, vomiting, and abdominal pain that can sometimes be localized to the flank area.

Do Not Miss Diagnoses

  • Appendicitis (if pain started near the belly button and moved): Although appendicitis typically presents with right lower quadrant pain, it can occasionally present atypically, especially if the appendix is retrocecal. Missing this diagnosis can lead to perforation and severe complications.
  • Ectopic Pregnancy: A pregnancy that develops outside the uterus, often causing severe abdominal or flank pain, nausea, and can lead to life-threatening bleeding if ruptured.
  • Abdominal Aortic Aneurysm: A swelling of the main blood vessel that leads from the heart and passes through the abdomen. Rupture can cause severe flank pain, nausea, and is life-threatening.
  • Pancreatitis: Inflammation of the pancreas, which can cause severe abdominal pain that radiates to the back, nausea, and vomiting.

Rare Diagnoses

  • Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodes of severe pain, including flank pain, nausea, and other systemic symptoms like hypertension.
  • Renal Cell Carcinoma: A type of kidney cancer that might cause flank pain, but typically presents with a triad of flank pain, hematuria, and a palpable abdominal mass.
  • Splenic Infarction: A condition where the spleen's blood supply is blocked, leading to tissue death. It can cause severe left upper quadrant or flank pain and is more common in individuals with sickle cell disease or other conditions that affect blood flow.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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