Endocrinology Flashcards
As acidosis is corrected, what do you have to worry about in DKA rx?
Loss of K+ in urine, so should monitor carefully with EKG if necessary
When can cerebral edema most commonly happen after treatment initiation?
4 to 12 hours
What does hypokalemia look like on EKG?
U wave and Q-U prolongation
What is the Somogyi phenomenon?
hypoglycemia leading to rebound hyperglycemia.
So check 2am - if low then it is this
What is the rx to somogyi phenomenon?
decrease nighttime long-acting insulin
What is the Dawn phenomenon in DM?
Early AM glucose - check 2am, if still high, than increase nighttime long-acting insulin
What do you check on sick days for DM?
Check BG frequently, use rapid acting insulins,
Describe 2 dose insulin regiment?
2 shots/day with short&long acting insulin
2/3 daily in AM, 1/2 in PM
2/3 long-acting, 1/3 short-acting
How many hours of TV/computer use/day?
2 hrs
Obese at age 6, likelihood of obese as adults
25%
Obese at 12, likelihood of obese as adults
75%
Most common complication of obesity.
Low self-esteem
What is the glucose level and serum bicarbonate, effective serum osmolarity in hyperglycemic hyperosmolar syndrome?
Glucose >600mg/dL
Serum bicarbonate >15mmol/L, 320 mOsm/L
Rx for hyperglycemic hyperosmolar syndrome
aggressive hydration with 0.45% saline, insulin later
Tall and fat, endocrine or not
Obesity
Pattern: mildly obese, short, hypoglycemia, micropenis, bone age delay, single maxillary incisor, optic nerve hypoplasia, cleft lip/palate
Growth hormone deficiency - hypopituitarism
Pattern: floppy baby, mildly retarded, sucking problems, very obese as he grows, hypoplastic penis/scrotum, small testicles and hands/feet, large appetite
Prader-willi syndrome
Pattern: moderate obesity, round face with short neck, delayed dental eruption, aplasia, short 4th, short 4th metacarpals/metatarsals, extraskeletal calcification, variable hypocalcemia, hyperphosphatemia
PseudohypoPTH
Albright hereditary osteodystrophy
Pattern: obesity, mental deficiency, retinal dystrophy, polydactyly, syndactyly, brachydactyly, broad, short feet, abnormal kidneys, small penis/tests (hypogonadism)
Bardet-Biedl syndrome
A ciliopathic disorder
Pattern: obesity later, hypotonia, brushfield spots, clinodactyly with simian crease, endocardial cushion defect, small penis and small testicles
Down syndrome
Dopamine prolactin relationship
DA causes reduction or prolactin
DI also causes what?
Hypernatremia
If hypo or hypernatremia, what labs do you want to do?
urine osmolality, serum osmolality, serum and urinary sodium
High urine osmolality, low serum osmolality
SIADH
Low urine osmolality, high serum osmolality
DI
Treatment for SIADH
Fluid restrict, 1000cc/m2/day or less
What is level of TSH for congenital hypoTH dx?
TSH >25
Pattern: prolonged jaundice, severe growth and DD, constipation, coarse features, umbilical hernia and large anterior fontanelle
congenital hypoTH
What are endocrine problem should you be aware of in DM patients?
10-30% also have Hashimoto, autoimmune polyglandular syndrome II
Pattern: growth fall-off, mild relative weight gain, dry skin/myxedema, delayed relaxation phase of DTRs, coarse hair, mild hair loss
HypoTH
Range of TSH in hypoTH
> 50, 100, 200
Pattern: high TSH, microcytic anemia
HypoTH
What dose of levothyroxine for newborn with hypoTH?
10-15 mcg/kg/day
What dose of levothyroxine for older pts with hypoTH?
100mcg/m2/day
If longstanding or TSH>100, what regiment of levothyroxine do you want to give - aka uptitration plan
Start at 1/4 to 1/3 dose and work up slowly over 3-4 weeks
What are three major causes of hyperTH?
- Graves autoimmune
- Thyroiditis with release of LT4 from gland in acute phase of Hashimoto or DeQuervain (painful, negative Ab’s)
- Inappropriate use of LTH for weight loss
Pattern: jittery, weight loss, agitation, fatigue (cannot sleep), heat intolerance-diaphoresis, proptosis/exophthalmos
Graves hyperTH
Pattern:
+TSH receptor Ab, + Anti TP, +Anti TG
Graves hyperTH - don’t be fooled by other antibodies
What is high risk side effects of methimazole?
agranulocytosis
Rx of Graves
- Radiactive idoine ablation
- Thyroid surgical resection
- Can use idoine (to slow down met of TH), prednisone, propanolol
Any solitary nodule needs what kind of workup?
