Endocrinology Flashcards
short stature
2SD below mean ht
normal variant short stature- short but growing at norm velocity
pathologic short statue-short and suboptimal growth
if grow 2in/y btw 3-puberty= no endocrinopathy or underlying pathologic D
hypopituitarism
suspect when hx of hypoglycemia, prolong jaundice, cryptorchidism, microphallus
normal variant short stature
familiar short stature: below 2SD, normal bone age and onset of puberty
constitutional short stature- >2SD, delayed bone age and late onset of puberty
disproportionate short stature
rickets (frontal bossing, bowed legs, low serum phosphorus, high serum alkaline phosphatase) and skeletal dysplasias
proportionate short stature
in utero: enviro, chromo (down, turner), genetic (prayer will,), viral (CMV)
postnatal- malnutirtion,psych, organ system disease
evaluate short stature
Lab: cbc, ESR, T2, BMP, IGF-1 (indirect test for GH),, chromosome analysis for turner’s
radiographic study: bone age, pituitary gland - craniopharyngioma- distortion of sella truck and suprasellar ca
GH deficinecy
uncommon.
P: prolong neonatal jaundice, hypoglycemia, cherubic facies, central obesity, microphallus, crytorchidism, midline defects, growth curve show poor velocity
causes: craniopharyngioma if kid older than 5yo not growing 2in/y
bone age
endocinopathies that cause growth stunt
all bone age
female puberty
onset btw 7-13yo
male puberty
9-14yo. first sign is testibular enlargement
precocious puberty
girls: breast dev or pubic hair bf 7yo or monarch bf 9yo. premature the larch at 2yo and adrenarch at 5 w/o the other needs no workup.
boy: testicular changes,penile enlarge, pubic/axillary hair bf 9yo
isosexual prevovious puberty = central precocious puberty (CCP
norm dev at hearier age. females tend to be idiopathic. males organic so need MRI head for all cases. Can be caused by hydrocephalus, CNS infections, hypothalamic hamartomas, atrocity, gliomas, head trauma, benign cerebral palsy, hypothyroidism
dx: FSH, LH, sex steroid elevated. GNRH sitmulation test(assess activation of HPGA axis. if cause incr LH, likely LH.
peripheral prevocious puberty (PPP)= heterosexual gonadotropin indep puberty
indeed of HPGA axis due to peripheral sex steroid (Not FSH or LH) production. flat response on GnRH stimulation bc HPGA axis not activated
boy- feminization, pubic hair, no testicular enlargement bc no incr in FSH
girls- variation or breast dev
etio: exogenous sex steroid, gonadal tumor, adrenal tumor, hyperplasia of adrenal gland
boys with testicular enlargment:
1) McCune -Albright syndrome- bony changes and coast of maine cafe au last spots. endocrinopathies
2) testotoxicosis- enlarge b/l
3) betal HCG secreting tumor- only in boys
same evils CPP
delayed puberty
boy: no testicular enlargement by 14 Girl- no breast tissue by 13 or monarch by 14 2 types 1) hypogonadotropic hypogonadism: 2) hypergonadotropic hypogonandism:
hypogonadotropic hypoganadism
inactivity of hypothalamus and pituitary. flat GnRH stimulation test
etio: constitutional delay of puberty: usually fx, associated with constitutional delay of growth. immature hypothalamus. chronic disease like anorexia, IBD, HF, RF. hypopituitarism, primary hypothyroidism, prolactinoma, genetic (klaxon, prader will)
hypergonadotorpic hypogonadism
end organ dysfunction. high FSH, LH, low testosterone estradiol
boys: klinefelter
girls- turner
AI- hashimotot thyroiditis, addison’s
ambiguous genitalia male
1) inborn error in testosterone synthesis:
2) gonadal intersex: internal structures of combo of M and F: mixed gonadal dysgenesis (mosaicism 45XO/46XY, vas def and fallopian tubes). true hermaphroditism
3) partial androgen insensitivity- defective binding- x linked. testicular feminization syndrome has complete insensitivity and present as normal phenotypic female with 46XY.
