Endo Flashcards
Girl with primary amenorrhea with No breasts (or just breast buds), No/scant hair, Elevated gonadotropins
Turner Syndrome (XO)
- short stature (could present as a younger child with isolated short stature, bone age=actual age, normal labs)
- webbed neck (cystic hygroma), pedal edema, wide spaced nipples, short 4th/5th metacarpals
- aortic coarctation, horseshoe kidney
- uterus present but streak ovaries
- Dx: HypERgonadotropic ovarian failure (high FSH). Negative progesterone challenge test (will not bleed 2 weeks later)
- Tx: Can treat with GH but NOT testosterone.
Girl with primary amenorrhea with breasts but No hair
Androgen insensitivity (aka testicular feminization) which is genetically XY. X-linked recessive.
- Blind-ending vagina. No uterus or ovaries. Testes are present in inguinal canal.
- Might see FH of “sterile maternal aunts” (actually males)
- Receptors are insensitive to androgens but Mullerian inhibitor hormone still works, resulting in regression of internal female structures without development of external male structures and later no adrenarche/pubarche (no hair, no menses). Estrogen still works so patients develop breasts.
Boy with gynecomastia, small testicles, tall stature, long arms/legs, mild intellectual disability
Klinefelter (47, XXY)
- 1-2:1000 Nondisjunction during egg/sperm meiosis
- Low testosterone, high LH and FSH
- Tx: Testosterone
- High risk of autoimmune d/o, diabetes, tumors, osteopenia
- “shy” “awkward” “below average in school”
- “low upper to lower segment ratio”
Teen girl with pubic hair but no breasts
Could be Low estrogen or androgen excess
Young girl with pubic hair but no breasts
Premature adrenarche (if bone age is normal, can likely observe)
Young boy with pubic hair, penile enlargement, +/- accelerated growth, with Small testes
Congenital adrenal hyperplasia, Exogenous steroids, or Virilizing tumor (the excess hormones are not coming from a central or gonadal cause). Technically this is not precocious puberty since testes are small.
Young boy with enlarged testes, pubic hair, penile enlargement, +/- accelerated growth
Precocious puberty. Elevated LH or bHCG and/or elevated gonadal androgens. Look for tumors
Young girl with breasts + vaginal bleeding or accelerated growth
Precocious puberty. If LH/FSH are elevated = central cause, usually idiopathic but sometimes pituitary tumor. Tx with Lupron (GnRH analogue will suppress LH/FSH).
If LH/FSH are not elevated but estrogen/progesterone are elevated = gonadal/TUMOR cause
Young boy with pubic hair without testicular enlargement
Premature adrenarche - very concerning for Congenital Adrenal Hyperplasia! Check 17-OH progesterone levels. (Adrenal tumor is less likely)
Young girl (usually a baby) with breast buds
Premature thelarche. Usually benign. Follow for other signs of precocious puberty.
Young girl with breast buds, being followed closely, develops early menses
Premature thelarche->Precocious puberty. Look for source of estrogen excess: exogenous, estrogen-secreting tumor, or central. Get endo consult.
When to get Bone Age Films
- Premature adrenarche
- Delayed puberty
13yo girl with no breast buds
Delayed puberty (no breast buds by 13yo). More concerning in girls. If bone age is w/in 1-2 y, can observe. If BA=CA, check FSH, LH, prolactin, and gonadal hormones. If FSH/LH are increased -> Turner syndrome. If FSH/LH are low -> consider eating disorder, exercise induced amenorrhea, or Kallman.
Amenorrheic 16yo who reached SMR4 breasts and hair at 13yo
Delayed puberty (no menses 2 yrs after SMR4 hair/breasts). More concerning in girls! Do primary amenorrhea work-up
Boy with SMR2-3 testicular and penile size with gynecomastia
Normal variant (50% of boys in SMR2/3 stages) Can be unilateral
Boy with small penis, delayed puberty, and anosmia
Kallman syndrome. Associated with other midline defects (SOD).
Child with decelerated growth, proportionate wt and ht, and delayed puberty. Delayed bone age mirrors height.
Constitutional growth delay (and delayed puberty). Benign and child will eventually reach full adult height.
Can consider tx with testosterone (but not GH).
(Young) Child with decelerated growth (crossing lines) and micropenis/small clitoris.
Growth hormone deficiency. Will see lack of GH release after administering insulin or arginine. Can have seizures due to hypoglycemia.
