Differential Diagnosis for Patient with Vomiting, Nausea, Elevated Serum Creatinine, and Unresponsiveness to Lasix

• Single Most Likely Diagnosis
  • Acute Kidney Injury (AKI): The patient's elevated serum creatinine and lack of response to Lasix (a diuretic used to increase urine production) suggest a problem with kidney function. AKI can be caused by various factors, including dehydration from vomiting, which could lead to a prerenal cause, or direct kidney injury from medications, toxins, or ischemia.
• Other Likely Diagnoses
  • Congestive Heart Failure (CHF): Although the patient does not respond to Lasix, which is commonly used to treat CHF, the medication's ineffectiveness could be due to severe kidney dysfunction or significant volume depletion. CHF can cause nausea and vomiting, and elevated creatinine can be seen in cardiorenal syndrome.
  • Liver Disease: Advanced liver disease can lead to hepatorenal syndrome, characterized by renal dysfunction in the setting of liver disease, which could explain the elevated creatinine and lack of response to diuretics. Nausea and vomiting can also be symptoms of liver disease.
• Do Not Miss Diagnoses
  • Sepsis: Sepsis can cause AKI, nausea, vomiting, and can lead to a state where patients do not respond to diuretics due to severe hypoperfusion and kidney injury. It's critical to consider sepsis due to its high mortality rate if not promptly treated.
  • Obstruction of the Urinary Tract: An obstruction in the urinary tract, such as from kidney stones or tumors, can cause acute kidney injury and prevent the kidneys from responding to diuretics. This condition requires urgent diagnosis and treatment to prevent permanent kidney damage.
• Rare Diagnoses
  • Contrast-Induced Nephropathy: If the patient recently underwent imaging studies involving contrast dye, this could be a cause of AKI, especially if the patient was already at risk due to pre-existing kidney disease or dehydration from vomiting.
  • Rhabdomyolysis: Although less common, rhabdomyolysis (breakdown of muscle tissue) can cause AKI and could potentially lead to nausea and vomiting. It's usually associated with muscle pain and very high levels of creatine kinase.