Thyroid US
Uptake scan
Fine needle aspiration
Percentage of solitary nodule that is malignant
20%
Rapid growth, firm nodule, +FH of medullary CA, history of neck radiation
Thyroid cancer
Characteristic of thyroid nodule that is less likely to be cancer.
Cystic nodule, TPO/TG Ab’s
What initiates genital structure development?
Y chromosome with SRY causing gonads to develop towards testicles
What does maternal HCG signal in the fetus for genital structure differentiation?
Testes to secrete T, DHT –> external genital vrilization
What stabilizes the Wolffian internal structures?
Testosterone
Testes also produce AMH to do what?
induce female structures (Mullerian) to regress
At what week is genital structure formed?
14 weeks, shape, but not size
What hormone/level/problem seen with 46XY DSD
Subnormal T or DHT
Insensitive to T
What hormone/level/problem see with 46 XX DSD
excess maternal androgens, exogenous androgens, fetal adrenal CAH
Ovotestes 46 XX, 46 XY or mosiac
both ovary and testicle
Pattern: External female genitalia, internal no uterus, testicles present, no pubic/axillary hair, breast tissue at puberty, no menses
Complete androgen insensitivity - X-linked
Pattern: ambiguous genitalia, internal male, no uterus, some pubic hair
Partial androgen insenstivity
Sign of low DHT?
genitalia not virilized
At puberty for pt with 5 alpha reductase deficiency, why can you see virilization?
Testosterone is excessively high and can virilize
Pattern:
Female salt-wasting, ambiguous genitalia,
21-OH deficiency
Pattern:
Male salt-wasting, early adrenarche/puberty
21-OH deficiency
Pattern:
Teenage girl, hirsutism, menstrual irregularities
21-OH deficiency non-classical
Pattern:
Virilized female, hypertension
11-B hydroxylase deficiency
what are complications of untreated 11-B hydroxylase deficiency
advanced bone age and early adrenarche
Workup of CAH
pre +/- post ACTH stim is gold standard 17 OH progesterone (21 OH deficiency) DOC (11 beta OH deficiency) 17 OH pregnenolone (3-B hydroxysteroid) Renin/aldosterone DHEA, andro, and ACTH
What is the RX for acute salt wasting-adrenal crisis?
Fluids + hydrocortisone 25mg IM/IV then 100mg/m2/d divided q6 hours
What is chronic rx for salt wasting and virilizing?
hydrocortisone 15-25 mg/m2/day, fludocort (mineralcortidoid)
Follow up 17OHP, andro, renin levels q3 months
What are causes of Addison’s disease (primary adrenal insufficiency)?
- Autoimmune destruction APS1 (AIRE) adrenal and mucocutaneous candidiasis APS2 (Schmidt) adrenal, DM I, Hashimoto
- Infection (TB)
- Adrenal hemorrhage post-infection (WFS)
- Adrenal hypoplasia congenita
- Adrenoleukodystrophy
Pattern: Salt-losing crisis in neonatal period, 21 OH is not deficient, no virilzation in females, normal male genital development
Adrenal hypoplasia congenita
What is genetic cause of adrenal hypoplasia congenita
NROB1 (DAX-1)
How do you treat adrenal hypoplasia congenita?
Same treatment as in 21 OH, but lower doses of HC are needed than in CAH
Pattern:
Normal neuro development, then loss of milestones, clumsiness, adrenal insufficiency, grumpy and irritable
Adrenoleukodystrophy
ABCD1 gene x-linked
Pattern:
Hypotension, hyponatremia, hyperkalemia, acidosis, weight loss, vomiting, hyperpigamenation
Acute severe adrenal insufficiency
Causes of Cushing symptom
- Exogenous steroids
- Cushing’s disease (ACTH production)
- Adrenal tumor
- Ectopic expression
Pattern: growth failure, truncal obesity, acne/hirsutism, hypertension, purple striae, weakened bones
Cushing syndrome
How to test for Cushing’s syndrome
Overnight dexamethasone suppression, 1mg at 11pm, check cortisol level at 8am, if no suppression, dx made
24-hour urine for free cortisol
Pattern:
Headache, HTN, palpitations, sweating
Pheochromocytoma - caused by excess catecholamines
Dx of pheochromocytoma
Urinary catecholamines, urinary metanephrines, MRI of adrenals, MIBG scan
Glucose level to dx hypoG
Pattern: new born, low glucose, big tongue, umbilical hernia
Beckwith Wiedemann syndrome
Pattern: newborn, low glucose, just got UA catheter
malposition of UA catheter too high up supplying excess glucose to pancreas so reactive response
4 hormones that raise blood glucose - how many has to be deficient to cause hypoglycemia
epinephrine, glucagon, cortisol, growth hormone
Pattern: Large for gestation age baby, with seizures, hypoG, pre and post prandial, needs lots of glucose
Hyperinsulinism
Workup in baby with hypoglycemia
paired insulin/glucose, UA for ketones
Pattern: hypoG at random times, no ketones
Hyperinsulinsim or FA oxidation
Pattern: hypoG and midline defects or nystagmus
Pituitary (GH/Cortisol)
Pattern: hypoG after overnight fast,
GH/cort or FA oxidation defect
PTH’s net effect
increase Ca, decrease P
Vit D’s net effect
increase absorption of Ca and P
Vit D’s effect on PTH
Feed back inhibition on PTH
PTH increases Ca by 3 mechanisms
- increase bone resorption
- increase Ca resorption from kidney
- increase Vit D (25 to 1,25 dihyd) to increase gut absorption
Calcitonin net effect
decreases Ca blocks osteoclastic resorption.
