Tuberous Sclerosis

Question 1

Inheritance and genetics of TS?

Answer 1

Mutation is present either on the TSC1 gene (Ch9) or TSC2 gene (Ch16) encoding the proteins hamartin and tuberin.

Question 2

Key clinical features of TS complex?

Answer 2

Multiorgan involvement: brain, kidney, heart, lungs,
and skin.
(1) Seizures occur in almost all patients
and mental retardation affects slightly more than
half of patients.

(2) A variety of skin lesions are associated with TSC: Hypomelanotic macules (ash leaf spots) 60–90%; Multiple small clustered hypomelanotic macules (“confetti” spots); Adenoma sebaceum are small red-pink flat
topped lesions that are distributed in a butterfly-like
distribution on the face; Ungual fibromas; Shagreen patches are thick, slightly elevated flesh colored macules that are usually located in the lumbosacral region

(3) BRAIN: Cortical tubers in 60–90% [multiple supertentorial T2 hyperintense cortical/subcortical lesions which can calcify/enhance], Subependymal giant
cell astrocytoma (SEGA) in 15% [enhancing tumor in the caudothalamic grooze adjacent to Foramen Monroe], Subependymal nodules, 50% [subcentimeter, often enhance, often calcified], Epilepsy, 60–90%, Mental retardation, 45%,

(4) HEART: Rhabdomyoma of heart, 50%,

(5) RENAL: angiomyolipoma of kidneys, 70–80%.