Hypoglycemia is the medical term for low blood sugar levels. Different conditions and medications can influence a person’s blood sugar levels and the body’s ability to regulate them.
The term hypoglycemia refers to low blood glucose. Typically, this describes when blood sugar levels drop below the target range of
In most people, the body is able to carefully regulate blood sugar levels. The hormone insulin plays an important role in managing blood glucose. However, certain health conditions, including genetic conditions, can cause problems with insulin and how the body controls blood glucose levels.
In this article, we will discuss the relationship between genetics and hypoglycemia.
Hypoglycemia occurs when a person’s blood sugar level drops below a healthy threshold. It may happen for a
Congenital hyperinsulinism (CHI) is a genetic condition that causes a person to produce high levels of insulin. This excessive production of insulin can result in a person experiencing frequent episodes of hypoglycemia.
Some health experts may also refer to CHI as persistent hyperinsulinemic hypoglycemia of infancy or
Type 1 (T1DM) and type 2 diabetes mellitus (T2DM)
Both of these types of diabetes involve genetic factors, and a person with diabetes may experience hypoglycemia. A person living with diabetes will typically have low blood sugar due to medication rather than the condition itself.
However, other factors, such as eating, physical activity, and stress, can also influence blood sugar levels.
For example, a person may administer insulin to reduce high blood sugar. If they miscalculate the dosage and give themselves too much, this will result in hypoglycemia.
CHI is a genetic condition where variations in certain genes cause the pancreas to secrete too much insulin. As the body is unable to regulate this secretion of insulin, it results in a person experiencing hypoglycemia.
Researchers have identified 14 genetic causes of CHI. Additionally, CHI may also be a feature of a syndrome, which refers to a collection of symptoms that often occur together.
Alterations in the
A person may inherit CHI in either an
In other cases, CHI can develop in a person whose parents do not have the condition.
Depending on the gene variation, there are different forms of CHI, which include:
- Diazoxide-responsive and diazoxide-unresponsive diffuse KATP HI: In these types, potassium channels, known as KATP channels, which help regulate insulin secretion, do not work properly.
- Focal KATP HI: This type only impacts an isolated or focal area of the pancreas.
- GDH-HI: The body secretes excess insulin when fasting or after consuming protein.
- Glucokinase HI: The beta cells in the pancreas are unable to stop insulin secretion when blood glucose is too low.
- HNF1a-HI and HNF4a-HI: These forms progress to diabetes in later life.
- Exercise-induced HI: In this rare form, exercise triggers excessive insulin release.
- SCHAD-HI: This form occurs due to problems with fatty acid metabolism.
- UCP2-HI: This rare form is not permanent and eventually resolves over time.
- FOXA2-HI: In addition to HI, this form also results in pituitary hormone problems.
- LINE HI: This form results from gene changes in the pancreas that may not be present in all cells.
- Other conditions: Other genetic syndromes, such as Beckwith-Wiedemann syndrome, Turner syndrome, Sotos syndrome, and Rubinstein-Taybi syndrome, may also lead to HI.
As CHI is a congenital condition, a child will usually display symptoms within the first few days of life. Symptoms typically relate to low blood sugars and may also vary depending on the degree of involvement of the pancreas. In infants, symptoms may include:
- poor feeding
- pallor (face paler than usual)
- blue discoloration
- rapid breathing
In older children, symptoms can include:
In severe cases, CHI can deprive the brain of important fuels, such as sugar. When this occurs, brain cells may be unable to make the energy necessary to work and can stop working. This can lead to brain damage and may manifest as a seizure disorder, learning disabilities, cerebral palsy, blindness, or even death.
A doctor will typically base a diagnosis of CHI on medical history, laboratory findings, and genetic testing.
Often, this will involve a number of measurements relating to the person’s blood hormone, sugar, and fat metabolism.
For example, a doctor may request a glucagon stimulation test. This involves administering a dose of the hormone glucagon. If a person’s blood sugars rise, this suggests that the hypoglycemia is due to excessive insulin action.
Additionally, a doctor may be able to perform a special imaging test to see and evaluate the extent of involvement in the pancreas. This can help to determine if the condition is impacting the whole pancreas or just a certain area.
Treatment for CHI will usually depend on the involvement of the pancreas and typically involves medication or surgery.
In most cases, people with CHI will require medications to reduce insulin production. This can include drugs such as diazoxide and octreotide. Additionally, people may also receive glucagon, as this can help to increase blood sugar levels.
If a person does not respond to medical therapy, then it may be necessary for surgical removal of part of or the entire pancreas. A special imaging test can help distinguish how much of the pancreas the surgeon needs to remove.
In many cases, evidence suggests that with a rapid diagnosis and appropriate treatment, it is less likely that a person with CHI will experience long-term effects of hypoglycemia. However, this may also depend on the form of CHI they have. For example, surgery is typically very successful in those with focal CHI.
Some people may require additional support in school and the workplace if CHI leads to issues with brain development. Additionally, while surgery to remove some or the majority of the pancreas is often effective, there is a chance that the person may develop diabetes and require insulin injections.
Congenital hyperinsulinism is a genetic condition that can lead to hypoglycemia. It causes a person to produce too much insulin, which can lead to low blood sugars.
It often occurs due to inheriting a gene alteration that impacts how the body regulates the secretion of insulin.