What is tuberous sclerosis?
Tuberous sclerosis complex (TSC) is a rare disease caused by changes (also called “mutations”) in certain genes that control important proteins in the body, hamartin and tuberin. These proteins control how cells grow, and tell them when to stop growing. If there is a problem with these proteins, it can make the body less able to stop tumors when they start growing.
TSC can affect several systems in the body. Patients with TSC develop benign (non-cancrous) tumors called hamartomas in the brain and other vital organs such as the kidneys, heart, eyes, lungs, and skin. Patients with TSC may experience a few or all of these symptoms: seizures, intellectual disability, delays in mental or physicial development, behavioral problems, skin abnormalities, or lung and kidney disease.
There are three types of brain tumors associated with TSC:
- Cortical tubers, after which the disease is named and in which small areas on the outside of the brain do not form normally,
- Sub-ependymal nodules, which form in the walls of the brain’s cerebral ventricles, small areas in the brain that contain cerebrospinal fluid (CSF), and
- Giant cell astrocytoma, which are tumors that can block the flow of CSF and cause symptoms.
In the kidneys and lungs, benign tumors and cysts are frequent, although malignant (cancerous) hamartoblastomas do sometimes occur as well. TSC may also cause sores called lesions on the skin or in the organs, so it is important for the medical team to monitor the patient closely to make sure these are treated.
Our approach to tuberous sclerosis
Although there are a wide range of symptoms, there are no definitive clinical signs for tuberous sclerosis. In infants, the first clue is often the presence of seizures, delayed physical and mental development, or white patches on the skin. A full clinical diagnosis involves a careful examination of the skin, imaging with a CT scan or MRI, and getting a detailed personal and family history.
There are drugs that are used to treat some forms of TSC, although they are currently in the developmental stage. The outlook for people with TSC depends on the severity of symptoms, which range from mild skin problems to some level of learning disabilities and epilepsy to, in more sever casese, intellectual disability, seizures, and kidney failure.
Those individuals with mild symptoms generally do well and live long productive lives, while individuals with the more severe form may have serious disabilities. However, with appropriate medical care, most people with the disorder can look forward to normal life expectancy.