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NURS 5433 Module 4 :NURS 5433 Module 4 Endocrine System
Exam Study Guide
HYPOTHYROIDISM
Asked on boards: What is the most common cause of thyroid disease? It
is autoimmune disease.
What is hypothyroidism? What is hyperthyroidism?
Hypothyroidism: reduction in the amount of circulating free thyroid
hormone, or from resistance to the action of the thyroid hormone
Risk factors:
family history
Age
females sex
hypothalamic disease
autoimmune diseases
radiation of head or the neck
treatment for hyperthyroidism
medications: amiodarone and lithium interferon
(female > 40 should have TSH checked yearly)
Presentation:
Lethargy
weight gain
swelling of the hands and feet
, 2
periorbital edema
menstrual problems
memory loss
cramps
delayed deep tendon reflexes
coarse skin
hair loss
decreased blood pressure
anemia
hyponatremia
hyperlipidemia (check a lipid panel in a patient with
hypothyroidism. It usually resolves once thyroid is functioning
properly)
sweating
constipation
Hypothyroidism: TSH elevated, T4 low Subclinical hypothyroidism: TSH
elevated, T4 normal
What is congenital hypothyroidism? What are signs and symptoms?
How is it treated? What happens if it is not treated?
Maternal hypothyroidism
o limited largely to the first trimester
o fetus is unable to produce thyroid hormones of its own
o 1st trimester: the child can develop permanent
neuropsychologic deficits without adequate thyroid
o 2nd trimester: the fetal thyroid gland is fully functional, and
hence the fetus can supply its own hormones from then on
, 3
o maternal hypothyroidism must be diagnosed and treated
very early o When women taking thyroid supplements
become pregnant, dosage requirements usually increase—
often by as much as 50%
o dosage begins between weeks 4 and 8 of gestation, levels off
at about week 16, and then remains steady until parturition
o Levothyroxine dosage can be reduced to pre-pregnancy
immediately after delivery
Hypothyroidism in newborns o congenital hypothyroidism can
cause delay in mental development and derangement of growth.
o child develops a large and protruding tongue
o potbelly o dwarfish stature o Development of the nervous
system, bones, teeth, and muscles is impaired. o In all
children, replacement therapy should continue for 3 years,
after which it should be stopped for 4 weeks
o If TSH rises, indicating thyroid hormone production is low,
we know the deficiency is permanent, so replacement
therapy should resume
o If TSH and T4 normalize, we know the deficiency was
transient, and hence further replacement therapy is
unnecessary
Referral to endocrinologist is indicated for congenital hypothyroidism.
Congenital hypothyroidism should be followed annually.
What lab values would you expect to see with primary hypothyroidism,
subclinical hypothyroidism, and primary hyperthyroidism?
Condition TSH Free T4 Level
Level
NURS 5433 Module 4 :NURS 5433 Module 4 Endocrine System
Exam Study Guide
HYPOTHYROIDISM
Asked on boards: What is the most common cause of thyroid disease? It
is autoimmune disease.
What is hypothyroidism? What is hyperthyroidism?
Hypothyroidism: reduction in the amount of circulating free thyroid
hormone, or from resistance to the action of the thyroid hormone
Risk factors:
family history
Age
females sex
hypothalamic disease
autoimmune diseases
radiation of head or the neck
treatment for hyperthyroidism
medications: amiodarone and lithium interferon
(female > 40 should have TSH checked yearly)
Presentation:
Lethargy
weight gain
swelling of the hands and feet
, 2
periorbital edema
menstrual problems
memory loss
cramps
delayed deep tendon reflexes
coarse skin
hair loss
decreased blood pressure
anemia
hyponatremia
hyperlipidemia (check a lipid panel in a patient with
hypothyroidism. It usually resolves once thyroid is functioning
properly)
sweating
constipation
Hypothyroidism: TSH elevated, T4 low Subclinical hypothyroidism: TSH
elevated, T4 normal
What is congenital hypothyroidism? What are signs and symptoms?
How is it treated? What happens if it is not treated?
Maternal hypothyroidism
o limited largely to the first trimester
o fetus is unable to produce thyroid hormones of its own
o 1st trimester: the child can develop permanent
neuropsychologic deficits without adequate thyroid
o 2nd trimester: the fetal thyroid gland is fully functional, and
hence the fetus can supply its own hormones from then on
, 3
o maternal hypothyroidism must be diagnosed and treated
very early o When women taking thyroid supplements
become pregnant, dosage requirements usually increase—
often by as much as 50%
o dosage begins between weeks 4 and 8 of gestation, levels off
at about week 16, and then remains steady until parturition
o Levothyroxine dosage can be reduced to pre-pregnancy
immediately after delivery
Hypothyroidism in newborns o congenital hypothyroidism can
cause delay in mental development and derangement of growth.
o child develops a large and protruding tongue
o potbelly o dwarfish stature o Development of the nervous
system, bones, teeth, and muscles is impaired. o In all
children, replacement therapy should continue for 3 years,
after which it should be stopped for 4 weeks
o If TSH rises, indicating thyroid hormone production is low,
we know the deficiency is permanent, so replacement
therapy should resume
o If TSH and T4 normalize, we know the deficiency was
transient, and hence further replacement therapy is
unnecessary
Referral to endocrinologist is indicated for congenital hypothyroidism.
Congenital hypothyroidism should be followed annually.
What lab values would you expect to see with primary hypothyroidism,
subclinical hypothyroidism, and primary hyperthyroidism?
Condition TSH Free T4 Level
Level
