Pituitary hypothyroidismis a rare condition characterized bylow levels of thyroid hormonedue to failure of thepituitary gland.
The pituitary gland is a pea-sized structure in the brain that releases thyroid-stimulating hormone (TSH).
This hormone circulates in the blood and tells the thyroid to release its own hormones.
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Pituitary failure can manifest with several potential symptoms.
Read on to learn more about the symptoms, diagnosis, and treatment of secondary hypothyroidism.
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Secondary Hypothyroidism Symptoms
Thyroid hormonesare involved in many metabolic processes throughout the body.
Symptoms of hypothyroidism generally include the following:
The symptoms listed above are common to primary and secondary hypothyroidism.
These symptoms can include:
Undiagnosed Hypothyroidism
At its most severe, undiagnosed hypothyroidism can manifest asmyxedema.
It requires hospitalization for urgent treatment.
What Causes Secondary Hypothyroidism?
The body functions best when hormone levels are maintained in the correct range.
To accomplish this, the brain and endocrine organs work together through complex feedback loops.
The process starts in the part of the brain called thehypothalamus.
Thehypothalamusreleases a hormone called thyrotropin-releasing hormone (TRH).
This hormone signals the pituitary gland to releasethyrotropin, also known as thyroid-stimulating hormone (TSH).
The T3 and T4 then interact with the hypothalamus, telling it to secrete more or less thyrotropin-releasing hormone.
Hypothyroidism is generally diagnosed withblood tests.Measuring low thyroid levels and circulating hormones can help determine where the problem is.
Fortunately, hypothyroidism is treatable with medication.
Thyroid hormones can be replaced with a synthetic thyroid hormone calledlevothyroxine.
Alternatively, desiccated thyroid hormone derived from thyroid glands of animals (known asArmour thyroid) can be administered.
In secondary hypothyroidism, hormone levels are monitored to ensure appropriate dosing of thyroid hormone.
The underlying cause of secondary hypothyroidism also needs to be addressed.
Pituitary tumors, one of the more common causes of secondary hypothyroidism, may requiresurgery.
Hypothyroidism is treatable with medication, including synthetic thyroid hormones.
The overall prognosis depends on the underlying cause.
Know that low thyroid hormone disorders are treatable, though it can take time to start feeling better.
Low T3 and T4 levels with normal or low TSH levels indicate a problem with the brain.
A brain MRI is needed for further evaluation.
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