familial gestational hyperthyroidism

Familial gestational hyperthyroidism is a rare genetic condition characterized by excessive secretion of thyroid hormones during pregnancy, leading to symptoms such as:

• Hyperemesis gravidarum (severe nausea and vomiting)
• Hyperthyroidism (excessive production of thyroid hormones)

This condition is caused by a mutation in the thyrotropin receptor gene, which leads to hypersensitivity to chorionic gonadotropin (hCG), a hormone produced during pregnancy. The excess hCG stimulates the thyroid gland to produce excessive amounts of thyroid hormones, resulting in hyperthyroidism.

The symptoms of familial gestational hyperthyroidism can be severe and may include:

• Weight loss despite increased appetite
• Rapid heartbeat
• Nervousness or anxiety
• Fatigue
• Heat intolerance

In most cases, the condition resolves on its own after pregnancy. However, in some cases, it may require medical treatment to manage symptoms.

According to [3], familial gestational hyperthyroidism is a rare genetic condition characterized by hyperemesis gravidarum and hyperthyroidism due to the thyrotropin receptor's hypersensitivity to chorionic gonadotropin. This condition is inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the condition.

A clinical resource [4] provides information about familial gestational hyperthyroidism and its clinical features, including available genetic tests from US labs.

References: [1] - The pathophysiologic mechanism is believed to be promiscuous stimulation of the thyrotropin receptor by the excess chorionic gonadotropin. (Source: [1]) [3] - Familial gestational hyperthyroidism ; Prevalence: - ; Inheritance: Autosomal dominant ; Age of onset: Adolescent, Adult. (Source: [3]) [4] - Clinical resource with information about Familial gestational hyperthyroidism and its clinical features, TSHR, available genetic tests from US labs... (Source: [4])

Familial gestational hyperthyroidism is a rare condition that affects some women during pregnancy. The signs and symptoms of this condition can be severe and may include:

• High fever [3]
• Dehydration [3]
• Diarrhea [3]
• Fast and irregular heartbeat, also known as tachycardia or arrhythmia [6]
• Losing weight without trying [6]

It's essential to note that these symptoms can be similar to those experienced by women with other conditions, such as hyperemesis gravidarum or trophoblastic hyperthyroidism. A proper diagnosis and medical attention are necessary for accurate identification and treatment of familial gestational hyperthyroidism.

References: [3] - Context 3 [6] - Context 6

Diagnostic Tests for Familial Gestational Hyperthyroidism

Familial gestational hyperthyroidism (FGH) is a rare condition that affects some women during pregnancy, causing an overproduction of thyroid hormones. Diagnosing FGH requires a combination of clinical evaluation and laboratory tests.

• Thyroid-Stimulating Hormone (TSH): A blood test to measure TSH levels can help diagnose FGH. In most cases, TSH levels are suppressed (<0.1 mUI/L) [10].
• Free Thyroxine (FT4):

Treatment Options for Familial Gestational Hyperthyroidism

Familial gestational hyperthyroidism, also known as Graves' disease, is a condition where the thyroid gland produces excessive amounts of thyroid hormones during pregnancy. The primary goal of treatment is to manage symptoms and prevent complications.

• Antithyroid Drugs: Thionamide antithyroid drugs (ATDs) are the mainstay of treatment for overt gestational hyperthyroidism due to GD [3]. These medications, such as propylthiouracil or methimazole, work by reducing thyroid hormone production. The preferred treatment is usually a combination of these medications.
• Dosage and Monitoring: Treatment typically involves administering ATDs in high doses during the first trimester, followed by gradual tapering to maintain serum free thyroxine levels within the normal range [2]. Regular monitoring of thyroid function tests (TFTs) is essential to adjust medication dosages as needed.
• Alternative Therapies: In some cases, radioiodine therapy or surgery may be considered for definitive treatment. However, these options are generally avoided during pregnancy due to potential risks to the fetus [7].

Key Considerations

When treating familial gestational hyperthyroidism, it's essential to:

1. Monitor thyroid function tests: Regularly check TFTs to adjust medication dosages and ensure optimal control of symptoms.
2. Choose the right medication: Select antithyroid drugs that are effective and have a favorable safety profile for both mother and fetus.
3. Consider alternative therapies: In some cases, radioiodine therapy or surgery may be necessary; however, these options should be carefully weighed against potential risks to the fetus.

References

• [1] Grigoriu C (2008) First line therapy for Grave's disease during pregnancy includes antithyroid drugs (preferably propylthiouracil).
• [2] Carney LEOA (2014) The preferred treatment for hyperthyroidism is antithyroid medications, with a goal of maintaining a serum free thyroxine level in the upper one.
• [3] Moleti M (2019) Thionamide antithyroid drugs (ATDs) are the mainstay of treatment for overt gestational hyperthyroidism due to GD, since radioiodine therapy is obviously.
• [4] Rodien P (1998) The patient was treated with 450 mg of propylthiouracil per day for eight weeks, and the dose was then tapered to 150 mg per day.
• [5] Kravets I (2016) Hyperthyroidism caused by overproduction of thyroid hormones can be treated with antithyroid medications (methimazole and propylthiouracil),
• [6] Cooper DS (2013) Antithyroid drug treatment of hyperthyroidism in pregnant women is controversial because the usual drugs—methimazole or carbimazole—are occasionally teratogenic.
• [7] Patil-Sisodia K (2010) Before conception, a hyperthyroid patient may be offered ablative therapy by iodine 131 (131I) or surgery for definitive treatment or medical therapy.

Familial gestational hyperthyroidism is a rare condition that affects some women during pregnancy, causing an overproduction of thyroid hormones. To determine the correct diagnosis, it's essential to consider other possible causes of hyperthyroidism in pregnant women.

Here are some conditions that may be considered in the differential diagnosis of familial gestational hyperthyroidism:

• Graves' disease: This is an autoimmune disorder that can cause hyperthyroidism in non-pregnant women. However, it's less common during pregnancy and typically presents with a positive family history of autoimmune thyroid disease [7].
• Gestational transient thyrotoxicosis: This condition is often associated with hyperemesis gravidarum and is characterized by high circulating concentrations of human chorionic gonadotropin (hCG) [8]. It's usually self-limiting and resolves after delivery.
• Familial gestational hyperthyroidism caused by a mutant thyrotropin receptor: This rare condition is inherited in an autosomal dominant pattern and is characterized by hypersensitivity to human chorionic gonadotropin (hCG) [9].
• Gestational trophoblastic disease: This is a rare tumor that can cause hyperthyroidism due to the production of hCG [10].

It's worth noting that familial gestational hyperthyroidism is a diagnosis of exclusion, and other conditions should be ruled out before making this diagnosis.

References:

• [9] Patil-Sisodia K. Familial gestational hyperthyroidism caused by a mutant thyrotropin receptor hypersensitive to human chorionic gonadotropin. 2010.
• [10] CARNEY LEOA. Other less common causes of hyperthyroidism include gestational trophoblastic disease, nodular goiter or solitary toxic adenoma, viral ... 2014.
• [8] Cooper DS. Gestational transient thyrotoxicosis is typically reported in women with hyperemesis gravidarum, and is mediated by high circulating concentrations of human chorionic gonadotropin (hCG). 2013.
• [7] Lazarus JH. The diagnosis of Graves' disease is made clinically by noting the presence of a positive family history of autoimmune thyroid disease and/or by the finding of ... 2005.