it is secreted by C-cells
Hypocalcemia s/sx
Tetany, seizures, chvostek (tap on cheek, 7th nerve), trousseau (bp cuff), irritability
Hyper/Hypo Ca workup
1) iPTH w/ paired calcium
2) 25, hydroxy & 1,25 dihydroxy
3) Mg (co-factor for PTH secretion) & P
4) Urinary Ca and Creatinine
Where is the problem in hypoPTH, pseudoPTH
1) Secretion/production
2) bad receptor
Labs seen in hypoPTH
low Ca, high PO4, low PTH
4 disorders that can causes hypoPTH newborns/infants
1) DiGeorge/velocardiofacial
2) CHARGE assocation
3) Autoimmune polyglandular syndrome I/II
4) Familial hypoPTH (AD)
Pattern: cardiac/palatal defects, broad nose, long fingers, T-cell dysfunction (infection), deletion of 22q11 region
DiGeorge/Velocardiofacial
Pattern:
low Ca, high PO4, high PTH (>300)
pseudoPTH
What disorder is associated with pseudoPTH
Albright hereditary osteodystrophy
Pattern: Short stature, shortened 4th/5th digit, DD, subcutaneous calcification
Alright hereditary osteodystrophy
Pattern: low Ca, low P, high Alk Phos
Vit D deficiency
Major causes of Vit D deficiency
Decreased intake, absorption (ADEK, CF pt), production (excessive use of sunscreen, dark skinned children at risk)
How much VitD needed in first 2 months?
400 IU/day
How much to replete VitD deficiency?
1000 IU/day
What is calcitriol
activated in Vitamin D - 1,25-dihydroxycholecalciferol or 1,25-dihydroxyvitamin D3
Pattern: normal Ca, low P and high urine P, high Alk Phos, bowing of legs, widening cupping and fraying of distal metaphyses
Hypophosphatemic rickets
Cause of hypophosphatemic rickets
Genetic - X-linked (not sure what the mutation is)
Rx of hypophosphatemic rickets
Calcitriol and P
Pattern: polyuria, nephrolithiasis, bone pain, depression, ulcer/nausea
hypercalcemia
Pattern/cause:
Low iPTH, hi Ca, low Phos,
Check PTHrP, most likely high. Secreted by tumor.
Pattern/cause:
Low PTH, hi Ca, hi Phos
Hypervitaminosis D
Pattern:
Normal PTH, hi Ca
Benign familial hypercalcemia fro CASR gene mutation, receptor is insensitive to Ca
What genetic disorder should you think of when you see hypercalcemia?
Williams Syndrome
Pattern/cause:
High PTH, elevated Ca, low phos
HyperPTH-parathyroid adenoma
Rx for hypercalcemia
- Hydration
- furosemide (short term), 3. Glucocorticoids ( short term - incr urinary output), 4. Calcitonin (short term - tachyphylaxis - loses efficacy)
- Bisphosphonates (holds calcium/phosphorus in bones, more long term)
Babies double weight by when and triple by when?
2x by 4 months
3x by a year
Growth velocity during 1st, 2nd, and 3rd year.
1st year - 24cm/yr
2nd year - 12cm/yr
3rd year - 8cm/yr
(year x GV=24)
What is growth velocity in boys and girls at puberty peak?
