Goiter
-define
-possible causes
Enlarged thyroid gland
Hyper or hypothyroidism
Iodine, brussel sprouts, broccoli
Thyroiditis
Chronic autoimmune thyroiditis (AKA ___) can lead to -____
Inflammation of thyroid gland from viral/bacterial/fungal infection
Hashimoto’s Thyroiditis
-Hypothyroidism
How is thyroiditis diagnosed/treated if it’s chronic?
Consistent with diagnosis/treatment of hypothyroidism
Hyperthyroidism
-patho
-occurs in whom?
-most common form?
A sustained increase in the synthesis/release of thyroid hormones
Most common in women and 20-40 year olds
Grave’s Disease
Grave’s Disease
-patho
-precipitating factors
-can eventually lead to?
Autoimmune disease involving antibodies that mimic TSH, leading to increased thyroid hormone release
Most common form of hyperthyroidism
Precipitating: insufficient Iodine, infection, stress
Destruction of thyroid tissue can lead to hypothyroidism
Clinical manifestations of thyrotoxicosis can form
How does hyperthyroidism present?
High thyroid hormone:
-increased metabolism, increased tissue sensitivity to sympathetic nervous system
-Everything is ramped up (see slides)
Exophthalmos: eyes protrude from orbits
Thyrotoxicosis
-patho
-cause?
-manifestations?
-Treatment?
Emergency state of hyperthyroidism
-all manifestations are heightened
-additional stressors may be the cause
Severe tachycardia, HF, shock, hyperthermia, agitation, delirium, vomiting, coma, seizures
Antithyroid drugs
How do lab values with hyperthyroidism present?
TSH: will be low or undetectable
Free thyroxine/T4 will be high
(The high levels of T4 tell the pituitary to stop releasing TSH, which is why it’s low)
What kind of drugs are given for emergency thyrotoxic states?
-are they curative?
-surgical use?
-2 examples
Anti-thyroid drugs
-not curative
-help achieve euthyroid state before surgery
PTU (propylthiouracil)
Methimazole
PTU (propylthiouracil)
-use?
-safe for ___ patients?
-other MOA?
Anti-thyroid drug used for hyperthyroidism/thyrotoxicosis
Safe for pregnant patients
Blocks conversion of T4 into T3
Methimazole
-use?
-contraindication?
-AEs?
Used for hyperthyroidism and for thyrotoxicosis
Not safe for pregnancy/lactation
AE: peripheral neuropathy, fever/rash/itch, Gi upset, dizzy, agranulocytosis
IODINE
-use?
-MOA?
-example form
High doses block thyroid function
-used with other anti-thyroid drugs to prepare for thyroidectomy or to treat thyrotoxicosis
Lugol’s solution
Explain Radioactive Iodine Therapy
Treatment of choice for nonpregnant adults with hyperthyroidism
-damages/destroys thyroid tissue
-delayed response: up to 3 months- need meds to manage until it works
-hypothyroidism happens after procedure because the thyroid is destroyed, and they will need lifelong thyroid hormone replacement
When is surgery indicated for hyperthyroidism?
Unresponsive to drugs
Large goiter/tumor causing tracheal suppression
Possible malignancy
Pregnant-unable to do RAI
Hypothyroidism
-patho
-more common in ____
-2 types?
Deficiency of thyroid hormone-generally slows metabolic rate
-more common in women
Primary: from destruction of thyroid tissue or defective hormone synthesis (thyroid is problem)
Secondary: From pituitary disease with low TSH secretion or hypothalamic dysfunction (problem is not the thyroid itself, but insufficient stimulation of the thyroid)
What are possible causes of hypothyroidism?
Iodine deficiency (most common outside of US)
Gland atrophy (most common in US)
-end result of Hashimoto/Graves
From treatment of hyperthyroidism
How does hypothyroidism generally present?
What can severe/longstanding hypothyroidism lead to?
Everything slows down because metabolism slows down
-weight gain possible
Myxedema Coma
Myxedema Coma
Result of severe/longstanding hypothyroidism
Lethally low thyroid hormone levels
-medical emergency
-precipitated by infection/drugs/cold/trauma
-hypothermia, hypotension, hypoventilation
-vital functions need support
-IV thyroid hormone replacement necessary
Hypothyroidism:
-diagnosis/lab studies?
Serum TSH: determines cause of hypothyroidism
Elevated: Thyroid is defected (primary)
Low: pituitary/hypothalamus defected (secondary)
T4: always low
What is the goal of hypothyroidism treatment?
How is this done?
Restore euthyroid state ASAP
Low-calorie diet
Drug therapy
-Levothyroxine
-must take regularly
-AE: angina, cardiac dysrhythmias
-adjust dose according to thyroid hormone levels
If a dose of levothyroxine is too low, how does it present?
Bradycardia
Lethargy
Constipation
Excessive fatigue
Excessive sleeping
(looks like hypothyroidism)
If a dose of levothyroxine is too high, how does it present?
Irritability
Hyperthermia
Tachycardia
Diarrhea
Tremors
Insomnia
(looks like hyperthyroidism)
