Endo Flashcards
Critical time for intervening to prevent external ambiguous genitalia and what do you treat with?
Before 8-12 weeks when androgen exposure will have significant virilization w/ ambiguity. Treat with maternal dexamethasone which will suppress ACTH secretion in fetal pituitary
Screen for CAH?
What does it show (increased in what?)
17 -OH Progesterone increased in
21 hydroxylase def CAH
Define primary adrenal insuff?
affects adrenal gland itself (vs secondary: pituitary, tertiary: hypothal)
Layers of adrenal gland and what they make?
GFR: Glomerulosa (Aldo, Outer) –> Fasciculata (GC, middle) –> Reticularis (Deep, catecholamines)
Hormone responsible for heralding adrenarche from adrenal gland?
Catecholamines with redevelopment in Reticularis
CAH causing hypertension?
11 hydroxylase def
distinguish Cushing from obesity
Cushing will have decreased growth velocity, obesity will have incr growth velocity
Sx of glucocorticoid withdrawal / insuff
What about salt issues?
malaise, anorexia, HA, lethargy, n/v, BP drop b/c of catecholamine effect BUT no salt issues because glomerulosa function is regulated by RAS
Tx of adrenal crisis?
fluid bolus with no K Stress dose hydrocortisone 80mg/m2 or Dex 3mg Infant: 25mg IV Child: < 12: 50mg IV Adol: 100mg IV
3Ps of pheo?
Paroxysms of HA/BP, etc
Palpitations
Perspiration/diaphoresis
Pheo syndrome causes
MEN 2a and 2b, VHL, NF
MEN 2a vs 2b
same and diff
2a: parathyroid
2b: marfinoid, neuromas
Both with pheo and thyroid (the PH and TH)
lab features of pseudohypoparathyroid and what is the cause?
very high PTH, but low Ca, high phos (as though you have low PTH). Receptor defect
whats the diagnosis: facial wasting, v shaped upper lip, constipation, fTT, normal CK, cataracts, arrhythmias, hypogonadism, ID, later with DM and adrenocortical insuff?
Myotonic dystrophy (mom hand shake dx)
Think of this if you see microphallus and hypoglycemia, and do what test?
Panhypopit, do MRI” to look for septooptic dysplasia
Turner gets what infx?
recurrent otitis media
% mosaic for Turner
15%
additional system issues in Turner?
renal: horseshoe, pelvic, UPJ obstrx
early menopause
thyroid
bone (GH levels normal though)
large persistent fontanelle, frontal bossing, triangular face, asymmetry/hemihypertrophy, 5th finger issue, short short short
Bonus: genetic cause?
Silver Russell
10% maternal uniparental disomy chr 7
what is hypochondroplasia?
milder than achondroplasia with frontal bossing, stocky build
non salt wasting CAH?
11 beta hydroxylase def –> get HTN
emotional deprivation looks like what endocrinopathy issue
hypopituit
how to prevent insulin lipoatrophy
rotate insulin sites
lab testing for Cushing syndrome
urinary free cortisol is very high as screening, definitive dx with dexameth stim test
CBC abnormalities in cushing?
polycythemia, eosinphilia, lymphopenia
Ddx of hyperthyroidism from graves vs exogenous thyroid H
measure thyroglobulin
do neonatal congenital hypothyroid have goiter?
No. 90% from dysplastic thyroid
don’t mix thyroxin tabs with what?
iron / soy formula
prolonged jaundice in newborn should make you think of what
hypothyroidism
alpha L iduronidase on chr 4?
Hurler
three cancers in Beckwith Weidemann
Wilm, adrenocortical carcinoma, hepatoblastoma
why hypoglycemia in Beckwith Weidemann and what is distinguishing feature?
pancreastic beta cell hyperplasia NO ketones (like fatty acid oxidation defect)
AEDs causing Vit D def
PB, dilantin
explain how acid / base status influences serum calcium?
with acidosis - low pH - low bound Ca, high ical
with alkalosis - hi pH - hi bound Ca, low ical
major PTH effects on bone, kidney, gut
bone: cal/phos release
gut: absorb Ca (both PTH and calcitriol)
kidney: reabsorb Ca, waste phos AND incr vit D/calcitriol
Overall: incr Ca, decr Phos, incr calcitriol
what causes increase PTH?
- Hypocalcemia
- hyperphosphatemia
- calcitriol def
hypocalcemia causes what?
neuromusc instability: jerks, twitching, exagg startle, seizures
apnea, vomiting, laryngospasm
Chvostek sign
Elvis sign
Risk factors for early onset hypocal
Prognosis
prematurity, VLBW, maternal DM (decr PTH), perinatal asphyxia (hyperphos from injured tissue), maternal hyperparathyroid (PTH suppressed in baby)
Usu transient 1-2wk
Think of what if you see later (after 1 week) hypocalcemia in newborn? 3 major causes
- hypomagnesemia (PTH resistant)
- too much phosphate (now rare)
- DIGEORGE (hypoparathyroid)
maternally transmitted mutation causing pseudohypoparathyroidism? Dx?
genetic imprinting: GNAS1 (maternally trm mutation), causes albright’s hereditary osteodystrophy
What is pseudo-pseudohypoparathyroidism?
