Familial Hyperinsulinism (ABCC8-Related) (ABCC8)
Recessive mutations in ABCC8 are a frequent cause of familial hyperinsulinism. While patients have been observed from many different ethnicities, there is an increased prevalence in individuals of Ashkenazi Jewish or Finnish descent due to the presence of founder mutations. While age of onset and severity can vary between patients, affected infants usually have a high birth weight. The inadequate suppression of insulin secretion results in severe hypoglycemia causing seizures and coma. This hypoglycemia can be difficult to regulate with diet and medication and may require surgical resection of the pancreas. Without early diagnosis and treatment, hypoglycemia may result in brain damage. With proper treatment, life expectancy is normal. Some patients may have a milder phenotype, which can make diagnosis difficult. The severity of the disease cannot be predicted based on the inherited variants. Heterozygous inactivating mutations in ABCC8 may also be causative of familial hyperinsulinism
For information about carrier frequency and residual risk, please see the residual risk table.