Endo

Question 1

Girl with primary amenorrhea with No breasts (or just breast buds), No/scant hair, Elevated gonadotropins

Answer 1

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.

Question 2

Girl with primary amenorrhea with breasts but No hair

Answer 2

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.

Question 3

Boy with gynecomastia, small testicles, tall stature, long arms/legs, mild intellectual disability

Answer 3

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”

Question 4

Teen girl with pubic hair but no breasts

Answer 4

Could be Low estrogen or androgen excess

Question 5

Young girl with pubic hair but no breasts

Answer 5

Premature adrenarche (if bone age is normal, can likely observe)

Question 6

Young boy with pubic hair, penile enlargement, +/- accelerated growth, with Small testes

Answer 6

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.

Question 7

Young boy with enlarged testes, pubic hair, penile enlargement, +/- accelerated growth

Answer 7

Precocious puberty. Elevated LH or bHCG and/or elevated gonadal androgens. Look for tumors

Question 8

Young girl with breasts + vaginal bleeding or accelerated growth

Answer 8

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

Question 9

Young boy with pubic hair without testicular enlargement

Answer 9

Premature adrenarche - very concerning for Congenital Adrenal Hyperplasia! Check 17-OH progesterone levels. (Adrenal tumor is less likely)

Question 10

Young girl (usually a baby) with breast buds

Answer 10

Premature thelarche. Usually benign. Follow for other signs of precocious puberty.

Question 11

Young girl with breast buds, being followed closely, develops early menses

Answer 11

Premature thelarche->Precocious puberty. Look for source of estrogen excess: exogenous, estrogen-secreting tumor, or central. Get endo consult.

Question 12

When to get Bone Age Films

Answer 12

• Premature adrenarche

- Delayed puberty

Question 13

13yo girl with no breast buds

Answer 13

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.

Question 14

Amenorrheic 16yo who reached SMR4 breasts and hair at 13yo

Answer 14

Delayed puberty (no menses 2 yrs after SMR4 hair/breasts). More concerning in girls! Do primary amenorrhea work-up

Question 15

Boy with SMR2-3 testicular and penile size with gynecomastia

Answer 15

Normal variant (50% of boys in SMR2/3 stages)
Can be unilateral

Question 16

Boy with small penis, delayed puberty, and anosmia

Answer 16

Kallman syndrome. Associated with other midline defects (SOD).

Question 17

Child with decelerated growth, proportionate wt and ht, and delayed puberty. Delayed bone age mirrors height.

Answer 17

Constitutional growth delay (and delayed puberty). Benign and child will eventually reach full adult height.
Can consider tx with testosterone (but not GH).

Question 18

(Young) Child with decelerated growth (crossing lines) and micropenis/small clitoris.

Answer 18

Growth hormone deficiency. Will see lack of GH release after administering insulin or arginine. Can have seizures due to hypoglycemia.

Question 19

Child with decelerated growth of height with relative sparing of weight and markedly delayed bone age

Answer 19

Congenital growth hormone deficiency. Beware this answer choice - it is a common distractor.

Question 20

Child with sharply decelerated growth and delayed bone age

Answer 20

Acquired growth hormone deficiency. Get brain MRI to look for pituitary tumor. Check other pituitary hormones

Question 21

Anterior pituitary hormones

Answer 21

FLATPiG = FSH, LS, ACTH, TSH, Prolactin, and GH

Question 22

Posterior pituitary hormones

Answer 22

Oxytocin and ADH/Vasopressin

Question 23

Child with short stature, overweight, delayed bone age, dry skin, and constipation

Answer 23

Hypothyroidism

Question 24

Child with accelerated growth and early adrenarche/puberty and premature closure of growth plates

Answer 24

Late onset congenital adrenal hypErplasia. Hyperandrogenism

Will ultimately have short stature

Question 25

Child with low weight percentile with relative sparing of height

Answer 25

Could be nutritional disorder. Eventually might see decreased weight AND height. If drop in weight was rapid, consider GI/renal/metabolic pathology

Question 26

Obese tall child with striae and advanced bone age

Answer 26

High caloric intake (Cushing's patients are NOT tall)

Question 27

Obese short child with delayed bone age

Answer 27

Hormonal/endocrine issue. (If no BA is provided, consider Cushing's)

Question 28

Child with falling weight and height curves but sparing of head circumference

Answer 28

Usually an endocrine issue. Sometimes constitutional growth delay or genetic short stature

Question 29

Primary amenorrhea work-up: What and when (p.60)

Answer 29

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

Question 30

Child with no menses for 6 months after periods had become regular or no menses for 12 mos if periods were irregular

Answer 30

Secondary amenorrhea. Differential includes Asherman's syndrome, Cystic fibrosis, Sarcoidosis, Tuberculosis, brain tumor, phenothiazines, nutrition

Question 31

Child with no menses x 3 months, bradycardia, orthostasis, and hypothermia

Answer 31

Anorexia (bulimia causes irregular menses)

Question 32

Child with irregular menses, obesity, hirsuitism, acne, and signs of insulin resistance

Answer 32

PCOS = a Clinical diagnosis. LH:FSH>2 | PCOS can be secondary to other disorders, such as Cushing's.

