MRI findings of hypomyelination in adenylosuccinate lyase deficiency

Abstract

Adenylosuccinate lyase deficiency is a rare genetic disorder with few reported cases in the United States. Magnetic resonance imaging findings in the brain include hypomyelination and low generalized parenchymal volume. Presented here is a case in a 3-month-old male who presented with hypotonia and seizures and was subsequently diagnosed with adenylosuccinate lyase deficiency. Given the rarity of this diagnosis, findings demonstrated in this case may prompt ordering physicians to broaden their approach to genetic testing in the setting of hypomyelination. Comparison is also made to more common hypomyelinating leukodystrophies.

Clinical and molecular characterization of patients with adenylosuccinate lyase deficiency

“…In this cohort, the frequency of ASD is similar in the two phenotypic classes, while there is a higher percentage of brain imaging anomalies in the severe group. In literature, various anomalies in brain tissue, including cerebral cortex atrophy, corpus callosum agenesis, delayed or absent myelination, white matter anomalies and lissencephaly, were reported in all three phenotypic classes [ 21 , 22 ]. In a previous series of seven patients [ 21 ], all patients with type I had brain anomalies and microcephaly since the first year of life; type II patients had milder, non-specific brain anomalies without microcephaly.…”