Hypothermia in a patient with anorexia nervosa.

A young woman with anorexia nervosa had severe recurrent hypothermia. Initial evaluation revealed a thiamine deficiency. Administration of pharmacologic doses of thiamine improved voluntary food intake, and her temperature normalized. Following the restoration of body weight, withdrawal of supplemental thiamine produced a clinical relapse. After reinstitution of supplemental thiamine, the patient again became asymptomatic until she chose to consume a calorically-restricted diet. With progressive weight loss, hypothermia recurred and was unresponsive to thiamine therapy. Fortuitously, the patient's intake of sucrose was abruptly increased, and her body temperature normalized within seven days. The potential roles of thiamine and carbohydrate in thermoregulation are discussed.