Ch. 568 - Hyperthyroidism Flashcards
MCC of hyperthyroidism during childhood
Graves disease
Autoimmune disorder with production of thyroid-stimulating Ig resulting in diffuse toxic goiter
Graves disease
T/F Subclinical hyperthyroidism carries a risk of late-life atrial fibrillation
T
T/F Enlargement of thymus, splenomegaly, lymphadenopathy, are well-established findings in Graves disease
T
Cause of proptosis in Graves
Infiltration of retroorbital tissues with lymphocytes and plasma cells; Antibodies
Antibody in Graves
Thyrotropin-receptor antibody (TRSAb)
Action of TRSAb
Bind to receptor for TSH > stimulates cAMP > thyroid hyperplasia and unregulated overproduction of thyroid hormone
T/F Infiltration of retroorbital tissues with lymphocytes and plasma cells is a well-established finding in Graves disease
T
Graves Ophthalmopathy appears to be caused by
Ab against Ag shared by thyroid and eye muscle
Earliest signs in children with Graves
Emotional disturbances accompanied by motor hyperactivity
Characteristics of thyroid gland in Graves
Diffuse goiter, soft with a smooth surface
T/F Afib is a rare complication of Graves disease
T
Hyperthy : Cause of the apical systolic murmur present in some patients
MR, prob from papillary muscle dysfunction
Hyperthy : Reflexes are brisk, especially the return phase of
Achilles reflex
Form of hyperthy: Acute onset hyperthermia, severe tachy, heart failure, restlessness
Thyroid crisis/thyroid storm
T/F Hyperthy may present with extreme listlessness, apathy, cachexia
T, apathetic or masked hyperthy
T/F Measurement of TSI (thyroid-stimulating Ig) and TBII (Thyrotropin binding inhibiting immunoglobulins) is NOT useful in diagnosis of Graves
F, USEFUL
Characteristics of thyroid nodule that is suspicious of Plummer disease
Palpable or T3 preferentially elevated in a hyperthy patient
Initial therapy mostly recommended for patients with hyperthy
Antithyroid drugs > radioiodine or subtotal thyroidectomy
Gaining acceptance as initial treatment in children >10y/o for hyperthy
Radioiodine
Methimazole vs PTU: 10x more potent
Methimazole
Methimazole vs PTU: Much longer serum half-life
Methimazole
Methimazole vs PTU: Heavily protein bound
PTU
Methimazole vs PTU: Lesser abbility to cross placenta
PTU
Methimazole vs PTU: Lesser ability to pass into breastmilk
PTU
Methimazole vs PTU: Preferred during pregnancy and for nursing mothers
PTU
Dose of radioiodine
300Ci/g
Average time course to hypothy in hyperthy patients treated with radioiodine 300Ci/g
11 weeks
T/F Subtotal thyroidectomy is done only after patients has been brought to a euthyroid state
T
Known risk factor for thyroid eye disease and should be avoided or discontinued to avoid progression of eye involvement
Cigarette smoking