Child with decelerated growth of height with relative sparing of weight and markedly delayed bone age
Congenital growth hormone deficiency. Beware this answer choice - it is a common distractor.
Child with sharply decelerated growth and delayed bone age
Acquired growth hormone deficiency. Get brain MRI to look for pituitary tumor. Check other pituitary hormones
Anterior pituitary hormones
FLATPiG = FSH, LS, ACTH, TSH, Prolactin, and GH
Posterior pituitary hormones
Oxytocin and ADH/Vasopressin
Child with short stature, overweight, delayed bone age, dry skin, and constipation
Hypothyroidism
Child with accelerated growth and early adrenarche/puberty and premature closure of growth plates
Late onset congenital adrenal hypErplasia. Hyperandrogenism
Will ultimately have short stature
Child with low weight percentile with relative sparing of height
Could be nutritional disorder. Eventually might see decreased weight AND height. If drop in weight was rapid, consider GI/renal/metabolic pathology
Obese tall child with striae and advanced bone age
High caloric intake (Cushing’s patients are NOT tall)
Obese short child with delayed bone age
Hormonal/endocrine issue. (If no BA is provided, consider Cushing’s)
Child with falling weight and height curves but sparing of head circumference
Usually an endocrine issue. Sometimes constitutional growth delay or genetic short stature
Primary amenorrhea work-up: What and when (p.60)
What:
-Pregnancy test.
-Then, do Progesterone Challenge. 1) If patient has menses w/in 2 weeks, then there is enough estrogen but not progesterone (so no ovulation). Check LH level (high=PCOS; low->check prolactin and TSH. 2) If no menses, there is not enough estrogen. Check FSH level (high=ovarian failure or Turner’s; low=Central problem such as mass or hypothyroid).
-If androgenization, get testosterone and DHEA.
When:
no menses 2 yrs after puberty ended; 14-15yo with no breast development; 16-17yo even with breast development
Child with no menses for 6 months after periods had become regular or no menses for 12 mos if periods were irregular
Secondary amenorrhea.
Differential includes Asherman’s syndrome, Cystic fibrosis, Sarcoidosis, Tuberculosis, brain tumor, phenothiazines, nutrition
Child with no menses x 3 months, bradycardia, orthostasis, and hypothermia
Anorexia (bulimia causes irregular menses)
Child with irregular menses, obesity, hirsuitism, acne, and signs of insulin resistance
PCOS = a Clinical diagnosis. LH:FSH>2
PCOS can be secondary to other disorders, such as Cushing’s.
14yo boy with galactorrhea
Consider marijuana use
Normal (or slightly low) calcium
Low phosphorus
Option 1: Familial hypophosphatemic rickets, aka Vit D Resistant Rickets.
X-linked Dominant disorder (but still boys>girls)
Other labs: High Alk Phos, normal 25-Vit D, Normal-increased PTH, high urine Phos
Kidney cannot reabsorb Phos or convert 25-Vit D to 1,25-Vit D
Tx: Oral phos and 1,25-Vit D
Option 2: Initial vitamin D depletion (low 25-Vit D). Compensatory increased PTH temporarily normalizes calcium
Low calcium
Low phosphorus
Severe Vit D deficiency
PTH will be high
Low calcium
Normal phosphorus
Initial Vit D repletion of healing Vit D deficiency rickets
Low calcium
High phosphorus
Remember: PTH is supposed to promote ? Causes of this pattern include: Hypoparathyroidism Pseudohyperparathryroidism (PTH resistance) Phosphorus overload
Normal calcium
High phosphorus
Renal disease
Growth hormone excess
High phosphorus diet
Hypercalcemia - definition and symptoms
Calcium > 12
Sx: Shortened ST and QT segments, polyuria, plus “Bones (fx) , stones, moans (abd pain), and psychiatric overtones (fatigue, AMS, psychosis, coma)
Hypocalcemia - definition, symptoms
Calcium < 8.5 or iCal < 4.5
Correct total Ca by adding 0.8 to Ca for every 1 g/dL drop in albumin (from normal of 4)
Sx: Paresthesias, Tetany (carpopedal spasm aka Trousseau’s sign; Chvostek’s sign -> cheek spasm), Refractory seizures, Laryngospasm and tachypnea, prolonged QT-> death
Hypercalcemia - causes (7+)
Familial hypocalciuric hypercalcemia (benign, NTD), Williams syndrome, Vit D or Vit A ingestion, Thiazide diuretics, Skeletal issues (ex. casting. Tx with IV fluids and loop diuretics), Hyperparathyroid, Malignancy
Hypocalcemia - causes (early and late)
Early (first 3 DOL): HIE, IDM, IUGR, maternal hyperPTH (makes the baby hypoPTH)
Late (after DOL7): Vit D defic, hypoPTH, pseudohyperPTH, hyperphos, hypomag, hyperventilation, alkalosis, nephrotic syndrome, renal failure, rhabdomyolysis (low Ca-> high Ca), ethylene glycol, DiGeorge/22q11 deletion syndrome
Adrenal enzymes (p.77 in book)
1) 21-hydroxylase - cannot make aldosterone or cortisol. Salt-wasting CAH, low Na, high K. No HTN. High 17-OH Prog.
