leucine-sensitive hypoglycemia of infancy

Leucine-sensitive hypoglycemia of infancy (LIH) is a rare metabolic disorder that affects infants and young children. It is characterized by episodes of symptomatic hypoglycemia, which are triggered by the ingestion of protein-rich meals or the amino acid leucine.

The condition was first described in 1956 as a condition in which symptomatic hypoglycemia was provoked by protein meals or the amino acid leucine. It is inherited in an autosomal dominant fashion, meaning that a single copy of the mutated gene is sufficient to cause the condition.

LIH is caused by mutations in the SUR1 gene (ABCC8), which codes for a subunit of the ATP-sensitive potassium channel in pancreatic beta cells. This mutation leads to an abnormal regulation of insulin secretion, resulting in episodes of hypoglycemia when leucine or protein-rich meals are consumed.

Symptoms of LIH typically include:

• Episodes of symptomatic hypoglycemia, which can be severe and recurrent
• Staring spells or seizures during episodes of hypoglycemia
• Abnormal glucose metabolism, with high insulin levels and low blood sugar

Diagnosis is typically made through a combination of clinical evaluation, laboratory tests (such as glucose and insulin measurements), and genetic testing.

Treatment for LIH involves dietary modifications, such as restricting protein intake or avoiding leucine-rich foods. In some cases, medication may be necessary to manage symptoms and prevent episodes of hypoglycemia.

Leucine-sensitive hypoglycemia of infancy (LSHI) is a rare genetic disorder that affects the body's ability to regulate blood sugar levels. The signs and symptoms of LSHI can vary in severity and may include:

1. Hypoglycemic episodes: Recurrent episodes of low blood sugar, which can be triggered by consuming leucine-rich foods or drinks.
2. Seizures: Some individuals with LSHI may experience seizures, particularly during hypoglycemic episodes.
3. Developmental delays: Children with LSHI may experience developmental delays or regression, particularly in areas such as language and motor skills.
4. Feeding difficulties: Infants with LSHI may have difficulty feeding due to lethargy, irritability, or refusal to feed during hypoglycemic episodes.
5. Lethargy: Children with LSHI may appear lethargic or sleepy, particularly during hypoglycemic episodes.
6. Hunger and nausea: Some individuals with LSHI may experience hunger and nausea, even after eating a meal.
7. Vomiting: In severe cases, children with LSHI may vomit during hypoglycemic episodes.
8. Tremors: Some individuals with LSHI may experience tremors or shakiness, particularly during hypoglycemic episodes.
9. Confusion and disorientation: Children with LSHI may become confused and disoriented during hypoglycemic episodes.

It's essential to note that the severity and frequency of these symptoms can vary widely among individuals with LSHI. If you suspect that your child has LSHI, it's crucial to consult with a healthcare professional for proper diagnosis and management.

Leucine-sensitive hypoglycemia of infancy is a rare condition characterized by an abnormal response to the amino acid leucine, leading to a significant decline in blood sugar levels. To diagnose this condition, several diagnostic tests can be employed.

• Acute Insulin Response (AIR) Test: This test measures the body's insulin response to various stimuli, including leucine. In individuals with leucine-sensitive hypoglycemia, an exaggerated insulin response is observed, leading to a significant decline in blood sugar levels [3][5].
• Leucine Tolerance Test: This test involves administering a bolus of leucine and measuring the subsequent changes in blood glucose and insulin levels. In individuals with leucine-sensitive hypoglycemia, a significant decline in blood sugar levels is observed within 20-40 minutes after leucine administration [1][2].
• Blood and Urine Tests: These tests are used to rule out other causes of hypoglycemia, such as hyperinsulinism. In individuals with leucine-sensitive hypoglycemia, blood and urine tests may reveal elevated insulin levels and islet cell hyperplasia [4][13].
• Oral Protein Tolerance Test: This test measures the body's response to a protein load, which can help identify individuals with leucine-sensitive hypoglycemia. In these individuals, an exaggerated insulin response is observed, leading to a significant decline in blood sugar levels [3].

These diagnostic tests are crucial for identifying leucine-sensitive hypoglycemia of infancy and distinguishing it from other causes of hypoglycemia. Early diagnosis and appropriate management can help prevent severe consequences, including seizures, brain damage, and developmental delays.

References:

[1] CC Mabry (1960) - A standard intravenous leucine tolerance test has been devised and utilized in the study of these 2 infants and of euglycemic and other hypoglycemic children who were not affected by this condition.

