Familial hyperinsulinism (related to ABCC8)
Congenital hyperinsulinism is the most common cause of persistent severe hypoglycemia in the newborn and childhood. It is due to altered glucose metabolism that can have diverse origins. Clinical manifestations appear very early, even prenatally, and are characterized by significant sustained hypoglycemia requiring high glucose inputs. This clinical picture of hypoglycemia also causes other derived clinical manifestations such as lethargy, hypotonia, tremor, irritability or apnea, which can lead in many cases to the appearance of important neurological sequelae.
Most cases of congenital hyperinsulinism are caused by the presence of monogenic mutations in two genes: KCNJ11 and ABCC8, which encode for the two subunits of the KATP channels of the beta-pancreatic cells. In particular, the mutations present in the ABCC8 gene are responsible for 50-60% of cases. These mutations cause a failure in the suppression of the release of insulin by the cell increasing its levels in blood in a pathological way.
The treatment must be early and aggressive whose main objective must be the control of blood glucose levels in order to avoid irreversible neurological damage. In some cases, total or partial pancreatectomy may be used.
GENE OR REGION STUDIED