3-METHYLGLUTACONIC ACIDURIA - 10 NEW CASES WITH A POSSIBLE NEW PHENOTYPE

3-Methylglutaconic aciduria is an organic aciduria with diverse phenot ypic presentations. In more than half of the cases it is a 'neurologic or silent organic aciduria', and, except for one subtype, the biochem ical defect is unknown. This report describes 10 new patients. Four of them presented with early global neurologic involvement and arrested development. They rapidly became demented, developed myoclonus or toni c-clonic seizures, spastic quadriplegia, deafness and blindness, and d ied. Three had acidosis and hypoglycemia neonatally; later, myoclonus and deafness, and eventually severe mental retardation and spastic qua driplegia developed, One patient died. In three children who presented with sudden onset of extrapyramidal tract symptoms, with or without o ptic atrophy, the clinical presentation was significantly different fr om that described either for 'unspecified' type or for Costeff syndrom e. All three patients showed clinical improvement soon after treatment with coenzyme Q.