Early-onset dystonia and visual impairment preceding epileptic encephalopathy associated with PIGA gene mutation.

The association of dystonia and early-onset epileptic encephalopathy (EOEE) may have a genetic basis. Phosphatidylinositol glycan biosynthesis class A protein (PIGA) germline mutations have been described on the last decade and associated to refractory EOEEs. Dysmorphisms and visceral abnormalities have also been reported. Here we present the case of a now eight-month-old child who was evaluated for dystonia, visual impairment, and developmental delay at 2 months of age, followed by refractory focal seizures when he was four months old. The remaining examination was normal, besides an accelerated linear growth. His brain magnetic resonance and an extensive metabolic investigation failed to show any abnormalities. At seven months of age the exome sequencing found a hemizygous PIGA pathogenic variant - c.1352T>C (p.(Ile451Thr). Seizures improved after the association of carbamazepine to levetiracetam and the beginning of ketogenic diet. To our knowledge, this is the first time the phenotype associated to this specific mutation is described. Our patient had the singularity of manifesting with remarkable dystonia, over two months before the onset of seizures. We also point to the utility of gene sequencing approach in the diagnosis of patients with dystonia and EOEEs, since identification of the genetic cause may help in patient's management and families' empowerment.