Thyroid Pathology Flashcards
thyroid pathology is either 1y or 2y- what does this mean?
1y= disease affecting the thyroid gland 2y= hypothalamic/ pituitary disease so no gland pathology
difference between hyperthyroidism and thyrotoxicosis
hyperthyroidism= when there is overproduction of thyroid hormone
thyrotoxicosis= abnormal quantities of thyroid hormone in body
aetiology of hyperthyroidism
excess thyroid stimulation: Grvae’s, hashitoxicosis, tumours, choriocarcinoma
thyroid nodules with autonomous function: toxic nodular goitre, adenoma
rare aetiology: thyroiditis, ectopic thyroid tissue, exogenous (levothryoxine)
s/s of hyperthyroidism
metabolism if OVERactive
- palpitation, anxiety, wt loss/ inc appetite, eye disease (proptosis, lid retraction), thin hair, heat intolerance, sexual dysfunction
ix findings for hyperthyroidism
1y: free T3/T4 inc, low TSH (compensation)
2y: inc T3/T4, normal/high TSH
subclinical finding for hyperthyroidism
dec TSH (<0.1)
mx for hyperthyroidism
antithyroid drugs- carbimazole, PTU (PTU is 1st line in 1st trimester of pregnancy)
BBs, radioiodine therapy (RAI)
main risk with antithyroid drugs?
agranulocytosis- bone marrow suppression causing leukopenia
main risk posed with surgery for thyroid disease
recurrent laryngeal nerve paralysis
thyroid storm is…
emergency of severe hyperthyroidism- resp/cardiac distress, hyperthermia, exaggerated reflex.
mx- ABCs, iodine, PTU, BBs
aetiology of hypothyroidism
1y: goitrous (hashimoto’s, drugs (Lithium/ amiodarone)), non-goitrous (atrophic thyroiditis- poster chemo, congenital etc)
2y: hypothalamus/ pituitary disease, where not enough TSH produced
s/s of hypothyroidism
metabolism is UNDERactive
- coarse hair, dull face, pale/dry skin, fluid retention, cold intolerance, constipation, wt gain/reduced appetite, menorrhagia
ix findings for hypothyroidism
1y: free T3/T4 low, TSH high
2y: free T3/T4 low, TSH normal/low
subclinical clinical findings for hypothyroidism
low TSH
mx for hypothyroidism
levothyroxine (synthetic T4), in elderly give lower 25mg dose
complications of hypothyroidism
myxoedema: severe hypothyroidism
- T2 resp failure, adrenal failure. ECG has signs of arrhythmias
- mx: ABCs, thyroxine, cardiac monitoring
aetiology of thyroiditis
viral, hashimotos
types of thyroditiis
De Quervain’s Thyroiditis, postpartum thyroiditis, drug induced (amiodarone), acute suppurative thyroiditis
s/s of thyroiditis & mx
neck tenderness, fever, viral
mx- BBs, NSAIDs
scintigraphy scan is used for..
thyroiditis- shows low T4 uptake
euthyroid sick syndrome is…
abnormal thyroid function results with no thyroidal illness/ or hypo-pit dysfunction
what is the usually thyroid function test reading for euthyroid
low TSH, low T3/T4
what is Grave’s Disease
AI condition where there are antibodies against TSHr causing hyperthyroidism
T/F: thyroid is 10:1 in females
T !!!
what is the classic triad of Grave’s
goitre + hyperthyroidism, exophthalmos, pretibial myxoedema
Grave’s/ hyperthyroidism often has…
eye disease
- exophthalmos, lid lag
T/F: Grave’s eye disease often associated with alcohol
F: smoking
ix for Grave’s
low TSH, high T3/T4
ABs: TSHr AB*, anti-thyroid peroxidase,
what is hashimotos
leads to gradual failure of thyroid function due to AI destruction of tissue
pathophysiology of Hashi
anti-thyroid ABs > activated CD8+ cells > cytokine mediated cell death
T/F: hashimotos may have a period of transient hyper function of the thyroid
T- known as hashimotos thyrotoxicosis
which ABs would be seen on ix
anti-thyroid peroxidase, antithyroglobulin antibodies
T/F: hashimotos thyroiditis is initially small then grows
F: initially diffusely large > becomes atrophic
a goitre is a…
midline thyroid mass
what are the 2 main types of goitre
diffuse: usually iodine deficiency, T3/T4 normal, TSH high
multi-nodular: evolution from longstanding solitary goitre. may be toxic multi nodular goitre
what is toxic multi nodular goitre?
autonomous nodules producing continuous excessive thyroid hormone causing hyperthyroidism
radioidoine is 1st line for…
relapsed Grave’s or toxic multi nodular goitre