ambiguous genitalia in virilized female
1) CAH caused by 21 hydroxyls deficiency is most common pseudohermaphroditism. suggested by incr BP
2) virilizing drug taken by mom in preg
3) virilizing tmor in mom while preg
decr BP suggest adrenal insuff.
cortisol def sx
anorezia, weakness, hyponatremia, hypotension, incr pigmentation over healing scars
aldosterone def
FTT, salt craving, hyponatremia, hyperkalemia
primary adrenal insufficinecy
addison’s, CAH, adrenoleukodystrophy.
secondary adrenal insuf
ACTH or CRH lvl problem. since minerocorticoids not reg by them, no aldosterone def and normal seem K.
etio- most common is iatrogenic- glucocorticoids >2wk suppress hypothalamus
congenital adrenal hyperplasia (CAH)
AR. most common cause of ambiguous genitalia with unpalpable gonads.
enzyme def lead to less cortisol or aldosterone and build up of precursors that is shunted into androgen production.
3 types of 21-H hydroxyls def
1) classic salt wasting: cortisol and aldo def= FFT, vomit, electrolyte abn
2) simple virilizing CAH, only cortisol def. tall, adv bone age, pubic hair, penile enlargement, girl virile. no electrolyte ab
3) nonclassic CAH: late onset with mild cortisol def no aldo def.
111 beta hydroxylase def- hypertensive, and hypokalemic
3beta hydroxyteroid deH def: salt wasting crises, cotisol def, ambiguous genitalia and early black in all three adrenal steroid pthwy.
CAH workup
1) incr 17- hydroxyprotestone (17OHP) in 21 hydroxylase def
2) incr specific compound S in 11 beta hydroxylase def
3) incr DHEA and 17 hydroxypregnenolone in 3 beta hydroxysteroid deH def
4) low Na, high K
CAH management
cortisone admin to suppress ACTH so less excess androgen production = don’t interfere with proper growth
mineralcorticoid replacement- fluorocortisol
f/u
glucocorticoid excess
poor growth with delay bone age, central obesity, moon facies, nuchal fat pad, easy bruising, purple striae, HTN, glu intolerance
hypercortisolism etio: iatrogenic -most common, cushings syndrome (adrenal tumor), cushing disease (excessive ACTH production -pituitary tumor,)
labs: 24hr urine cortisol elevated, dex supression test- no suppression,
DMI
95% have HLA hypolotype DR3 or DR4
viral infection,
AI: islet cell ab in 85%.
clinical: girsl have protracted monilial vulvovagininitis
adolescent present in puberty when GH and sex steroid antagonize insulin action
dx- hyperglycemia >200 with polyuria/dipsia, wt loss, or nocturne
somogyi phenomenon
evening dose too high so body make epi and glucagon to counter in morning resulting in hyperglycemia induced by insulin. tx by lowering insulin
DKA
mild in DM2. can be severe in DM1. hyperglycemia >300 with coterie and serum bicarb
acanthosis nigricans
hyper pig skin at neck and ancillary folds. in DM2
congenital hypothyroidism etio
most common metabolic D
etio
1) thyroid dysgenesis: 90%. 2/3 aplasia or hypoplasia. 1/3 exctopic- base of tongue to mid chest
2) thyroid dyshormogenesis- inborn errorAR> often goiter and sensorineural hearing loss
3) PTU use in mom cause transit hypothyroidism in newborn
4) materal Ai thyroid disease- transit hypothyroidism
congenital hypothyroidism P
asx initially hx: of jaundice and poor feeding lthargy and constipation PE: large anterior and posterior fontanelle, protruding tongue, umbilical hernia, myxedema, mottled skin, hypothermia, delay neurodev (TH is essenial for 1st 2y of brain dev), poor growth Labs: normal NH3, normal glu
hashimoto’s disease
chronic lymphocytic thyroiditis (CLT) that cause follicular fibrosis and atrophy and follicular hyperplasia.
