A 19-year-old girl is brought into an eating disorder clinic for a several year history of anorexia nervosa. She agrees to undergo an intensive inpatient rehabilitation service. She is started on a monitored feeding program, but after eating several meals she begins to feel nauseous and develops some edema. Her laboratory values are significant for a serum potassium level of 2.8 mEq/L, phosphorus level of 1.2 mg/dL, and magnesium level of 0.8 mEq/L.
Which of the following is the most serious complication that can result from this syndrome?
A. Heart failureHeart failure. This patient has hypophosphatemia, hypokalemia, and hypomagnesemia, which are manifestations of the refeeding syndrome. This syndrome occurs after severely malnourished patients suddenly increase their nutritional intake, and treatment involves decreasing the level of nutritional intake and repleting important electrolytes and vitamins. The most concerning electrolyte change is the rapid decrease in serum phosphate. Whole body phosphate levels are depleted during the malnourished phase, and refeeding causes two things: increased utilization of phosphate to synthesize molecules such as ATP, and increased cellular uptake of phosphate as well as other electrolytes (e.g., potassium and magnesium). Hypophosphatemia can cause cardiac dysfunction leading to heart failure and possibly death. (B) Respiratory failure is another potential consequence of the refeeding syndrome, but can be addressed with mechanical ventilation. (C, D) Renal failure is not a common consequence of the refeeding syndrome, and central pontine myelinolysis (now known as osmotic demyelination syndrome) is a consequence of an overly rapid correction of hyponatremia.