Diencephalic syndrome in a child with chronic malnutrition.

Russell's diencephalic syndrome is a set of signs and symptoms characterized by extreme weight loss, with no impairment of height or head circumference, without changes in intake or appetite. It is due to hypothalamic dysfunction associated with space-occupying lesions in this region. It is a rare cause of malnutrition in pediatrics, so its diagnosis is often delayed. Here we describe the case of a 17-month-old male patient with weight loss for 3 months who was admitted to the pediatric inpatient ward due to suspected intestinal malabsorption syndrome. After ruling out the most common causes of malnutrition, the patient was diagnosed with pilomyxoid astrocytoma of the brainstem.