Paternally transmitted GNAS1 mutation, causes physical findings of Albright’s hereditary osteodystrophy (round face, short, obese, delayed) but with normal levels of everything
Dx if very low urine calcium excretion, but hypercalcemia?
cause?
Familial Hypocalciuric hypercalcemia (autosomal dominant and benign)
-inactivating defect in calcium sensing receptor gene
Cause and prognosis of hypercalcemia in Williams
primary hypercalcemia that is typically transient
Normal PTH, Vit D
what vitamin issues can give hypercalcemia?
toxicity of Vit A or D
REq vit D now in newborns?
400 IU/d
Dx?
1, 25 OH Vit D low but normal 25-OH vit D with early severe hypocalcemia and early skeletal manifestations.
Treatment?
1-alpha hydroxylase deficiency
chromosome 12q14
Tx w/ calcitriol
when do signs of congenital hypothyroidism present?
at 5 wks (before that they are protected by maternal thyroid)
initial management of congenital vs acquired hypothyroid
congenital: start high with 10-15mcg/kg/day and monitor often q2 mos in first 2 yrs
acquired: 0.024-0.05mg daily, then increase by 0.0125 until TSH normalizes
sick euthyroid vs hypothyroid
TSH will be high in hyperthyroid and normal or low in sick euthyroid. rT3 also distinguishes: low in hypothyroid, high in sick.
antithyroid meds / dose
s/e?
PTU 5-10mg/kg divided TID (RARELY used - liver tox)
Methimazole 0.5-1mg/kg/day
s/e: can cause lupus, hepatic tox, agranulocytosis
Pathophys of neonatal graves?
BB, prednisone, Lugol
Give methimazole and l-thyroxin
need 6 mos treatment
Passage of mom’s Abs… even if she was treated, she may have abs.
Presentation, Dx and
Treatment of subacute thyroiditis
painful swelling of thyroid, expect high T4 very low TSH
Decreased radioactive iodide uptake scan
Tx w/ BB, ASA, glucocorticoid which decr thyroid hormone
parathyroid, pituitary, pancreatic adenomas
Dx?
MEN1
medullary thyroid carcinoma, pheo, parathyroid adenoma
Transmission
Men 2A (AD)
medullary thyroid carcinoma, pheo, mucosal neuromas, intestinal neuromas, marfanoid
Transmission
MEN 2b (sporadic mutation)
differentiate Graves and subacute thyroiditis based on radioactive iodide uptake scan?
Graves: incr uptake
subacute thyroiditis: decr uptake
salt wasting vs simple virilizing form of early onset (Classic) CAH 21-OH Def
virilizing only < 1 % enzyme
suspect this in pt w/ premature pubarche/adrenarche, severe acne/hirsutism, menstrual abnormality, female pattern baldness?
mechanism of defect?
Late onset CAH (30 - 50%enzyme activity 21-OH Def)
volume depletion, hypoNa, hyperKalemia, poor cardiac function/shock?
Adrenal crisis!
CAH and height?
tall children, short adults
LAb finding in eval of CAH in classic vs nonclassic
classic: 17OHP >10,000
late/non-classic: 17OHP >1,000
hyperpigmentation, FTT, hypoglycemia, seizures
Dx? pathophys?
ACTH receptor defect in Familial Glucocorticoid Deficiency
adrenal insuff, achalasia, alacrima, autonomic abnormality
Dx?
Allgrove (As!) AR loss of AAAS gene
Defect in secondary adrenal insuff and what distinguishes it from primary
Anterior pituitary dysfunction, so mineralocorticoid is fine and no salt wasting
Symptoms unique to primary adrenal insuff (3)
- salt craving and hyperk / very low Na
- increased pigmentation
- Increased ACTH / Incr K, Decreased Aldo
maintenance glucocorticoid and mineralocorticoid in CAH
glucocort: 10-15mg/m2 div BID/TID
mineralocort: florinef 0.5-2mg daily (infants get salt tabs 1-4g)
Management of CAH stress dosing for surgery
x3 maintenance GC nt prior
Give IV 30-100mg/m2 hydrocort on call to OR
post surg: continue 100mg/m2/d hydrocort q6 x 24 hrs
back to maintenance 203 days
non exogenous Cushing in kids likely causes (2)
young kids: adrenal adenoma
older kids: pituitary adenoma (Cushing disease: ACTH production in kids >7y)
Eval for Cushings? (4)
midnight salivary cortisol
24hr urinary free cortisol
overnight dexameth suppression
high androgens
what is responsible for formation of male external genitals in XY?
