Paciente con lesión bilateral del estriado y distonía lentamente progresiva secundarias a la mutación T14487C en el gen ND6 del complejo I de la cadena respiratoria mitocondrial

Abstract

A large number of diseases present as bilateral striatal lesion syndrome (BSLS). Clinical manifestations, course and prognosis of these diseases are extremely variable. On the basis of their evolutive course, they can be separated into two major groups: acute, which include toxic, infectious or parainfectious causes, and subacute or chronic, in which inborn errors of metabolism, especially mitochondrial disorders, are the main causes. We report a detailed clinical follow-up of a 18 years old Caucasian male who, at the age of four, presented with BSLS. A respiratory chain defect was suspected on the basis of slowly progressive dystonia and cognitive impairment, changes in serial MRI studies, and the finding of 'trabecular fibers' as well as a 50% decrease of the complex I activity in striated-skeletal muscle specimen. Blood, urine and CSF markers classically associated with respiratory chain diseases were normal. Molecular studies identified a new pathogenetic mutation (T14487C) in the mitochondrial ND6 gene of the respiratory chain complex I. Mitochondrial metabolism disorders should be ruled out in patients presenting with a subacute or chronic form of BSLS even in the absence of other common mitochondrial disease markers.