The rare disease that caused the death of Prince Frederik of Luxembourg is called Alpers syndrome, or Alpers-Huttenlocher syndromeand its incidence is estimated in one case out of 100,000-250,000. It is a serious childhood pathology characterized by regression of neurological development, epileptic crises refractory to treatment, liver failure and, in some cases, hypotonia and moderate development delay. The syndrome is mainly caused by mutations in the Polg nuclear gene, head of the replication of the mitochondrial DNA, present in numerous copies within orgies called mitochondria.
«The inheritance – reads the Telethon website – is of the recessive autosomal type: To express the symptoms, a mutation from each parent must be inherited, which are healthy bearers. As a consequence of mutations, patients have a severe depletion, that is, strongly reduced levels, mitochondrial DNA, especially in muscle tissue, in the nervous system and liver “.
The diagnosis is based on laboratory analysis results. “The neuronal spongiosis (loss of neurons) – reads still on the Telethon website – cannot be identified by magnetic resonance imaging (MRI), but determines brain atrophy and multiple injuries with accumulation of mobile water, visible signs with MRI. Biochemical analyzes show a deficit, in the liver and muscles, of the mitochondrial respiratory chain, a fundamental system for the production of energy in the mitochondrio. This is a direct consequence of the reduction of the amount of mitochondrial DNA ».
The diagnosis is confirmed by a genetic analysis that shows the presence of mutations on both polic copies of Polg. Genetic advice is possible, and prenatal diagnosis is available in families where the specific mutations of the gene involved are known. A decisive cure is not available and the treatment is symptomatic and palliative. Employment therapy, physiotherapy and/or speech therapy are recommended to preserve neurological function for as long as possible.
With the progress of the disease, tracheotomy, artificial ventilation and positioning of a gastric tube may be necessary. If the patient is in the post -infant age, it can be considered – on an exclusive medical recommendation – the liver transplant for the treatment of liver failure. The prognosis is unfavorable, with a life expectancy that varies from three months to 12 years from the debut of the disease.