| General Illness Information |
Common Name: |
Hypothyroidism |
|
Medical Term:
|
Hypothyroidism |
| Description: |
|
The thyroid gland
produces thyroid hormones, under the control of the
pituitary gland in the brain. Thyroid hormone is essential
to the body in the consumption of oxygen by the cells, and
in protein synthesis.
|
|
The condition in which
the thyroid gland produces low levels of thyroid hormone is
termed hypothyroidism.
|
|
It affects both sexes,
but is more common among women.
|
|
| Causes: |
|
Sometimes unknown.
Most common causes
include:
|
|
Auto-immune disease, in
which the body's immune system functions abnormally and
attacks the thyroid gland depleting its thyroid hormone
producing cells.
|
|
Radioactive iodine
treatment. for Graves Disease.
|
|
Surgery for
hyperthyroidism.
|
|
Iodine deficiency in the
diet. This is common in mountainous areas in the
underdeveloped world.
|
|
Decreased activity of
the pituitary gland, which secretes a thyroid-stimulating
hormone.
|
|
Use of drugs, such as
lithium, that may depress thyroid function.
|
|
| Prevention: |
|
No known measures to
prevent primary hypothyroidism.
|
|
However the addition of iodized
salt prevents goiter and hypothyroidism in mountainous areas
in the under developed world.
|
|
| Signs
& Symptoms |
|
Onset may be insidious, subtle
Weakness, fatigue, lethargy
Cold intolerance
Decreased memory
Hearing impairment
Constipation
Muscle cramps
Arthralgias
Paresthesias
Modest weight gain (10 pounds
[4.5 kg])
Decreased sweating
Menorrhagia
Depression
Hoarseness
Carpal tunnel syndrome
|
|
Dry, coarse skin
Dull facial expression
Coarsening or huskiness of
voice
Puffiness around the eyes
Swelling of hands and feet
Slow heart beat
Hypothermia
Reduced systolic blood
pressure
Increased diastolic blood
pressure
Reduced body and scalp hair
Delayed relaxation of deep
tendon reflexes
Anemia
Enlarged heart on chest x-ray
(often due to pericardial effusion)
|
|
| Risk Factors |
|
Five times more common
in females
Risk increases with
increasing age
Autoimmune diseases
|
| Diagnosis & Treatment |
|
Laboratory blood
studies of thyroid hormones.
Laboratory studies
can confirm the diagnosis of hypothyroidism, but they
cannot indicate how much replacement therapy is
needed.
Radio-immuno assay
may be done. Imaging studies are not generally
required.
|
|
Goals of treatment
are long-term thyroid replacement and recognition of
symptoms to avoid over or under-dosing.
|
|
| General
Measures: |
|
Goals of treatment
are to restore and maintain a normal thyroid state |
|
Need for lifelong treatment
Report to physician any signs
of infection, heart problems, or signs of toxicity from
thyroid replacement therapy. |
|
| Medications: |
|
The drug of choice is
Levothyroxine (Synthroid, Levothroid)
Dosage requirements may vary
with age, sex, residual capacity of thyroid gland, other
drugs being taken by patient, intestinal function
Elderly patients may require
lower dose.
|
|
|
|
| Diet: |
|
No restrictions. High
fiber diet to avoid constipation. |
|
| Possible
Complications : |
|
Treatment induced
congestive heart failure in people with coronary artery
disease
Myxedema coma - life
threatening complication of hypothyroidism
Increased susceptibility to
infection
Mega colon
Organic psychosis with
paranoia
Adrenal crisis with
vigorous treatment of hypothyroidism
Infertility
Over treatment for long
periods may lead to osteoporosis.
|
|
| Prognosis |
|
Excellent, with treatment.
|