Sodium depletion and hemoconcentration: Overlooked complications in patients with anorexia nervosa?

Plasma volume depletion and hypovolemic hyponatremia are common in the most severely malnourished patients with anorexia nervosa. Clinicians should be aware that, because of malnutrition, the common indexes of hemoconcentration may be within normal range and that hemoconcentration may mask anemia. Further studies are needed to assess the role of neglected behaviors such as sodium and fluid restriction.