Takeaway
D-DEMØ represents an ATP1A3-associated phenotype characterized by neurological abnormalities which, when encountered in practice, should trigger investigation for ATP1A3 mutations.
Why this matters
The α3 subunit of the transmembrane sodium/potassium (Na+/K+) adenosine triphosphate (ATP)-ase ion pump plays a major role in maintaining the excitatory-inhibitory balance in multiple brain regions; reduction in activity of this subunit leads to a spectrum of neurologic disorders depending on the location and nature of the fault.
Identification of rare conditions such as ATP1A3 mutation-linked phenotypes that manifest at birth has implications for early diagnosis and consequent treatment strategies for these children.