Myxedema Coma: Symptoms, Contributing Factors, Treatment, Prevention, Diagnosis

Myxedema coma is a complication of advanced hypothyroidism and is also known as a myxedema crisis. It is the loss of brain function due to long-standing low thyroid hormone levels. It is a life-threatening complication.

Hypothyroidism is a condition in which the thyroid is not able to produce enough thyroid hormone.⁽¹⁾ The hormones produced by the thyroid are triiodothyronine (T3) and thyroxine (T4), which play a role in regulating several functions in the body, including:⁽²⁾

• Body temperature
• Metabolism
• Growth
• Heart

Lack of T3 and T4 disrupts body functions and leads to myxedema coma.

There are many conditions that may lead to hypothyroidism, including:

• Hashimoto thyroiditis
• Congenital hypothyroidism
• Pituitary gland abnormalities
• Shehan’s syndrome
• Iodine imbalance

Patients with myxedema coma have a history of hypothyroidism thyroid surgery and radioactive iodine treatment for the thyroid. In rare cases, the condition is not due to the inability of the thyroid gland but due to the failure of the pituitary gland, or the hypothalamus to send correct signals to the thyroid gland to function normally. Here the thyroid gland is normal but is not sending or receiving proper signals to make the thyroid hormone, it is capable of producing.

There are a few contributing factors that may trigger myxedema coma. These include:⁽³⁾

• Infection
• Trauma
• Stress
• Exposure to cold
• Stopping hypothyroidism treatment
• Sudden illnesses such as stroke and heart attack

It is important for those with hypothyroidism to try and keep warm. Also, a doctor should be consulted if any infection is taking longer than usual to get treated.

Myxedema coma occurs when the body is not able to tolerate the symptoms of hypothyroidism and the symptoms include:

• Low blood oxygen level
• Hypothermia
• Decreased breathing
• Shock
• Seizures
• Lower than usual blood sodium level
• Low oxygen levels
• Confusion and mental slowness
• Swelling of the body
• Slow heart rate
• Seizure
• Hallucination
• Reduced function of the digestive system

A doctor can measure the levels of T4 in the body to diagnose myxedema coma. Immediate hormone replacement is started which is based on the symptoms, even before the result comes. The symptoms include:

• Goiter
• Confusion
• Dry skin
• Sparse hair
• Decreased breathing
• Hypothermia
• Scar from any thyroid surgery
• Swelling on face and legs

More tests are performed to determine the thyroid function and other conditions affecting the thyroid.

The primary treatment involves giving the patient breathing treatment and helping him warm up. Antibiotics are started to cure the infection.

Patients with hypothyroidism without myxedema are treated with T4 hormone, but in the case of myxedema coma, the treatment is different. If myxedema coma is suspected, hormone replacement therapy is started to ease the symptoms by restoring the T3 and T4 hormone level. Normally T3 is a hormone that is metabolically active and is produced by the thyroid gland. In patients with no problem, T4 is converted into T3 in the bloodstream. In those with myxedema coma, the patient is so sick that this conversion is impaired. In such cases, T3 is started initially followed by T4 therapy as well.

Depending on the advancement of coma T3 and T4 hormones are administered using a drip. Oral treatment is given if the person is well enough to take it. Additionally, other medications including steroids are given.

The primary way to manage myxedema coma is to prevent this condition from occurring. The doctor should be visited regularly for follow-up and blood tests to determine the dosage is appropriate.

Anyone with symptoms that concerns them, should visit a doctor to discuss the concerns and explore the treatment options for hypothyroidism. If the treatment is started early most people with myxedema coma have a positive outlook. Without rapid diagnosis and treatment, the condition can prove to be fatal.