Transcript Maybe It’s My Thyroid…..

Thyroid disorders
in everyday care
Chris Vreeland, RN, MSN, NP-c
Georgia Mountain Endocrinology, PC
Introduction
• One in ten Americans have a thyroid
disorder
• Body’s response to thyroid disorders
is fatigue - most common reason to
seek healthcare.
• Women particularly affected by
thyroid imbalance
Weight
Fertility
Pregnancy
Menopause
Osteoporosis
Thyroid Hormone Action
• Activates nuclear receptors which
regulate expression of thyroid
hormone-responsive genes:
Fetus & neonate: differentiation
of target tissues
Childhood:
differentiation/proliferation
Adolescent: role in action of sex
steroids
Thyroid Hormone Action
• Gene expression (continued)
All ages:
• Regulates energy production
• Regulates functional
/structural proteins
• Regulates action of other
hormones - glucocorticoids,
mineralocorticoids, growth
factors, biologic amines
(catecholamines)
Negative Feedback Loop
• Thyroid hormone inhibits pituitary
secretion of TSH
• Hypothalamus plays crucial role
• TSH very sensitive indication index
of action
• TSH & thyroid hormones maintained
in a certain relationship
• Modified by TBG (thyroxine-binding
globulin)
Negative Feedback Loop
Hyperthyroidism
• Elevated serum thyroid level
• Decreased TSH
Hypothyroidism
• Decreased serum thyroid levels
• Increased TSH
Serum Levels of Thyroid
Hormones
• T3 regulates peripheral action of
hormone
• T3 & T4 both released from gland
• Peripheral conversion of T4 to T3
occurs in liver and target tissues
• In presence of liver damage, T3
conversion may be low despite good
levels of T4
TBG Metabolism
• T4 transported to tissue by TBG
• High serum TBG (liver damage,
pregnancy, OCP’s, HRT) lowers
serum concentrations of free T4
which decreases amount of
substrate (T4) that can be converted
to T3
• Indirect measure of TBG
abnormality is T3 uptake
Causes of Thyroid
Disorders
Hyperthyroidism
• Graves’ disease:
• Autoimmune
• TSH receptor antibodies
• Thyroiditis:
• Sub-acute
• Post-partum
• Pituitary tumor - TSH producing
Causes of Thyroid
Disorders
Hypothyroidism (High TSH, low T3,
T4)
• Hashimoto thyroiditis:
• Autoimmune
TPO and thyroglobulin antibodies
• RAI: radioactive iodine ablation
• Surgery
• Antithyroid drugs
• Goitrogens: lithium, amiodarone
Normal Hormone Levels
• TSH: 0.4-5.5 MIU/L
• Total T3: 60-181 NG/DL
• Total T4: 4.5-12.5 MCG/DL
• T3 Uptake: 22-35%
Hypothyroidism
Symptoms
 Fatigue
 Weight gain
 Cold feeling
 Dry hair, nails,
skin
 Hair loss
 Heavier or
longer menses
 Constipation
 Peripheral
edema
 Periorbital
edema
 Bradycardia
 Hypotension
 Infertility
Hypothyroidism
• Treatment:
• Hormone replacement (L-T4)
Absorbed from small intestine
6-day half-life
• Daily dosing: 0.025-.300 mgs
• Branded preparations preferred to
generic
Synthroid
Levoxyl
Tirosint
Hypothyroidism
• Treatment
Initial dose:
1.7 mcg per kg
Pregnant: may need 1.8 mcg per
kg
Elderly: usually start at lower
doses, esp. with angina or CAD
• Monitoring
6-8 weeks after any dose change
Annually once stable
Each trimester in pregnancy
Hypothyroidism
• Myxedema Coma
End stage of uncompensated
hypothyroidism
Presents most often in elderly and
women in winter months
Present in respiratory failure,
hypotension, bradyarrythmia,
along with serious precipitating
illness
Treatment is T4 IV @ 1/10th dose
of oral
ICU admit for multi-system failure
Hypothyroidism
Pearls
Most patients reports feeling best
with TSH between 1-2
If TSH normal, but patient still not
feeling good, think low T3; may
need Cytomel (oral T3)
Depression very common
Inadequate treatment can
contribute to infertility
Look for recent onset of symptom
with family history of thyroid
disease
Hyperthyroidism
Symptoms
Anxiety
Palpitations
Unintended weight loss
Decreased or absent menses
Oily skin
Fine, silky, oily-appearing hair
Heat intolerance
Exopthalmos (not all cases)
Tachycardia
Hyperthyroidism
Treatment
• Anti-thyroid drugs
 Methimazole
Inhibits thyroid hormone synthesis
in the thyroid gland
 PTU
Inhibits thyroid hormone synthesis
in the thyroid gland & inhibits
peripheral conversion of T4 to T3
Hyperthyroidism
Dosing:
• Tapazole: 10 mg BID or TID
• PTU: only 50 mg tablets
available
Usual starting dose: 2 tabs
TID; may double dose if
necessary
• Both very effective at lowering
thyroid hormone levels
• TSH will stay suppressed several
