Although this combination of clinical findings, in particular the leading neurological presentation, is rather uncommon for fatty oxidation defects,20,21 there is some clinical overlap with long-chain acyl-CoA dehydrogenase (LCHAD) deficiency and mitochondrial trifunctional protein (MTP) deficiency which resemble a primary OXPHOS deficiency. Here, ACADVL is linked to hyperinsulinemic hypoglycemia, familial, 4.