most common acquired hypothyroidism w/wo goiter
more in girls
P: variable. asx, goiter, short, transient hyperthyroidism-hashitoxicosis,
incr TSH
first sign of thyroid failure
hyperthyroidism
lid lag and exophthalmos, enlarge thyroid gland that is smooth, tachycardia, palpitations, warm and flushed skin. if see vitiligo or alopecia there may be other AI polyendocrinopathis like addison and DM. nervousness, fine tremors, fatigue, delay monarch and gynescomastia in boys
grave’s
incr T3, T4 with suppressed TSH bc TSI
tx: PTU and methimazole
PTH
releases ca and phosphorus from bone. excrete phosphorus through kidney. reabsorption of ca and bicarb
25 OH vit D
converted into 1,25 OH D in kidney which stimulate Ca absorption in GI
hypocalcemia: etio, labs
serum Ca 4yo: hypoPTH, digeorge, hyperphosphatemia (from excessive phosphate intake or uremia)
3) childhood hypocalcemia: hypoPTH, pseudohypoPTH (PTH resistance, AD D, short, dev delay, incr PTH), hypomagnesemia (malabsorptive disease), it D def (low phosphorus dev)
labs: serum Ca, phosphorus, mg, ECG (prolong QT), PTH, Vit D, radiograph of wrist of knee to eval for rickets
tetany
1) carpopedal spasm- hypocalcemia cause peripheral MN excitement, painful spasm of wrist and ankles
2) laryngospasm
3) paresthesias
pseudohypocalcemia
de to low albumin lvl. in nephrotic syndrome
hypocalcemia tx
mild asx don’t need tx.
newborn with lvl
Rickets etio
cause by VitD def. def mineralization of growing bone w/ normal bone matrix
predisposed by: exclusive breast fed, fad diet, anticonvulsants, renal/hepatic failure
etio: vit D def, GI D- fat malabsorption, nutritional, defective vit D metabolism,
1) vit D dep rickets -rare= enzume def 1 alpha hydroxylase vita D results in no 1,25 OH D. present with incr PTH, low it D, low Ca, low P, incr alkaline phosphatase
2) vit D résistent rickets- familial hpophosphatemia: most common type of rickets. x-linked dom. renal tubular phosphorus leak. low serum P lvl. normal ca. bowl legs no tetany. tx with P sup and 1,25 D analogs
3) ocogenous rickets- in pt with bone pain or myopathy
rickets P
occu
diabetes insipidus
inability to maximally conc urine bc low ADH (central DI) or unresponsive to ADH (nephrogenic DI
P: nocturia, enuresis, poort wt gain, polydipsisa/uria
dx: if thirst intact +access to water then electrolytes normal. otherwise hyponatremic dehydration with inappropriately dilute urine in face of incr serum Na and incr serum osmolarity. early morning urine SG >1.018 ro DI. water deprivation test - rise serum osmolarity despite urine output, low osmo, MRI head, bone scan- langerhans
central DI
AI (ab target ADH producing cells), trauma and hypoxic ischemic brain injury, hypothalamic tumor, langerhans cell histiocytosis (25%), granulomatous disease (tb, sarcoidosis), vascular (aneurysm), genetic (AD)
tx: DDAVP (synthetic ADH)
nephrogenic DI
x linked R. non-responsive to ADH
hypoglycemia
definition:
persistent neonatal hypoglycemia
last >3d.
1) hyperinsulinism due to islet cell hyperplasia (nesidioblastosis), beck with-wiedemann syndrome. LGA and present with visceromegaly, hemihypertorphy, macroglossia, umbilical hernia, distinctive ear crease
2) hereditary defect in carbohydrate meta- glycogen storage disase type I, aa meta (maple syrup)
3) hormone def: GH def or cortisol def. suspect congeital hypopituitarism in neonate who present with hypoglycemia, microphallus, midline defect ~ cleft palate
hypoglycemia in infancy and kids
uncommon. DD
1) ketotic hypoglycemia- 1-6yo. in late morning with coterie and low insulin bc can’t adapt to fasting state. thin and hypoglycemic after infection
2) ingestions-alcohol, oral hypoglycemic agents
3) inborn erros of metabosim
4) hyperinsulinism
