Acute presentation of leukodystrophy due to mitochondrial cytopathy and multiple deletions of mitochondrial DNA
Introduction. Deletions of mitochondrial DNA (mtDNA) are a known cause of various mitochondrial cytopathies, which are sporadic and usually not due to maternal transmission. The multiple deletions are usually transmitted on a Mendelian pattern, and are frequently of autosomal dominant character. Leukodystrophy may be part of the picture, or even the form of presentation, of some mitochondrial cytopathies. Thus, in a case of leukoencephaly of unknown origin, mitochondrial cytopathy should be considered in the differential diagnosis. Clinical case. We present the case of a boy with no previous clinical abnormalities who, at the age of 13, suddenly fell to the floor with an encephalopathy which required aggressive treatment, needing mechanical ventilation and prolonged sedation. Following partial recovery spastic-dystonic quadriplegia remained. Neuroimaging showed advanced leukodystrophy with small hemorrhages in the white matter, which later disappeared. After rejecting other aetiologies, mitochondrial cytopathies in muscle were studied. A partial defect of the I and IV complexes of the respiratory chain and two deletions of mtDNA were shown. Conclusions. This case is another example of the variable clinical presentation of mitochondrial cytopathies and yet another argument for their inclusion in the diagnosis of leukodystrophy of unknown origin
Caso clínico Se presenta el caso de un niño sin antecedentes personales de interés, que a los 13 años cayó al suelo bruscamente, padeciendo una encefalopatía que precisó tratamiento agresivo con ventilación asistida y sedación prolongadas, quedando, tras recuperación parcial, con tetraparesia espástico-distónica. La neuroimagen mostró una avanzada leucodistrofia junto a pequeñas hemorragias en sustancia blanca que posteriormente desaparecieron. Descartadas otras etiologías, se procedió al estudio de las citopatías mitocondriales en músculo. Se evidenció un defecto parcial de los complejos I y IV de la cadena respiratoria y dos deleciones del ADNmt.
Conclusiones El presente caso es otro ejemplo de la variabilidad en la presentación clínica de las citopatías mitocondriales y un argumento más para incluirlas en el diagnóstico diferencial de las leucodistrofias de causa no aclarada
