MedGen

A rare disorder of ketone body transport characterized by recurrent episodes of ketoacidosis provoked by fasting or infections in the first years of life. The episodes are typically preceded by poor feeding and vomiting and are associated with dehydration, in severe cases also with decreased consciousness and insufficient respiratory drive. Hypoglycemia is observed only infrequently. Patients with homozygous mutations tend to present at a younger age, have more profound ketoacidosis, and may show mild to moderate developmental delay in addition. [from SNOMEDCT_US]

The severity of congenital hyperinsulinism varies widely among affected individuals, even among members of the same family. About 60 percent of infants with this condition experience a hypoglycemic episode within the first month of life. Other affected children develop hypoglycemia by early childhood. Unlike typical episodes of hypoglycemia, which occur most often after periods without food (fasting) or after exercising, episodes of hypoglycemia in people with congenital hyperinsulinism can also occur after eating.

Congenital hyperinsulinism is a condition that causes individuals to have abnormally high levels of insulin. Insulin is a hormone that helps control levels of blood glucose, also called blood sugar. People with this condition have frequent episodes of low blood glucose (hypoglycemia). In infants and young children, these episodes are characterized by a lack of energy (lethargy), irritability, or difficulty feeding. Repeated episodes of low blood glucose increase the risk for serious complications such as breathing difficulties, seizures, intellectual disability, vision loss, brain damage, and coma. [from MedlinePlus Genetics]

A rare metabolic myopathy with characteristics of muscle cramping and/or stiffness after exercise (especially during heat exposure), post-exertional rhabdomyolysis and myoglobinuria and elevation of serum creatine kinase. Caused by mutation in the SLC16A1 gene. [from SNOMEDCT_US]