Thyroid Flashcards
Thyroid Hormones
T4 produced in greater amounts, converted to active T3
-Stimulated by TSH (sec by AP)
Hyperthyroid Sx
-Weight loss
-Tremor
-Tachycardia
-Heat intolerance
-Sweating
-Enlarged neck
Hypothyroid Sx
-Weight gain
-Lethargy
-Dry skin
-Cold intolerance
-Loss of libido
-Voice hoarsening
Screening
Hyper = T4
Hypo = T3
Sick Euthyroid (Low T3)
-Acute injury
-Caloric deprivation
-Psych illnesses
Combo of low T3 and high reverse T3
Best test = TSH
T3/4 Interpretation
Low = hypothyroid
High = hyperthyroid
Elevations of the total T4 without hyperthyroidism are seen in:
-Increases in TBG (preg, estro, hepatitis, porphyria)
-Newborns (6 wk)
-Familial dysalbuminemic hyperthyroxinemia
Decreases of the T4 without hypothyroidism are seen in:
-Decreases in TBG (NS, GC, sal, pheny, hypoprotein)
-Drugs that displace T4 from TBG
Most Useful Test in Thyroidism (hypo/per)
TSH
-very useful test in distinguishing primary (thyroidal) and secondary (pituitary) hypothyroidism
TRH ‐ TSH Stimulating Test
TRH will increase TSH
*but no increase seen in pituitary hypothyroidism
High titers of anti-thyroglobulin and anti-microsomal antibodies are found in =
-Lymphotic thyroiditis (hashimoto’s)
-Lymphadenoid goiter (euthyroid)
Subclinical Hyperthyroidism
TSH < 0.1 and normal T3/FT4
Subclinical Hypothyroidism
Elevated TSH (>10) and normal T3/FT4
TSH, LH, hCG, FSH have identical __
alpha units
-beta units account for different biological activity
TSH elevated in ____ hypothyroidism and low in ____ hypothyroidism
primary, secondary
