DLD and hyperinsulinemic hypoglycemia, familial, 4: The severity of the clinical outcomes is due to the simultaneous defects of the mitochondrial E3-harboring multienzyme dehydrogenase complexes for alpha-ketoglutarate (KGDHc), pyruvate (PDHc), alpha-ketoadipate (KADHc), and branched-chain alpha-keto acids (BCKDHc); interestingly, the glycine cleavage system (GCS), which also contains the LADH protein, remains unaffected in E3-deficiency [1, 4, 20–22].