Infantile Hypothalamic Hamartoma: A Rare Presentation of Isolated Obesity

Hypothalamic hamartomas (HHs) are rare, benign brain tumors or lesions of the hypothalamus that are predominantly identified in cases of epilepsy and central precocious puberty (CPP), whereas isolated manifestations of infantile obesity are atypical. We herein report an 8-month-old boy with severe obesity (Kaup index 26.4 [>100th percentile]) and uncontrollable hyperphagia. His growth chart demonstrated remarkable weight gain that exceeded the length gain in magnitude. Brain magnetic resonance imaging identified a lesion consistent with HH. There were no episodes or clinical findings of epilepsy, CPP, or Cushing disease. Hypothalamic obesity should be considered in the diagnosis even in infants with excessive weight gain due to overeating.