2) 18-hydroxylase - cannot make aldosterone
3) 17-hydroxylase - cannot make cortisol or androgens (CAH, low K. HTN. Metab acidosis)
4) 11-hydroxylase - cannot make cortisol (non-salt wasting CAH, pt will have normal Na levels but will have HTN)
- Causes of CAH in order: 21»11>17
Micropenis
Normal appearance but <2 cm
Testes present in scrotum
Diff dx: GH defic, Prader-Willi, Kallman syndrome (also has anosmia), and Panhypopit
Baby with normal testes/penis and rudimentary uterus and fallopian tubes
Mullerian inhibitor hormone deficiency (or receptor defect)
- Androgens work so see external male genitalia
- But MIH does not work so do not see regression of internal female genitalia
- Child is XY
Baby with ambiguous or female genitalia and XY karyotype
MALE pseudohermphradoism, aka incomplete masculinization.
- Due to inadequate androgen production during fetal dev affecting external structures
(has no female internal structures?)
Child with testicular and ovarian tissue
True hermphrodism
- Very rare, likely a decoy answer choice!
High ACTH, high cortisol
vs
Normal/low ACTH, high cortisol
Cushing’s disease (central cause)
vs
Cushing’s syndrome (exog or adrenal cause)
Pearl: if patient is tall, obese, with striae - it is not Cushing’s, it is high caloric intake.
High ACTH, low cortisol
High yield
Primary Adrenal insufficiency/deficiency aka Primary Addison’s disease (Adrenal gland issue)
Other sx: hypoglycemia (low cortisol), low Na and high K (low aldosterone), nonspecific sx, hyperpigmentation, appropriately high ADH
Causes: adrenal dysgenesis (X-linked congenital adrenal hypOplasia), impaired steroidogenesis (Smith-Lemli-Optiz; congenital adrenal hypErplasia/CAH), adrenal destruction (ex. autoimmune, adrenoleukodystrophy, adrenal hemorrhage, infection/TB, idiopathic)
Dx: ACTH stim test will NOT increase cortisol
Tx: hydrocortisone (glucocorticosteroid) AND fludrocortisone (mineralocorticoid)
Low ACTH, low cortisol
Secondary Adrenal insufficiency/deficiency, aka Secondary Addison’s disease (Pituitary problem)
Other sx: No issues with Na or K (aldosterone, renin-Angiotensin are fine). Can see midline defects
Dx: ACTH stim test WILL increase cortisol
Tx: Just hydrocortisone (not fludrocortisone)
N/V, malaise, hyperkalemia, hyponatremia, shock
Adrenal crisis
Tx: Saline, glucose, IV hydrocortisone
Baby with normal TSH but high T4 on newborn screen
Thyroxine-binding globulin deficiency (so total T4 looks low, but free T4 will be normal. TBG level will be low)
X-linked disease
No treatment is needed!!!
Baby with elevated TSH (and low free T4)
Hypothyroidism or Congenital hypothyroidism
Sx: Hoarse cry, puffiness, large tongue, large anterior and posterior fontanelles, hypotonia, abd distension, umbilical hernia, constipation, acrocyanosis/mottling.
Tx: Start levothyroxine right away to avoid irreversible cognitive damage. Repeat labs.
Child with thyroid nodule - what tests to get and how to interpret them?
Thyroid function studies: Low TSH suggests overactive thyroid tissue aka “hot” nodule, likely benign.
Ultrasound next choice. Then radioactive imaging as third choice. Cold nodule = inactive tissue = BAD
Child with thyroid nodule - what tests to get and how to interpret them?
Thyroid function studies: Low TSH suggests overactive thyroid tissue aka “hot” nodule, likely benign.
