Tuberous sclerosis (TS), or tuberous sclerosis complex (TSC), also known as Bourneville disease, is an autosomal dominant, multisystem disorder caused by mutations in the genes for the proteins hamartin and tuberin. It is characterized by tumor-like growths, or hamartomas, in almost every organ. Two-thirds of infants with TS/TSC are born to unaffected parents as a result of a sporadic mutation. During the neonate period and infancy, the most common presenting signs are seizures or cardiac rhabdomyomas, typically found on routine antenatal screening.

A majority of TSC patients will have epilepsy, and more than half will have developmental delays collectively termed TSC-associated neuropsychiatric disorders (TAND). Brain lesions including glioneuronal hamartomas and periventricular giant cell astrocytomas are commonly identified in patients with TAND.

Establishing the diagnosis of TS can be challenging due to the wide variation in severity and age-related penetrance of clinical manifestations. In some cases, diagnosis may be delayed until adolescence or adulthood.