internal medicine 1 endocrinology Flashcards
causes hypopituitarism?
- congenital: prader willi (del15) –> hypogonadism + Kallman syndrome (no neural migrations thus no GnRH –>no LH nor FSH –> hypogonadism + Empty sella syndrome
- aquired
- trauma, surgery, radiation damaging pituitary gland
- tumors: adenoma or metastasis
- infection: toxoplasma
- Sheenhan post partum necrosis (no bloodsupply thus necrosis of pituitary) –> no postpartum lactation, loss of pubic hair
hormones of anterior pituitary?
GH, FSH/LH, ACTH, TSH, PRL
hormones of posterior pituitary (neurohypophysis)?
ADH, oxytocin
examples of hyperfunctions of anterior pituitary?
- Prolactinoma –> galactorrhea, amenorrhea, infertility, bipolar hemianopsia
- cushings disease
- acromegaly (adult) giantism (kids)
diabetes insipidus 2 types?
- central type: ADH deficiency due to eg. post.pituitary tumor
- nephrogenic type (more common): no ADH receptors in kidney
symptoms of diabetes insipidus?
polyuria, polydipsia (crave cold water)
dx of diabetes insipidus?
Water deprivation test:
aim: differentiate from psychogenic polydipsia
measure urine density –> no water for 8 h –> measure urine density again, positive if low urine density
psycogenic if high urine density
desmopressin test (ADH analog)
aim: differentiate nephrogenic from central
central: respond to test by increase H2O absorption from kidney
nephrogenic: no respons to test (bc. no ADH receptors doesnt matter if we give ADH)
SIADH meaning?
syndrome of inappropriate anti-diuretic hormone:
high levels of ADH in blood
causes, symptoms, tx of SIADH
causes examples: ADH producing small cell lung carcinoma, opioids, stroke
symptoms: low urine output, increased serum hypoosmolarity, hyponatremia –> nausea, vomit
tx: dont drink so much water, demeclocycline
causes of hypothyroidism?
- primary hypothyroidsm
- Hashimotos autoimmune thyroiditis #1
- surgical removal, viral infection, congenital - secondary hypothyroidism
- damaged ant. pituitary (no TRH no TSH)
symptoms of hypothyroidism?
decresed BMR thus weight gain, fatigue, intolerance to cold, goiter/struma, muscle ache and weakness, bradycardia, myxedema (accumulations of glycosaminoglycans in skin and soft tissue –> deepening of voice and large toung)
3 stages of Hashimoto?
- initially hyperthyroidism due to ANTI-TG-AB causing damage of thyroid follicles thus release of thyroid hormones.
- symptoms of euthyroid when decrease of hormone cc
- final hypothyroidism
dx of hypothyroidism?
elevated TSH, clinical symptoms, autoabs
ANTI-TG-AB (thyroglobulin)
ANTI-TPO-AB (thyroid peroxidase)
hypothyroidism and infertility connection?
50% of patients with hypothyroidism have prolactinemia bc. TRH increase TSH and PRL
PRL cause failure to sustain the fertilized egg thus loss of early pregnancy (infertility)
hyperthyroidism causes?
- Graves #1 (autoimmune- ANTI-TSHreceptor-AB) TRAB
- Destructive thyroiditis aka De Quervain (post viral infection)
- Toxic (hormone producing) adenoma
- Thyroid hormone overdose
symptoms of hyperthyroidism?
increased BMR thus weight loss, exophthalmos (bulging of eyes due to retrobulbar CT edema)–> swelling of extraocular muscles –> compress optic n. –> vision loss, struma/goiter (in both hypo and hyper)
3 categories of thyroiditis?
acute, subacute, chronic
example of acute thyroiditis?
Acute infectious thyroiditis due to eg. E.coli, severe neck pain radiating to ear
(non-infectious due to eg. radiotherapy as side effect due to thyroid malignancy)
example of subacute thyroiditis?