What is responsible for regression of the female internal duct structures? Produced by?
presence of androgens makes external genitalia
Mullerian inhibiting factor –> regression of female internal duct
Produced by male testes
XY infant with cliteromegaly and palpable masses in labial folds
Dx?
Test for what?
Androgen insensitivity / male pseudohermaphroditism
5-alpha reductase deficiency and 17 ketosteroid reductase deficiency should be ruled out.
what does 5-alpha reductase def cause?
what does 17-ketosteroid reductase def casue?
- 5-alpha: can’t reduce testosterone to DHT
2. 17-keto: can’t convert androstenedione to testost
what do the Müllerian ducts (paramesonephric) ducts become?
uterus, cervix, upper vagina, tubes
normal looking vagina, and testes in inguinal canal
What other internal structures?
testicular feminization / androgen insens
Due to MIF, there is NO uterus or ovaries, so vagina ends in blind pouch
micropenis, hypoglycemia, decr TSH, decr GH
Syndromes assoc?
Do what additional work up?
panhypopit Prader willi Kallmann Septo optic dysplasia Renal function
excessive scrotal pigmentation, shock, septic picture in MALE baby?
CAH: males DON’T have ambiguous genitalia
girl baby with shock, ruggated labia, clitoral hypertrophy?
CAH: female w/ ambiguous genitalia
21-hydroxylase is needed to produce what hormones? What buids?
Cortisol and Aldo.
Testosterone builds
prenatal screening of CAH?
molecular genetic testing of fetal cells
pharmacologic treatment of ccongenital CAH
hydrocortisone hemisuccinate: also has some mineralocorticoid
cm - in?
2.5cm = in
EARLY very delayed bone age in young short child
Test?
GH def
can do insulin or arginine stimulation
bone age, chron age, height age in nutrition def?
height «_space;Bone age = chron age
best way to assess growth delay?
compare bone age to chronological age
bone age, chron age, height in hypothyroid?
bone age < height < chron age
macroglossia, jaundice, enlarged anterior fontanelle, pooro feeding, umbilical hernia in newborn?
congenital hypothyroid
when to test for congenital hypothyroidism in newborn?
w/in 24 hrs
test to ddx Graves from Hashimoto?
radioactive iodine uptake: high in Graves, low in Hashimotos
when to start lipid and eye screening in kids w/ DM1?
Age 12
expected lab finding in insulin resistance related to cholest?
low HDL
5 sx of metabolic syndrome?
- high TG
- low HDL
- HTN
- Hyperglycemia (Fasting > 100)
- truncal obesity
Fluid replacement in DKA?
20cc/kg boluses in first hour,
1/2 deficit replaced in first 16 hrs
amount of K that can be given if low potassium in DKA?
60meq K / Liter
when to add Glucose into fluids in DKA?
when it drops to < 300
if/when should bicarb be used in DKA?
Goal bicarb?
Only when pH is < 7.1 to bring to 7.2 max and not if hypokalemia present b/c this causes incr Co2 in CSF compared to blood (cerebral edema risk)
bicarb goal is 15
fluid replacement in hypernatremic dehydration and hyperosmolar diabetic coma?
slow and steady! replace fluids over 36-48 hours
define hypercalcemia?
Ca >11mg/dL
Causes of hypercalcemia?
WISH
- Williams
- Ingestion (thiazide, Vit A or D) / prolonged immobilization
- Skeletal disorders
- Hyperparathyroid
Drug that can be used to tx Hypercalcemia?
Lasix
Define hypocalcemia?
Ical < 4.5 mg/dL (1mmol/L)
Total cal: < 8.5 mg/dL
Causes of hypocalcemia?
PINK: Pseudohypoparathyroid Intake / Immune (Digeorge) Nephrotic syndrome: low alb/low cal Kidney: renal insuff, secondary hyperparathyroid
painful muscle spasms
seizures
vomiting
long QT
Hypocalcemia
developmental delay, short, obese, moon facies, calcified basal ganglia?
pseudohypoparathyroidism: high PTH and hypocalcemia
Two types of vitamin D resistant rickets and how to ddx?
Tx of each?
Genetics?
Type 1: LOW 1, 25 OH vit D (kidneys don’t produce it)
Treat with 1, 25!
Type 2: HIGH 1, 25 OH Vit D (there is end organ resist to it)
Treat with Ca infusions… very difficult
Both are AR
most common type of rickets in US? inher?
CAuse
Tx
X linked dominant hypophosphatemic rickets
eXcess phosphate loss, cannot convert 25 –> 1, 25 OH D
Tx w 1, 25 and phosphate
