Thyroid and parathyroid disease Flashcards
clinical presentation
- generalized metabolic slowing
- fatigue, weakness
- cold intolerance
- weight gain
- decreased hearing
- depression
- menstrual changes, pubertal delay
- bradycardia
Hypothyroidism
what would present with
- high TSH
- low T4
- normal or low T3
primary hypothyroidism
what would present with
- high TSH
- normal T4
- normal T3
subclinical hypothyroidism
what would present with
- normal or low TSH
- normal or low T4
- normal or low T3
central hypothyroidism (pituitary and hypothalamic disorders)
What antibody tests do you expect to be elevated in Hashimotos thyroiditis
- anti thyroid peroxidase (TPO) antibody
- Anti thyroglobulin (Tg) antibody
What antibody tests do you expect to be elevated in Graves disease
TSH receptor antibody (TRAb)
What is the most common cause of hypothyroidism
hashimoto’s thyroiditis (chronic autoimmune thyroiditis)
is hashimoto’s thyroiditis more common in males or females
F>M 7:1
increase risk of hashimoto’s thyroiditis associated with
- down syndrome
- turners syndrome
hashitoxicosis
transient hyperthyroidism related to early inflammation
precipitating factors to getting hashimoto’s thyroiditis
- stress
- infection
- pregnancy
- iodine intake
- radiation exposure
management of hypothyroid
- synthetic thyroxine (T4) replacement
- leveothyroxine 1.6 mcg/kg/day
- monitoring is important: 6 week f/u to evaluate dosage
definition of subclinical hypothyroidism
- elevated TSH with normal T4
what risks are associated with subclinical hypothyroidism
- CV disease
- nonalcoholic fatty liver
- neuropsychiatric
- miscarriage and low birth weight babies
managment of subclinical hypothyroidism
- repeat TSH and T4 after 1-3 months to confirm dx
- TSH > 10: tx recommended
Hyperthyroidism most commonly affects what patient population
- W > M 5:1
- smokers
- graves: younger women
- toxic nodular goiter: older women
clinical presentation
- exophthalmos, goiter
- weight loss
- tachycardia
- osteoporosis
Hyperthyroidism
what presents with
- Low TSH
- High Free T4 and T3
Hyperthyroidism
what presents with
- Low TSH
- normal Free T4 and T3
subclinical Hyperthyroidism
Hyperthyroidism has what effect on glucose tolerance
- impairs glucose tolerance
What does high uptake and low uptake mean on a 24 hour radioiodine uptake and scan
- high uptake: de novo synthesis of hormone
- low uptake: inflammation/destruction of thyroid gland or extrathyroidal source of thyroid hormone
contraindications to 24 hour radioiodine uptake and scan
- pregnancy
- breast feeding
24 hour radioiodine uptake and scan: HOT -> normal to high radioiodine uptake is consistent with what conditions
- Graves
- hashitoxicosis
- toxic nodular goiter
- iodine induced
24 hour radioiodine uptake and scan: COLD -> near absent radioiodine uptake is consistent with what conditions
- exogenous ingestion of hormone
- thyroiditis
- CA? FNA?
clinical presentation
- lid retraction, stare, Exophthalmos, periorbital edema
- pretibial myxedema
- non nodular goiter
- hyperthyroidism symptoms
graves disease
graves disease is caused by
autoantibodies to thyrotropin receptor (TRAb)
What causes Toxic Multinodular goiter/Toxic adenoma
- diffuse or focal hyperplasia of follicular cells
- likelihood increases with age and iodine deficiency
what is a toxic adenoma
nodule with increased radioiodine uptake
what is a Toxic Multinodular goiter
palpable or defined goiter with multiple nodules
- focal area of increased radioiodine +/- cold spots
- concerning symptoms: cough, dysphagia, dyspnea
medication management of hyperthyroidism
- beta blocker: atenolol
-
thionamides: added to BB for severe dx
- Methimazonle: daily dosing
- Propylthiouracil: preferred in pregnancy
first line treatment for hyperthyroidism
- radioiodine ablation
- typically provided following thionamide
tx of toxic adenoma/MNG
surgery
What are some other names of Subacute thyroiditis
- granulomatous
- de Quervain’s
- gaint cell thyroiditis
Subacute thyroiditis is most common in what patient population
middle aged females
Subacute thyroiditis is associated with what
- URI
clinical presentation
- acute severely painful glandular enlargement (goiter)
- fever, fatigue
- can persist weeks to months
Subacute thyroiditis
how is Subacute thyroiditis diagnosed?
