McKittrick-Wheelock syndrome: a rare cause of acute renal failure and hypokalemia not to be overlooked.

McKittrick-Wheelock syndrome is a rare disorder in which a colorectal tumor (usually a villous adenoma) determines secretory mucous diarrhea, which in turn leads to prerenal acute renal failure, hyponatremia, hypokalemia and metabolic acidosis. Even though the outcome is usually favorable with complete recovery after surgery, the diagnosis is often delayed, making the patient susceptible to life-threatening complications, mainly severe acidosis and hypokalemia. We present two paradigmatic cases with extreme electrolytes imbalance and complete recovery following the appropriate treatment. The pathogenesis of this degenerative condition is discussed in detail.