Genetic Testing Contributes to Diagnosis in Cerebral Palsy: Aicardi-Goutières Syndrome as an Example

Abstract

Cerebral palsy (CP) is a non-progressive neurodevelopmental disorder characterized by motor impairments, often accompanied by co-morbidities such as intellectual disability, epilepsy, visual and hearing impairment and speech and language deficits. Despite the established role of hypoxic-ischemic injury in some CP cases, several studies suggest that birth asphyxia is actually an uncommon cause, accounting for <10% of CP cases. For children with CP in the absence of traditional risk factors, a genetic basis to their condition is increasingly suspected. Several recent studies indeed confirm copy number variants and single gene mutations with large genetic heterogeneity as an etiology in children with CP. Here, we report three patients with spastic cerebral palsy and a genetically confirmed diagnosis of Aicardi-Goutières syndrome (AGS), with highly variable phenotypes ranging from clinically suggestive to non-specific symptomatology. Our findings suggest that AGS may be a rather common cause of CP, that frequently remains undiagnosed without additional genetic testing, as in only one case a clinical suspicion of AGS was raised. Our data show that a diagnosis of AGS must be considered in cases with spastic CP, even in the absence of characteristic brain abnormalities. Importantly, a genetic diagnosis of AGS may have significant therapeutic consequences, as targeted therapies are being developed for type 1 interferonopathies, the group of diseases to which AGS belongs. Our findings demonstrate the importance of next generation sequencing in CP patients without an identifiable cause, since targeted diagnostic testing is hampered by the often non-specific presentation.

Keywords: aicardi goutières syndrome; cerebral palsy; genetic diagnosis; genetic testing; next generation sequencing.

Figure 1

Brain MRI findings in our AGS patients: (A) Periventricular and frontoparietal lesions suggestive of cortical and white matter infarctions associated with (B) moyamoya disease at the distal left internal carotid artery and the proximal right middle cerebral artery on MR angiography in patient 1. (C) Isolated posterior thinning of the corpus callosum in patient 2. (D) Bilateral frontal periventricular microcysts and diffuse white matter hyperintensities in patient 3.

Figure 2

Chilblain lesions appearing in winter time on hands (A) and feet (B) of patient 2.