Question 33

14yo boy with galactorrhea

Answer 33

Consider marijuana use

Question 34

Normal (or slightly low) calcium | Low phosphorus

Answer 34

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

Question 35

Low calcium | Low phosphorus

Answer 35

Severe Vit D deficiency | PTH will be high

Question 36

Low calcium | Normal phosphorus

Answer 36

Initial Vit D repletion of healing Vit D deficiency rickets

Question 37

Low calcium | High phosphorus

Answer 37

``` Remember: PTH is supposed to promote ? Causes of this pattern include: Hypoparathyroidism Pseudohyperparathryroidism (PTH resistance) Phosphorus overload ```

Question 38

Normal calcium | High phosphorus

Answer 38

Renal disease Growth hormone excess High phosphorus diet

Question 39

Hypercalcemia - definition and symptoms

Answer 39

Calcium > 12 Sx: Shortened ST and QT segments, polyuria, plus "Bones (fx) , stones, moans (abd pain), and psychiatric overtones (fatigue, AMS, psychosis, coma)

Question 40

Hypocalcemia - definition, symptoms

Answer 40

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

Question 41

Hypercalcemia - causes (7+)

Answer 41

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

Question 42

Hypocalcemia - causes (early and late)

Answer 42

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

Question 43

Adrenal enzymes (p.77 in book)

Answer 43

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

Question 44

Micropenis

Answer 44

Normal appearance but <2 cm Testes present in scrotum Diff dx: GH defic, Prader-Willi, Kallman syndrome (also has anosmia), and Panhypopit

Question 45

Baby with normal testes/penis and rudimentary uterus and fallopian tubes

Answer 45

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

Question 46

Baby with ambiguous or female genitalia and XY karyotype

Answer 46

MALE pseudohermphradoism, aka incomplete masculinization. - Due to inadequate androgen production during fetal dev affecting external structures (has no female internal structures?)

Question 47

Child with testicular and ovarian tissue

Answer 47

True hermphrodism | - Very rare, likely a decoy answer choice!

Question 48

High ACTH, high cortisol vs Normal/low ACTH, high cortisol

Answer 48

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.

Question 49

High ACTH, low cortisol | High yield

Answer 49

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)

Question 50

Low ACTH, low cortisol

Answer 50

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)

Question 51

N/V, malaise, hyperkalemia, hyponatremia, shock

Answer 51

Adrenal crisis | Tx: Saline, glucose, IV hydrocortisone

Question 52

Baby with normal TSH but high T4 on newborn screen

Answer 52

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!!!

Question 53

Baby with elevated TSH (and low free T4)

Answer 53

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.

Question 54

Child with thyroid nodule - what tests to get and how to interpret them?

Answer 54

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

Question 55

Child with thyroid nodule - what tests to get and how to interpret them?

Answer 55

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.

Question 56

Baby with tachycardia, tremors, SVT in immediate newborn period

Answer 56

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

Question 57

Child with hyperactivity, trouble sleeping, disorganized thinking, emotional lability, weight loss, tachycardia, heat intolerance, ophthalmopathy, lid lag.

Answer 57

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.

Question 58

Child with painless, firm goiter/thyromegaly

Answer 58

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

Question 59

Thyroglobulin vs thyroxine-binding globulin

Answer 59

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

Question 60

Tx of DKA or HONK (hyperosmolar non-ketotic hyperglycemic state)

Answer 60

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

Question 61

Metabolic syndrome diagnostic criteria

Answer 61

``` 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) ```

Question 62

SIADH lab values

Answer 62

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

Question 63

Baby with phallic-appearing or enlarged clitorus structure (ambiguous genitalia), no testes, has a uterus

Answer 63

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

Question 64

Baby with hyperpigmented scrotum

Answer 64

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

Question 65

Diabetes mellitus type 2 diagnostic criteria

Answer 65

- HgbA1C > 6.5 - Fasting glucose > 126 - 2 h glucose > 200 (after 75 gm glucose load) - Random glucose > 200 with symptoms of hyperglycemia

Question 66

BASIC WORKUP OF DELAYED PUBERTY

Answer 66

 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.

Question 67

Parathyroid hormone

Answer 67

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