Hyperthyroidism in anorexia nervosa: case report and review of the literature

OBJECTIVE: To report hyperthyroidism as a cause of unexpected weight gain during the course of anorexia nervosa (AN). METHOD: A case report and review of the literature. RESULTS: A 42-year-old woman with a 27-year history of AN had involuntary weight gain when she became hyperthyroid, but lost weight after treatment of the hyperthyroidism. An increase in appetite has been reported when hyperthyroidism occurs during AN. CONCLUSION: Clinicians should include hyperthyroidism in the differential diagnosis of unexpected weight gain in AN.