Pathogenesis

Familial forms of PHHI have been linked to mutations in the gene encoding the regulatory subunit of the beta-cell ATP-sensitive potassium channel.

The ATP-sensitive potassium channel closes when the blood glucose level is high resulting in depolarisation of the beta-cell membrane, an influx of calcium and the consequent release of insulin.

Cases of PHHI show no ATP-sensitive potassium channel activity and hence continually secrete insulin without regard to the blood glucose.

Reference:

• Ashcroft, FM. (1996). Sweet news for hypoglycaemic babies. Nature Medicine, 2(12), 1301-2.
• Kane, C. et al. (1996). Loss of functional K-ATP channels in pancreatic beta-cells causes persistent hyperinsulinemic hypoglycaemia of infancy. Nature Medicine, 2(12), 1344-7.