ACOX1 and hyperinsulinemic hypoglycemia, familial, 4: At the severe end of the clinical spectrum, in the neonatal-infantile and childhood period, the clinical presentation of DBP and ACOX1 deficiency can be indistinguishable from ZSDs, with severe hypotonia, seizures, liver disease and dysmorphia (Ferdinandusse et al 2006a, 2007; Poll-The and Gartner 2012).