- clinical presentation
- predictable phases: hyperthyroid, euthyroid, hypothyroid, recovery (euthyroid)
- ESR and CRP elevated
treatment of Subacute thyroiditis
- ASA or NSAID
- prednisone if no improvement in several days
thyroid screening is recommended
- not in favor of routine screening
What factors put someone at a higher concern for cancerous thyroid nodules
- kids, men, adults < 30 or > 60
- hx head/neck radiation
- hx hematopoietic stem cell transplant
- fam h/o thyroid ca
Thyroid nodules 3 step approach
- history and physical
- TSH
- thyroid US
high risk patients should have thyroid biopsy if nodule is
- 5-10 mm
- all solid nodules: 5 mm
low risk patients should have thyroid biopsy if nodule is
- solid nodule: 10-15 mm (Hypoechoic: 10 mm)
- mixed cystic and solid: 15-20 mm
when is FNA/biopsy indicated for all patients
- all patients with cervical lymphadenopathy
is FNA/biopsy indicated if nodule is purely cystic
no
Thyroid carcinoma is more common in what patient population? What worsens the prognosis?
- more common in females
- worse prognosis
- < 20 yo
- > 45 yo
- male
Causes of differentiated thyroid CA
- papillary: most common
- follicular
Causes of undifferentiated thyroid CA
- anaplastic
- poor prognosis
Causes of familial thyroid CA
- medullary
- test for RET mutations as a genetic marker
Management of thyroid ca
- surgery
- radioiodine ablation (follows surgery)
- thyroid hormone suppression
- levothyroxine
Hypoparathyroidism causes
-
acquired
- usually occurs post-thyroidectomy
- rarely, neck irradation
- autoimmune
- congenital
clinical presentation
- tetany
- sz
- weakness
- heart failure, hypotension, arrhythmia, prolonged QT interval
- papilledemia
acute Hypoparathyroidism
what specialized tests should you do when assessing for Hypoparathyroidism
- Trousseau’s sign
- Chvostek’s sign
clinical presentation
- ectopic calcifications
- parkinsonism
- dementia
- cataracts
- dry, coarse skin
- impaired dentition
- brittle nails
- hair loss
- renal stones, renal failure
chronic Hypoparathyroidism
what lab results would you expect in Hypoparathyroidism
- serum Ca2+
- serum phosphate
- urinary Ca2+
- alk phos
- PTH
- magnesium
- serum Ca2+: Low
- serum phosphate: High
- urinary Ca2+: Low
- alk phos: Nml
- PTH: Low
- magnesium: often elevated
tx for acute, emergent hypoparathyroidism
- IV calcium gluconate
treatment for chronic hypoparathyroidism
- calcium and vit D supplementation
most common cause of primary hyperparathyroidism
parathyroid adenoma
causes of secondary hyperparathyroidism
- chronic renal failure
- vit D deficiency
- renal osteodystrophy
clinical presentation
- asymptomatic hypercalcemia
-
bones, stones, abdominal moans, psychiatric groans”
- fragile bones
- kidney stones, DI
- abd pain, N/V
- psychosis, depression
hyperparathyroidism
what lab results would you expect in secondary hyperparathyroidism
- serum calcium
- serum phosphate
- PTH
- serum calcium: low
- serum phosphate
- high (renal)
- low (Vit D)
- PTH: high
what diagnostics would you get to assess for hyperparathyroidism
- DEXA scan
- kidney function
- 24 hr urine
- parathyroid US
- sestabibi parahyroid scan (radioactive) with CT scan
definitive tx of hyperparathyroidism
- surgery: parathyroidectomy
- may be hypocalcemic post-op
conservative tx of hyperparathyroidism
- physical activity
- fluids
- avoid lithium and HCTZ
- restrict Ca2+ intake
medical management of primary hyperparathyroidism
- IV bisphosphonates
- can temporarily decrease hypercalcemia and treat bone pain
- pamidronate
- zoledronic acid
- can temporarily decrease hypercalcemia and treat bone pain
medical management of secondary or tertiary hyperparathyroidism
- phosphate binders: calcium carbonate or calcium acetate
- calcimimetics
- vitamin D
