Child Neurology: Clinical and Imaging Findings in a Child With <i>DHX37</i> Gene Variant: A Ribosomopathy Masquerading as Cerebral Palsy.

Abstract

DEAH-Box helicase 37 (<i>DHX37</i>) gene, encoding an RNA-helicase, is essential for ribosome biogenesis. Pathogenic variants in the <i>DHX37</i> gene result in a spectrum of ribosomopathies ranging from neurodevelopmental disorders with possible brain, vertebral, and/or cardiac anomalies (NEDBAVC syndrome, OMIM #618731) as well as disorders of sex development. Here, we describe a young boy with <i>DHX37</i>-related neurodevelopmental disorder with clinical and imaging findings masquerading as cerebral palsy. A 7.5-year-old boy presented with global developmental delay and generalized chorea of 6 months duration. He was born at 37 weeks gestation after an uneventful pregnancy with a birth weight of 2668 g. He had primary microcephaly and intractable epilepsy from infancy. Examination revealed microcephaly, spastic quadriparesis, generalized choreoathetosis and dystonia. MRI of the brain revealed T2-weighted hyperintensity in bilateral corticospinal tracts, posterior limb of the internal capsule (PLIC), corona radiata, external capsule, periventricular and deep white matter, as well as subcortical cysts. Diffusion-weighted images showed high signal in bilateral corticospinal tract and PLIC. As there were red flags pointing away from cerebral palsy such as primary microcephaly, refractory seizures, late-onset movement disorder, and persistent high signal on diffusion-weighted imaging, whole genome sequencing (WGS) was sent. WGS revealed a homozygous variant c.2417G>A (p.Ser806Asn) in the <i>DHX37</i> gene. He was managed with antiseizure medications and clonazepam. <i>DHX37</i>-related neurodevelopmental disorder should be included in the differential for cerebral palsy mimic as affected children have global developmental delay, primary microcephaly, seizures, and movement disorders and thus may masquerade as sequel of hypoxic ischemic encephalopathy.