De Guervains (subacute granulomatous thyroiditis)
post viralinfection eg. adenovirus “cold” causing granuloma formation in thyroid
sym: painful dysphagia, fever neckpain after URT infection
-initially hyperthyroidism when gland is damaged by granuloma reaction and thus hormones released into blood, few (15%) become hypothyroid after inflammation decrease.
Note: importance to diff. from Graves since this form of hyperthyroidism is self-limited 6 w (vs. Graves: radioiodine tx)
example of chronic thyroiditis?
Hashimotos autoimmune thyroiditis
-ANTI-TPO-AB
-ANTI-TG-AB
destruction of thyroid gland, inflammatory infiltrade, CD8+ cells kill thyroid cells, B cells produces the ABs
Goiter=struma meaning?
painless thyroid enlargement
thyroid malignancies?
- follicular adenoma
- papillary carcinoma #1
- follicular carcinoma
- anaplastic carcinoma
- thyroid medullary carcinoma (c-cells)
follicular adenoma characteristics?
solitary, non-funtional thus “cold nodule” with nuclear medicine
- may progress to carcinoma
- if TSH R. mutation –> increase thyroid hormones –> functional toxic adenoma “hot nodule” (rarley become malignant)
dx. UL
papillary carinoma characteristics?
1
- any age, non functional
- MAP kinase pathway overactivated
- painless neckmass
- 50% metastasize to cervical LN + lung + bone
- prognosis: 90% survive 10 yrs
follicular carcinoma characteristics?
- women 50+
- painless neckmass
- NO cervical LN metastasis (how to differ from papillary carcinoma) spread to blood.
- invasive of thyroid capsule (how to differ from follicular adenoma)
anaplastic carcinoma characteristics?
- oldies 65+
- very agressive, almost 100% mortality, death in 1 year
- p53 mutation
thyroid medullary carcinoma characteristics?
- origin from parafollicular C cells (of medulla that make calcitonin that decrease calcium by inc. renal extretion)
- MEN2 (RET oncogen) 30% but mainly sporadic 70%
- prognosis: median survival 5 yrs (aggressive with quickly metastasis)
- no hypocalcemia even if increased calcitonin (tumor marker) bc. the tissue get resistant to calcitonin
symptoms: painless neckmass, compressionsymptoms:hoarsness,dyspnea,dysphagia,cough
Cushing´s syndrome def?
glucocorticoid excess in the blood (exogenous or endogenous) that causes a group of symptoms
symptoms cushings syndrom?
- moon face
- central obesity (fat belly skinny legs)
- red stria on abdomen
- buffalo hump = fat deposit on back of neck
- hyperpigmentation (incr. ACTH –> incr. alpha-MSH –> hyperpigm.)
- HTN (if too high glucocorticoid cc they also stimulate aldosterone receptor –> H2O retention –> incr. BP)
- incr. glucose –> DM
cushings disease
cause cushings syndrome due to:
ACTH producing pituitary adenoma or hypothalamic CRH secretion –> inr. ACTH
dx and differentiation of cushings syndrome and disease?
Dextrametasone test (cortisol analogue) - LOW dose administration: cortisol is suppressed --> Cushings syndrome
-HIGH dose administration:
ACTH is suppressed by negative feedback thus cortisol decr. in blood –> Cushings disease
(ectopic ACTH producing adenomas cannot be suppressed)
other test of cushings syndrome:
- 24 h urine cortisol level will be increased
- late night salivary cortisol level will be increased
Primary hyperaldosteronism AKA CONN’s SYNDROME ?
high aldosterone level and LOW renin
triad symptoms: HTN, hypokalemia, HYPERnatremia + metabolic alkalosis
cause:
- aldosterone producing adenoma (unilateral)
- bilateral adrenal hyperplasia
- carcinoma rare
tx:
- if adenoma/carcinoma: surgical removal
- hyperplasia: sporonolactone (aldosterone receptor antagonist)