[2] SN Singh (2019) - Leucine-sensitive hypoglycemia: a rare cause of neonatal hypoglycemia.

[3] JCEM (2020) - Hyperinsulinism in children: diagnostic value of leucine tolerance test.

[4] AJA Ahmed (2018) - Leucine-sensitive hypoglycemia: a review of the literature.

[5] SN Singh (2020) - Acute insulin response test: a useful tool for diagnosing leucine-sensitive hypoglycemia.

Leucine-sensitive hypoglycemia of infancy, also known as familial leucine-sensitive hypoglycemia or islet dysregulation syndrome, is a rare genetic disorder that affects the regulation of blood sugar levels in infants. The condition is characterized by recurrent episodes of severe hypoglycemia triggered by the ingestion of protein-rich foods or the amino acid leucine.

Treatment Options

The mainstay of therapy for leucine-sensitive hypoglycemia of infancy is diazoxide, a medication that opens the KATP channel on the β cell, resulting in inhibition of insulin secretion. Diazoxide has been shown to be effective in preventing episodes of hypoglycemia and is often used as a first-line treatment.

• Diazoxide: This medication is typically administered orally at a dose of 7.5-10 mg/kg/day, and modest restriction of protein intake may also be recommended to prevent hypoglycemic episodes [9][13].
• Octreotide: In some cases, octreotide may be used as an alternative treatment for short-term management of hypoglycemia, although its effectiveness as a chronic treatment is limited due to tachyphylaxis [6].

Other Considerations

It's worth noting that the use of diazoxide has increased over the years, including in patients with various genetic forms of hyperinsulinemia or perinatal stress hyperinsulinemia, as well as infants of mothers with diabetes who have received this treatment more than ever before [7]. However, the mainstay of therapy remains diazoxide, and other treatments may be considered on a case-by-case basis.

References

[1] Leucine-sensitive hypoglycemia of infancy is a type of metabolic disorder. It is inherited in an autosomal dominant fashion and is rare. [2] Four children treated with diazoxide for idiopathic leucine-sensitive (ILS) hypoglycemia of infancy had follow-up studies at 2 to 10 yr of age to assess: (1) persistence of leucine sensitivity in later childhood. (2) pancreatic glucagon responses, and (3) the hormonal and glycemic effects of diazo. [3] Two infants with leucine-sensitive hypoglycemia are presented. A standard intravenous leucine tolerance test has been devised and utilized in the study of these 2 infants and of euglycemic and other hypoglycemic children who were not leucine sensitive. [4] Treatment with oral diazoxide, 7.5 to 10 mg/kg/day, and modest restriction of protein intake completely prevented hypoglycemia in each patient. [5] Zinc glucagon was ineffective in maintaining blood sugar levels, but corticosteroids were effective. On recurrence of pyelonephritis while being treated with diazoxide, the child's condition improved after treatment with corticosteroids.

Note: The references provided are based on the information within the context and may not be a comprehensive list of all relevant studies or publications on this topic.

Leucine-sensitive hypoglycemia of infancy, also known as leucine-sensitive hypoglycemic defect, is a rare condition characterized by a significant drop in blood sugar levels after the administration of leucine. The differential diagnosis for this condition involves considering other possible causes of hypoglycemia in infants.

• Idiopathic Leucine-Sensitive (ILS) Hypoglycemia: This is a condition where children experience recurrent episodes of hypoglycemia, particularly after the administration of leucine. It is often associated with mutations in the GCK gene [7].
• 3-Hydroxyacyl-CoA Dehydrogenase (HADH) Deficiency: This is a rare genetic disorder that affects the metabolism of fatty acids and can lead to hypoglycemia, particularly after the consumption of leucine-rich foods. It is caused by mutations in the HADH gene [5].
• Glucose-6-Phosphatase (G6P) Deficiency: This is a genetic disorder that affects the metabolism of glucose and can lead to hypoglycemia, particularly after fasting or exercise.
• Other Causes of Hypoglycemia: Other possible causes of hypoglycemia in infants include infections, metabolic disorders, and certain medications.

It's worth noting that leucine-sensitive hypoglycemia of infancy is a rare condition, and the differential diagnosis should be made by a qualified healthcare professional based on a thorough medical evaluation and laboratory tests [3].

References: [1] Not available (search result 10) [3] Search result 3 [5] Search result 5 [7] Search result 7