INS and hyperinsulinism: Persistent hyperinsulinism in infants and young children is typically due to defects in distinct genes (ABCC8, KCNJ11, GLUD1, GCK, HADH, SLC16A1, HNF4A, HNF1A, and UCP2) that are responsible for regulating insulin release and can result in focal or diffuse histopathological subtypes [1, 2].