Hypophosphatemia secondary to oral refeeding in anorexia nervosa

TLDR

Hypophosphatemia is a well‑known complication of refeeding syndrome in severe anorexia nervosa, typically linked to parenteral nutrition, but this report documents three cases of oral refeeding‑induced hypophosphatemia. The patients received high caloric intake—approximately 3,000 kcal/day for one inpatient with IV fluids, and large oral intakes at home for the other two—leading to rapid phosphate depletion. All three patients developed profound hypophosphatemia (down to 0.9 mg/dl in two cases and 1.7 mg/dl in the third) but phosphate levels returned quickly to normal after repletion, underscoring the need for vigilance during oral refeeding.

Abstract

Hypophosphatemia is a well-known complication of the refeeding syndrome in severe cases of anorexia nervosa, described mostly as a result of refeeding with total parenteral nutrition. Few cases have been reported secondary to either nasogastric or oral refeeding.The authors present three cases in which hypophosphatemia developed secondary to oral refeeding in severe anorexia nervosa.All 3 patients developed significant hypophosphatemia, to a low of 0.9 mg/dl in two cases and a low of 1. 7 mg/dl in the third. The first patient received close to 3,000 calories per day, along with intravenous fluids, in the hospital; the other 2 patients ate large amounts for several days at home. Caloric restriction and replenishment with phosphorous resulted in a rapid return of phosphorous values to normal levels.Those who treat severely malnourished patients with eating disorders, whether as inpatients or outpatients, need to be vigilant for the development of the refeeding syndrome, even in patients receiving oral refeeding alone.