month
Hyperthyroidism
Dosing:
Monitor every 4-6 weeks
When TSH rises, may need to
add T4 (thyroid hormone)
Want to leave on ATD’s long
enough to allow TSH receptor
antibodies to decrease & induce
remission; usually 12-18 months
Plan to withdraw med at 12-18
months to evaluate remission
status
Hyperthyroidism
Side effects of anti-thyroid drugs:
• Leucocytopenia
• Agranulocytosis-most serious
• Pernicious anemia
• Thrombocytopenia
• Hepatic dysfunction
• Allergy (discoid rashes)
Evaluate with CMP, CBC, & thyroid
hormone levels every 4-6 months
Hyperthyroidism
Radioactive Iodine Ablation
• Administration of I131 iodine by
mouth
• Used after TFT’s normal or if
unable to control
hyperthyroidism with drugs
• Usually destroys gland over 3-6
months
Hyperthyroidism
Radioactive Iodine Ablation
• Induces permanent hypothyroidism
• May cause post-treatment thyroid
storm (rare)
• May cause aggravation of Graves’
eye disease
• Pregnancy should be prevented
within 6 months after treatment
Hyperthyroidism
Surgery
• When disease state or gland size
can’t be controlled with drugs
• When gland causing obstructive
signs
Difficulty breathing either supine
or upright
-Evaluated by PA & LAT CXR
Difficulty swallowing food
-Evaluated by barium swallow
Hyperthyroidism
• Thyroid Storm
• Most often with Graves’ disease
• Levels same as with Graves’
• Cardinal signs:
Temperature 102 to 1050
Profuse sweating
Marked tachycardia (120-140
pulse rate or higher)
Atrial fibrillation
• Usually induced by concurrent
infection or surgery on
hyperactive gland
Hyperthyroidism
Thyroid storm
• Treatment
PTU orally or by NG tube
Tapazole not favored because it
does not inhibit peripheral
conversion of T4 to T3
Beta blockade, PO or IV
Supportive therapy for fever,
dehydration
Perhaps iodine solution or
corticosteroids
Hyperthyroidism
Graves’ Eye Disease:
• Caused by antibody effect on orbital
tissue
• Symptoms include:
Edema
Inflammation
Hypertrophy of extra ocular
muscles & orbital fat
• Exopthalmos upper & lower lid
retraction, strabismus, herniated
orbital fat
Hyperthyroidism
Graves’ Eye Disease:
• Should be stabilized for 6 months
prior to any other treatment modality
• Exception is optic neuropathy
caused by strangulation of optic
nerve
• Extent of protrusion measured by
increase in distance between lateral
orbital rim and anterior aspect of eye
Thyroid Nodules
• May be a single nodule or larger of
multiple nodules
• 95% benign
• More common in women
• More likely malignant in men
• Increase in size while on T4 therapy
worrisome for malignancy
Thyroid Nodules
• Note size, consistency and mobility
on physical exam
• Evaluate for tracheal deviation or
esophageal obstruction
• Usually TSH suppressed, T3 and T4
levels normal
• Antibodies may be present, but
more likely they are not not
• Ultrasound best way to diagnose
Thyroid Nodules
Treatment
• Multinodular gland without
dominant nodule: T4 to shrink if
TSH not suppressed
• Single nodule 1 cm or greater:
fine needle aspiration biopsy
• Enlarging nodule despite “good”
dose of T4 or indeterminate or
malignant result from FNA
indicates need for surgery
Thyroiditis
• Most common cause: chronic
autoimmune thyroiditis or postpartum thyroiditis
• Next is sub acute thyroiditis
• More rare: acute suppurative
thyroiditis
Thyroiditis
Post-partum thyroiditis
• May occur anytime in the first year,
but most common in first 3 months
• Usually have hyperthyroid
symptoms first, followed by
hypothyroid findings
• Gland usually enlarged
• Will not have other markers for
inflammation: fever, tenderness,
high sed rate
Thyroiditis
Post-partum thyroiditis
• Usually spontaneously resolve
• May need temporary medication
support for symptoms
Beta blockers for tachycardia
Tranquilizers for anxiety
T4 for hypothyroidism
• Can progress to permanent
hypothyroidism
Thyroiditis
Sub acute
• Usually follows viral illness
• Gland is swollen, tender
• Sed rate elevated >50mm/hour
• May have fever, even fairly mild
• Leucocytosis
• Follows usual pattern of transient
hyperthyroidism, then
hypothyroidism, then euthyroid
Thyroiditis
Sub acute
• Treatment:
Symptomatic
NSAIDS for pain, fever
Prednisone for severe pain
unrelieved by above
Beta blockers for hyper phase
Thyroid replacement for hypo
phase
Resolve spontaneously
Questions?
Thank you!