Prof. Federico Vigevano (Rome): “Very rare and complex pathology, the contribution of the patient association is fundamental”
Epilepsy affects about 1% of the population and is a predominantly pediatric symptomatology. There are patients who do not have lesions of the nervous system, so epilepsy is compatible with normal psychophysical development. However, there are particularly complex situations in which the underlying pathology and epileptic seizures interfere with neurological and cognitive development, which are called “epileptic and developmental encephalopathies“. Such pathological states, often accompanied by disabilities of varying degrees and autism spectrum disorders, until a few decades ago were considered unexplained.
“Thanks to the progress of genetics today we know that many of these conditions are caused by specific genetic mutations that can favor or cause the manifestation of seizures and the consequent comorbidities,” explains Prof. Federico Vigevano, Director of the Department of Neuroscience of the Bambino Gesù Pediatric Hospital in Rome. “This is precisely the case with SCN2A.”
“SCN2A is the name of a gene encoding a part of the brain sodium channel located on chromosome 2 at position 24.3. This channel is an electrically activated “gateway” in the brain that allows sodium to enter/exit neurons, Vigevano explains, influencing brain excitability. Mutations in the SCN2A gene can generate an increase or loss of function of the sodium channel and can be expressed in different clinical conditions. We have also discovered, thanks to functional studies, that the two forms of disease also respond to different drugs. Unfortunately, however, we are talking about symptomatic treatments: for this type of epileptic encephalopathy to date there is no precision therapy”.
“The disease almost always begins with epileptic seizures – continues the expert – and is accompanied by a delay in psychomotor development already in the first months. But the symptoms have enormous variability. Hypotonia and breathing difficulties may arise, some children have a very serious disability and must resort to parenteral nutrition. In other cases the intellectual disability is mild, but autism spectrum disorders may appear.”
It is therefore a complex and also extremely rare disease. Today in Italy there are 22 patients, whose families are brought together by the SCN2A Italia Famiglie in Rete APS association. Probably, however, the diagnoses are many more.
“We are talking about pathologies with an incidence of one case every 10,30, <>,<> at most,” Vigevano points out. “They are very rare diseases, which are therefore diagnosed only in particularly advanced centers, but no center can have sufficient case history to do research. So it is necessary to network in order to collect an adequate case study on the one hand to define the clinical picture, on the other to do research on potential therapies.”
The best Italian centers, almost all pediatric, are involved in a European network dedicated to rare and complex epilepsies, called EpiCARE. “We are therefore in constant contact with the most important European centres,” adds the expert. “But this is not enough, in fact we are also involved in other international networks, thanks to which we are able to collect much larger cases. We are still far from a therapy that can change the natural history of the disease, but the animal model of disease already exists, on which the antisense nucleotide strategy (a specific technique of advanced therapies that acts by modulating our messenger RNA, which encodes the “instructions” for the production of proteins) is being tested. Of course, supporting research for such rare diseases is not easy, so patient representation is really fundamental: associations must support international networks and research. Associations can really do a lot both in terms of fundraising and stimulating the attention of health authorities and pharmaceutical companies. Stimulating research today is really crucial. This is also one of the objectives of the newly formed association SCN2A Italia Famiglie in Rete APS“.
These are rare diseases, therefore, even if not included in the ministerial list of rare diseases that give the right to exemption from tickets. “Epilepsy as a pathology is correctly recognized in Italy and also involves some exemptions, but epileptic encephalopathies such as SCN2A are rare diseases with high complexity and as such must be recognized“, underlines Vigevano. “Obtaining a specific exemption can help patients in many respects, mainly to be entitled to all the specialist and therapeutic services specifically related to the individual pathology, overcoming the regional differences that unfortunately characterize Italian healthcare.”
“The Department of Neuroscience and Neurorehabilitation of the Bambino Gesù Pediatric Hospital in Rome currently has about 5000 patients with epilepsy, 50% of whom with epilepsies not controlled by drug therapy. In our database we have about 250 patients with epileptic and developmental encephalopathy with proven genetic mutation. Together with the Meyer of Florence, the Gaslini of Genoa, the Besta Institute of Milan, the Institute of Neurological Sciences of Bologna, the Mondino Foundation of Pavia and the University Hospital of Verona, the Bambino Gesù represents one of the main Italian centers for rare and complex epilepsies”.
“Thanks to the progress of genetics today we know that many of these conditions are caused by specific genetic mutations that can favor or cause the manifestation of seizures and the consequent comorbidities,” explains Prof. Federico Vigevano, Director of the Department of Neuroscience of the Bambino Gesù Pediatric Hospital in Rome. “This is precisely the case with SCN2A.”