Pancitopenia and refeeding syndrome in anorexia nervosa, regarding a clinical case

Anorexia nervosa is an eating disorder characterized by persistent energy restriction, distorted body image perception, and intense fear of weight gain. It frequently leads to severe malnutrition and multisystemic impairment. Prolonged energy deficiency disrupts hematopoietic function, resulting in pancytopenia. Refeeding syndrome represents a significant complication during nutritional support for anorexia nervosa patients, with hypophosphatemia potentially causing further hematopoietic damage.

A 32-year-old female patient with anorexia nervosa was admitted for "pancytopenia and chronic weight loss," presenting with a body mass index of 11.7 kg/m2. Four years prior, workplace stress triggered abnormal eating behaviors, resulting in a rapid weight loss from 45 to 30 kg within 2 months. Over the preceding 2 days, she reported worsening discomfort in her back and precordial region.

Investigations revealed pancytopenia, although a previous bone marrow aspiration had shown no abnormalities. The patient was diagnosed with anorexia nervosa and pancytopenia secondary to refeeding syndrome.

On day 3, phosphate reached a minimum of 0.32 mmol/L (enteral nutrition at 20 kcal/kg/d). A stepwise protocol was initiated, increasing enteral nutrition by 5 kcal/kg every 24 hours, reaching 30 kcal/kg/d by day 5 and maintained thereafter. Concurrent intravenous phosphate supplementation (0.6 mmol/kg/d) was initiated.

At discharge, body weight increased to 31 kg with an elevated reticulocyte count, though the white blood cell count remained low. At 1-month follow-up, hemoglobin rose to 80 g/L and white blood cells to 3.1 × 109/L. However, issues persisted with inadequate protein intake and noncompliance with psychological interventions; the patient refused bone marrow aspiration and outpatient psychological therapy.

A stepwise calorie escalation protocol effectively corrects hypophosphatemia in refeeding syndrome. Treatment requires multidisciplinary management and psychological support. Hematopoietic recovery in anorexia nervosa patients with refeeding syndrome necessitates an extended duration. The impact of higher calorie feeding on hematopoiesis warrants further investigation.