What is TSC ?
Tuberous Sclerosis Complex is a genetic disease, either with familial origin or due to a genetic de-novo mutation as none of the 2 parents were affected. It is considered that 70 % of TSC cases are due to new mutations.
The disease is a part of a group of diseases, known as neuro-ectodermoses or neuro-cutaneous syndromes. It is characterized by benign tumors which can affect various organs (brain, kidneys and skin primarily; heart, eyes, lungs, less frequently)
Why are there micro-tumors in organs?
The genetic disorders of the Tuberous Sclerosis result in an abnormal cell signal transduction which produces a chain reaction. The misleading signals cause an erratic growth of cells and vessels. The inflammatory reactions are then transformed into definitive and fibrosing lesions.
In-vitro studies have recently proved that some fibrosing lesions could be reversible. This gives hope for future medical advances (see the section » Treatments and medical research » on this site).
What are the symptoms of TSC ?
Tuberous Sclerosis has various symptoms with very variable aspects from a patient to an other. Some will be only slightly affected, others more severely. The patients can present one or several symptoms according to their age or to the evolution of the disease.
The Tuberous Sclerosis has a strong penetrance, this means that almost all patients will be affected by at least a symptom, but with very variable expressiveness.
According to the scientific literature, 60 to 90 % of TSC patients will be affected by epilepsy during their life.
The onset of the disease is usually characterized by infantile spasms. The eyes roll upwards or sideswards, the child present spasms with flexions… The seizures may sometimes go unnoticed then become more frequent and intensify. We recommend you to react as quickly as possible. It is not harmless and patients need to see a neurologist as quickly as possible to avoid mental retardation. If necessary, do not hesitate to go to your hospital emergencies.
Infantile spasms in TSC usually appear around the 6th month of the life of the child. They are often associated with the « West Syndrome ».
Epilepsy can also be present under other forms, or at the age of adolescence or adulthood, as partial or generalized seizures.
The epilepsy of the Tuberous Sclerosis is associated with the presence of tubers (where the name of the disease comes from) which are small benign tumors.
Mental retardations, autistic disorders (autism) or behavior disorders in children or teenager may be directly due to Epilepsy. It is therefore important to control it as much as possible, whatever the seizures are.
At the cerebral level, sub-ependymal nodules sometimes develop and turn into giant cells, called Astrocytomas (or SEGA). Those can block the circulation of the cerebrospinal fluid in brain and lead to hydrocephalus. A follow-up by a neurologist and regular MRIs are then of utmost importance. When necessary, the nodules can be removed by neurosurgery, in very specialized centers, because this intervention is delicate.
Dermatologically, cutaneous achromic plaques are visible from the youngest age. Angiofibromas usually appear on the face during the teenage years. Angiofibromas can be more or less noticeable and sometimes come along with frontal plaques (shagreen plaque) or with other plaques in the lower back. The dermatological problems associated with TSC are very common in the adulthood and concern most of the patients.
Cardiac, renal and lung symptoms
In prenatal or neonatal periods, cardiac symptoms are known as Rhabdomyomas (mild cardiac tumors). Those tumors spontaneously reduce after a few years. Echography allows an early diagnosis. Cardiac insufficiency due to Rhabdomyomas presents a risk for the foetus or the newborn child, but remain rarely a problem later on.
As far kidneys are concerned, AngioMyoLipomas (AML) develop generally in the teenage years. They require then a regular follow-up as they present variable degrees of risk. The objective is to measure their size and their change to protect the renal function. They are more frequent in girls than in boys.
The young adult women are sometimes affected by lung disorders. Lymphangio Leiomyo Matosis (LAM) is particularly observed in the case of female patients having AML. It is likely that LAM is introduced or strengthened by the production of estrogens or by the migration of TSC cells to other organs.