Ultrasound next choice. Then radioactive imaging as third choice. Cold nodule = inactive tissue = BAD, likely malignant tumor.
Fine needle aspirate is method of choice to dx suspicious lesions.
Baby with tachycardia, tremors, SVT in immediate newborn period
Neonatal thyrotoxicosis (neonatal Graves disease)
- Mom’s thyroid-stimulating-receptor antibodies cross placenta and cause problems in baby
- Can lead to heart failure in baby. Also IUGR and microcephaly.
- Tx: can give pregnant mom PTU. Levothyroxine helps too
Child with hyperactivity, trouble sleeping, disorganized thinking, emotional lability, weight loss, tachycardia, heat intolerance, ophthalmopathy, lid lag.
GravE’s DisEasE = hyperthyroid
Radioactive iodine uptake is HIGH
Might have goiter full of thyroid hormone
TSH very low to absent
Tx: Methimazole, iodine ablation, beta blocker. Less often use PTU due to high toxicity.
Child with painless, firm goiter/thyromegaly
Must do further testing to see if hypo or hyperthyroid.
If hypOthyroid = HashimOtO thyrOiditis, aka chronic lymphocytic thyroiditis.
Radioactive iodine uptake is LOW
High TSH, low T4 (can have transient thyrotoxicosis or normalization of T4 if TSH is high enough)
+TPO or +thyroglobulin antibodies
Thyroglobulin vs thyroxine-binding globulin
Thyroglobulin is found only in the thyroid gland
Thyroxine-binding globulin = TBG and carries thyroxine (T4) in the blood
Total T4 includes free T4 and T4 bound to TBG
Tx of DKA or HONK (hyperosmolar non-ketotic hyperglycemic state)
Replace fluid over 36-48 hours (to avoid cerebral edema)
Replete K with up to 60 mEq/L
Do not give hypertonic saline (low Na is likely pseudohyponatremia)
Add glucose to IV fluids once blood glucose < 300
Do not give bicarb unless pH < 7.1
Metabolic syndrome diagnostic criteria
Three of the following: -Abdominal obesity (waist circ > 90th%) -HDL < 40 -Triglycerides > 150 -Fasting glucose > 100 -Blood pressure > 90th% (Note: Acanthosis nigricans is NOT a diagnostic criteria)
SIADH lab values
Serum Na < 135
Serum osm < 275
Urine Na > 40 (Na excretion is not affected)
Increased urine spec gravity
Also, increased thirst and decreased frequency of urination
Baby with phallic-appearing or enlarged clitorus structure (ambiguous genitalia), no testes, has a uterus
Girl (XX) with congenital adrenal hypErplasia (CAH)
- Causes androgen excess which masculinizes the external genitalia but does not affect the internal structures and does not result in creation of testes
- Can have common urethral-vaginal orifice
- Administer hydrocortisone STAT to avoid adrenal crisis. and also to help prevent further virilization (will shut down ACTH which was driving excess androgens), draw 17-OH progesterone level, and then give hydrocort, fludrocort, saline, glucose
Baby with hyperpigmented scrotum
Boy (XY) with congenital adrenal hypErplasia (CAH)
- Excess ACTH causes hyperpigmentation. Excess androgens promote normal male external genitalia
- Newborn screen will show increased 17-OH progesterone, which might be the ONLY abnormality (i.e. baby boy might look totally normal at first)
- Administer hydrocortisone STAT to avoid adrenal crisis, draw 17-OH progesterone level, and then give hydrocort, fludrocort, saline, glucose
Diabetes mellitus type 2 diagnostic criteria
- HgbA1C > 6.5
- Fasting glucose > 126
- 2 h glucose > 200 (after 75 gm glucose load)
- Random glucose > 200 with symptoms of hyperglycemia
BASIC WORKUP OF DELAYED PUBERTY
Bone age helps determine whether the delay is constitutional.
Other imaging if there is a suspicion gonads are abnormal or absent.
FSH, LH, and either estrogen or testosterone (according to sex) to distinguish primary
and secondary problems.
TSH, T4, and prolactin
Karyotype in patients with primary hypogonadism.
Parathyroid hormone
Works to maintain ionized calcium levels by:
1) Releasing calcium from bones
2) Increasing calcium reabsorption by kidneys
3) Decreasing phosphate reabsorption by kidneys
4) Promote conversion of 25-Vit D to 1,25-Vit D by the kidneys
5) 1,25-Vit D then promotes absorption of calcium from the intestinges
