Summary about Disease
Myxedema represents severe hypothyroidism, a condition where the thyroid gland doesn't produce enough thyroid hormone. It's a medical emergency when it progresses to myxedema coma, characterized by decreased mental status, hypothermia, and other systemic complications. Before progressing to coma, it manifests as pronounced symptoms of hypothyroidism.
Symptoms
Symptoms of myxedema (severe hypothyroidism) include:
Skin: Dry, thickened, and pale or yellowish skin; coarse, sparse hair; brittle nails
Face: Swelling, particularly around the eyes (periorbital edema); thickened lips and nose
Cognitive: Mental slowness, impaired memory, confusion
Cardiovascular: Bradycardia (slow heart rate), enlarged heart, decreased cardiac output
Gastrointestinal: Constipation
Neuromuscular: Muscle weakness, aches, and stiffness; delayed reflexes
Metabolic: Cold intolerance, decreased sweating, weight gain despite poor appetite
Psychiatric: Depression, apathy
Other: Hoarseness, fatigue, deep voice When progressing to myxedema coma, additional symptoms include:
Decreased level of consciousness (ranging from lethargy to coma)
Hypothermia (low body temperature)
Hypoventilation (slow and shallow breathing)
Hypotension (low blood pressure)
Seizures
Causes
The primary cause of myxedema is severe, untreated hypothyroidism. This can result from:
Autoimmune disease: Hashimoto's thyroiditis (the most common cause)
Thyroid surgery: Removal of the thyroid gland
Radioiodine therapy: Treatment for hyperthyroidism or thyroid cancer
Medications: Certain drugs (e.g., lithium, amiodarone) can interfere with thyroid hormone production.
Pituitary or hypothalamic dysfunction: These conditions can disrupt the signals that tell the thyroid gland to produce hormones (secondary or tertiary hypothyroidism).
Iodine deficiency: Rare in developed countries, but a significant cause globally.
Medicine Used
The primary treatment for myxedema is thyroid hormone replacement therapy, typically with levothyroxine (synthetic T4). In myxedema coma, treatment is more aggressive and may include:
Intravenous levothyroxine: To rapidly restore thyroid hormone levels.
Intravenous liothyronine (synthetic T3): May be used in addition to or instead of levothyroxine in severe cases.
Supportive care: Including mechanical ventilation for respiratory failure, treatment of hypothermia, management of hypotension, and correction of electrolyte imbalances.
Hydrocortisone: May be given to address possible adrenal insufficiency, as severe hypothyroidism can sometimes impair adrenal function.
Monitoring: Close monitoring of vital signs, cardiac function, and neurological status is essential.
Is Communicable
Myxedema is not a communicable disease. It is caused by a hormonal deficiency, not an infectious agent.
Precautions
Precautions to prevent myxedema involve:
Early diagnosis and treatment of hypothyroidism: Regular thyroid screening, especially for individuals at risk (e.g., those with a family history of thyroid disease, autoimmune disorders, or who have received radiation to the neck).
Adherence to thyroid hormone replacement therapy: Taking medication as prescribed and attending regular follow-up appointments with a healthcare provider to monitor thyroid hormone levels.
Awareness of medications that can interfere with thyroid function: Discussing potential risks with a doctor when starting new medications.
Avoidance of iodine deficiency: Ensuring adequate iodine intake through diet or supplements, especially in areas where iodine deficiency is prevalent.
Prompt medical attention for symptoms of severe hypothyroidism: Seeking immediate medical care if symptoms worsen or if there are signs of myxedema coma.
How long does an outbreak last?
Myxedema is not an outbreak-related disease. It develops as a result of untreated or undertreated hypothyroidism. The duration of the symptoms depends on how long the hypothyroidism has been present and how quickly treatment is initiated. If treated promptly, symptoms can begin to improve within days to weeks, but full recovery may take several months. Myxedema Coma is considered a medical emergency, and the duration until recovery depends on how quickly treatment is administered and the severity of the case.
How is it diagnosed?
Myxedema is diagnosed through:
Clinical evaluation: Assessing the patient's signs and symptoms, medical history, and risk factors.
Thyroid function tests: Measuring thyroid-stimulating hormone (TSH) and free thyroxine (free T4) levels in the blood. In myxedema, TSH is typically elevated (in primary hypothyroidism) and free T4 is low. T3 levels may also be measured.
Other blood tests: Electrolytes, glucose, cortisol, complete blood count (CBC) and arterial blood gas to evaluate overall health and identify other complications.
Electrocardiogram (ECG): To assess cardiac function.
Imaging studies: Chest X-ray may be performed to evaluate for infection or heart failure.
Ruling out other conditions: Considering other possible causes of similar symptoms.
Timeline of Symptoms
The timeline of myxedema symptoms can vary. In many cases, hypothyroidism develops gradually over months or years.
Early stages: Mild symptoms such as fatigue, weight gain, constipation, and dry skin may be present.
Progression: As hypothyroidism worsens, symptoms become more pronounced, including mental slowness, cold intolerance, muscle weakness, and swelling of the face and extremities.
Myxedema coma: In untreated or severe cases, myxedema can progress to myxedema coma, which is a life-threatening emergency. This can occur over a period of days to weeks in severe cases.
Important Considerations
Myxedema coma is a medical emergency: Prompt diagnosis and treatment are essential to improve survival.
Underlying conditions: It's important to identify and address the underlying cause of hypothyroidism to prevent recurrence.
Drug interactions: Be aware of potential drug interactions with thyroid hormone replacement therapy.
Lifelong treatment: Most people with hypothyroidism require lifelong thyroid hormone replacement therapy.
Monitoring: Regular monitoring of thyroid hormone levels is necessary to ensure optimal treatment.
Patient education: Patients should be educated about their condition, medication, and potential complications.
Special populations: Pregnant women with hypothyroidism require careful monitoring and adjustment of thyroid hormone dosage to ensure proper fetal development. Older adults may require lower starting doses of levothyroxine due to increased sensitivity to the medication.