Un’anticipazione dal Workshop sulle Genetic Epileptic Encephalopathies
Tra i docenti del Workshop “The genetic epileptic encephalopathies” (Firenze, 8-10 settembre 2016), il prof. Georg F. Hoffmann della University Children´s Hospital di Heidelberg, in Germania, terrà un intervento dal titolo “Inherited metabolic disorders presenting as epileptic encephalopathy – Clinical cases, overall phenotype and the place for metabolic investigations”. Ecco in anteprima il suo abstract: «Epilepsy is a frequent symptom in inborn errors of metabolism with virtually no specific seizure types or EEG signatures. Convulsions are considered to reflect grey matter involvement in neurodegenerative disorders but may also be prominent in acute metabolic decompensation. For the most part, the semiology of seizures or EEG patterns does not depend on the underlying disorder, but is rather determined by age at presentation. However, seizures in metabolic disorders are more often focal than generalized. One of the most important aspects in the differential diagnosis of epilepsy caused by metabolic disorders is the age of onset of seizures. Diagnoses to consider in a neonate or infant are completely different from possible diagnoses in school-aged children, and less metabolic epilepsies presenting beyond infancy are amenable to metabolic interventions. Exceptions are mitochondrial disorders in which epilepsy can start at any age. It is most important to quickly look for those inborn errors of metabolism in which specific therapies such as supplementation of cofactors or diets can make all the difference. Neurometabolic diseases are especially to be suspected when the course of the disease is progressive or when additional neurological systems or other organs become involved. An important clue is the coexistence of different neurological features that cannot be explained by a “simple” neuroanatomic approach. In the majority of patients, conventional antiepileptic drugs must be used according to the seizure type. Valproic acid should be avoided in children with Alpers disease, other mitochondrial disorders but also urea cycle defects and organoacidopathies as it can trigger fatal liver failure. Next-generation genetic approaches are entering the diagnostic world and help to solve a wide variety of diagnostically difficult cases. Especially “new” disorders manifesting with metabolic epilepsies are being delineated at a fast rate. EPG5-related Vici syndrome, adenosine kinase deficiency, and deficiencies of SLC25A1, ECHS1, TANGO2, SPATA5 or UBA5 are some disorders which could be delineated by our groups. Metabolic investigations can and will nevertheless not be replaced in the foreseeable future. Similar to whole exome sequencing improved metabolomics are developing with increased precision and coverage of most if not all neurometabolic disorders combining traditional analytical platforms, such as analyses of amino acids, organic acids, neurotransmitters, etc. Another promising approach is untargeted metabolomics, especially in a research setting. The diagnostic specificity, sensitivity as well as time to result is different for each approach with advantages for targeted metabolic investigations as compared to next generation genomic testing in the diagnostic approach of the individual child. Metabolic and genetic testing must mostly be persued in parallel».
Le iscrizioni al Workshop sono aperte sino ai primi di settembre. Per le info e il programma si veda il sito della FM.