Hypothalamic hamartomas (HH) are rare, non-cancerous (benign) tumors that develop in part of the brain called the hypothalamus. Hypothalamic hamartomas occur when the baby’s brain is forming (fetal development) and are present at birth. These tumors typically grow as the child’s brain grows. Hypothalamic hamartomas can cause early puberty (known as central precocious puberty), seizures with developmental delays (known as epilepsy and related neurobehavioral symptoms), or a combination of the two.
Children with central precocious puberty start to present with typical physical puberty features as early as 2 years of age. Children with epilepsy and related neurobehavioral symptoms often present with a specific type of seizure, known as gelastic (laughing) seizures, during infancy. Then, between the ages of 4 and 10 years of age, other types of seizures may develop. In addition, behavioral problems, tantrums, rage attacks and social isolation may occur. 40% of children who have seizures caused by hypothalamic hamartomas also have precocious puberty.
Babies and children who present with seizures or precocious puberty at a young age will likely have brain imaging performed. Hypothalamic hamartomas can be diagnosed with this imaging, which is typically a brain MRI (magnetic resonance imaging). Children who have precocious puberty caused by hypothalamic hamartomas can be treated with medications that correct hormone levels. Seizures caused by hypothalamic hamartomas do not respond well to seizure medications. If symptoms are severe enough, surgical removal of the hypothalamic hamartoma may be necessary. If your child has been diagnosed with a hypothalamic hamartoma, talk with your doctor to discuss the most current treatment options. Support groups can provide additional information and connect you with other families.