Thyroid Flashcards
De Quervains
Hyperthyroidism Self limiting Viral Painful goitre Temp High ESR Low isotope uptake on scan Tx - NSAIDs
Grave’s Disease
hyperthyroidism
> females
40–60yrs (younger if maternal family history
Increased production thyroid hormones, enlarge thyroid
Signs Grave’s
Eye disease exophthalmos, ophthalmoplegia.
Pretibial myxoedema: oedematous swellings above lateral malleoli
Thyroid acropachy: extreme manifestation, with
clubbing, painful finger and toe swelling, and periosteal reaction in limb bones.
Graves autoantibodies
TSH receptor stimulating antibodies (90%)
anti-TPO antibodies (75%)
Toxic multinodular goitre:
elderly
in iodine-deficient areas
compressive symptoms > surgery
Toxic adenoma
solitary nodule producing T3
Hot nodule on isotope scan
Ectopic thyroid tissue
Metastatic follicular thyroid cancer
Struma ovarii: ovarian teratoma with thyroid tissue.
Treatment hyperthyroidism
B-blockers
Carbimazole
SE: agranulocytosis (neutrophils, can lead to dangerous sepsis; rare (0.03%))
Radioiodine
Thyroidectomy - recurrent laryngeal nerve (hoarse
voice) and hypoparathyroidism
Hypothyroidism associations
Autoimune - T1DM, Addison’s, PA
Turner’s and Down’s syndromes
Cystic fibrosis,
PBC
OHSS
POEMS syndrome—
poly neuropathy, organomegaly, endocrinopathy, m-protein band (plasmacytoma) +
skin pigmentation/tethering
Genetic:
Dyshormonogenesis: genetic (often autosomal
recessive) defect in hormone synthesis, eg Pendred’s syndrome (with deafness):
there is increased uptake on isotope scan, which is displaced by potassium perchlorate
Hashimoto’s thyroiditis:
Goitre due to lymphocytic and plasma cell infiltration.
> women aged 60–70yrs
May be hypothyroid /euthyroid; rarely initial period of hyperthyroid (‘Hashitoxicosis’).
Autoantibody titres are very high.
Ass w MALT lymphoma
Complications of hypothyroidism Pregnancy
Eclampsia, anaemia, prematurity, low birthweight, stillbirth, PPH.
Treatment hypothyroidism
Thyroxine - 50-100 ug, adjust 6/52
25 ug if elderly/ CV disease
Papillary thyroid ca
60%
Often younger patients.
Spread: lymph nodes & lung (jugulodigastric
node metastasis is the so-called lateral aberrant thyroid).
Treatment:
total thyroidectomy to remove non-obvious tumour ± node excision ± radioiodine to ablate
residual cells.
Give thyroxine to suppress TSH.
Follicular
≤25%
Occur in middle-age & spreads early via blood (bone, lungs).
Well-differentiated- total thyroidectomy + T4 suppression + radioiodine ablation.
Medullary
(5%) Sporadic (80%) or part of MEN May produce calcitonin Perform a phaeochromocytoma screen pre-op. : thyroidectomy + node clearance. External beam radio therapy should be considered to prevent regional recurrence.
Lymphoma
5%
≈3:1
May present with stridor or dysphagia.
Do full staging pre-treatment (chemoradiotherapy). Assess histology for mucosa-associated
lymphoid tissue (MALT) origin (associated with a good prognosis)
Multinodular goitre
most common goitre in the UK.
usually euthyroid, but may become hyperthyroid (‘toxic’). MNG may be retro- or substernal.
Hypothyroidism /malignancy within MNG are rare. Plummer’s disease is hyperthyroidism with a single toxic nodule (uncommon).
Who to screen for TFTs?
AF Hyperlipidaemia Diabetes annual review Pregnancy - T1DM first trimester and post Amioderone/ lithium Down's/ turners/ Addison's yearly
Most common cause of hypothyroidism in kids
autoimmune thyroiditis
Iodine def in developing world
Riedel’s thyroiditis
rare hypothyroidism dense fibrous tissue replacing the normal thyroid parenchyma hard, fixed, painless goitre middle-aged women ass w retroperitoneal fibrosis.
MEN 1
PPP Parathyroid, Pituitary, Pancreas \+ adrenal, thyroid MEN1 gene most common presentation- hypercalcaemia
MEN 2a
Medullary thyroid
2Ps
Parathyroid, pheochromocytoma
RET oncogene
MEN 2b
Medullary cancer
1 P - phaechromocytoma
RET oncogene
SE thyroxine
hyperthyroidism: due to over treatment
reduced BMD
worsening of angina
AF
Thyroxine interactions
Iron, calcium (absorption of levo reduced, 4 hrs apart)