Puberty peak 10cm/yr (boy)
8cm/hr (girl)
Pattern:
Short, delayed bone age, normal labs, following own curve
Constitutional delay of growth AKA late bloomers
Pattern:
Short, normal labs, family is short
Familial short or tall stature
Formula for determining potential height of child
If boy - average parents, add 5 inches (13cm from to moms)
If girl - average parents (subtract 5 inches from dad) +/- 4 inches
What should you think of if pt is short
Growth hormone deficiency
What genetic mutations associated with growth hormone deficiencies?
HESX, PROPR1, POUF1, GHR (Laron)
Pattern:
Recurrent low blood sugar in infancy, growth slows after 6 months, growth velocity falls from curve
Growth hormone deficiency
How do you diagnose GH deficiencies?
IGF-1, IGF-BP3, bone age of hand/wrist (not specific), GH stimulation tests?, Pituitary MRI
Side effects of GH
pseudotumor cerebri, scoliosis, SCFE, thyroid and cortisol deficiences
6 common syndromic short stature
- Trisomy 21
- Turner Syndrome
- Noonan syndrome
- Prader-Willi syndrome
- Pseudo-hypoPTH (Albrights hereditary osteodystrophy)
- Russell-Silver syndrome
Pattern:
Short stature, low hairline, wide spaced nipples, poor breast development, elbow deformity, shortened metacarpal, webbed neck
Turner
Pattern:
Short stature, low hairline, shield chest, right sided cardiac (pulmonary stenosis), no renal defects, usually fertile, boy or girl
Noonan syndrome
Difference between Turner and Noonan
Cardiac problem: Turner - Coart/bicusp AV; Noonan - pulmonary stenosis Renal Turner - yes; Noonan - no Fertility Turner - infertile; Noonan - fertile
3 common symptoms b/w Turner vs Noonan
Short stature, low hairline, shield chest
Pattern:
Short stature, DD, obesity/hyperphagia, hypogonadotropic, hypogonadism (small phallus/testicles, pubertal delay)
Prader-Willi syndrome
Pattern:
Small at birth, limb assymetry, triangular head, cryptoorchidism, no catch-up growth
Russell-Silver
7 common causes of tall stature
- Klinefelter syndrome (47XXY)
- marfan syndrome
- Homocystinuria
- HyperTH (end height not different, just accelerated growth)
- GH excess (gigantism)
- Precocious puberty (only temporary)
- Soto syndrome (cerebral gigantism)
Pattern: short stature, triangular facies, low hairline, high arched palate, hypoplastic nipples and increased carrying angle
Turner - missing X
What heart and renal conditions is associated with Turner syndrome?
Coarctation of aorta
Horseshoe kidney
What test do you do when you are suspicious for Turner?
Karyotyping, LH/FSH (they should be high because of ovarian failure)
What thyroid problem is associated with Turner syndrome?
Antibody positive chronic lymphocytic thyroiditis and hypoTH
What is the initial screen for hypoTH?
TSH, then free thyroxine and antithyroid antibodies (thyroperoxidase, antimicrosomal or anithyroglobulin)
Presence of Y chromosome in Turners results in what?
Androgenization, gonadal malignancy often requiring ppx gonadectomy
What is the height and weight growth like for Cushing syndrome?
Weight is normal to high, attenuation of height growth
What are the two thyroxine binding protein? Which is seen in excess in 1 to 8000 individuals? What blood measurement does this problem make inaccurate?
TBG - can be seen in excess
TBPA
TT4 is useless
T3 is made in what two ways?
15% by thyroid gland, rest from deiodination from T4
What conditions affect deiodination of T3?
Fed state is proportional to
Can hypoTH affect bone?
Yes, it can delay bone age
What is the most common cause of acquired primary hypoTH?
Chronic lymphocytic thyroiditis (Hashimoto’s)
What antibodies must be measured to evaluate for lymphocytic thyroiditis?
Again thyroperoxidase enzyme and thyroglobulin
If you are still suspicious a child has hypoTH but negative for antithyroid antibodies, what additional testing should you do?
TH US and then technetium or radioactive iodine imaging
Describe in DETAIL 6 features of hyperTH
- Weight loss and increased appetite
- Decreased strength, muscle weakness, loss of thenar and hypothenar eminence muscle mass, decreased sports performance.
- Moist skin, thinning hair, skin darkening
- Poor sleep, nervousness, anxiety, irritability, pruritus, nocturia, hyperactivity, tremors
- Decreased school performance
- Decreased menses in girls
In addition to high free T4, what other blood value is high in hyperTH?
T3 and TSH IgG in Graves
How can you test whether hyperTH is due to subacute thyroiditis or Graves disease?
Radioactive iodine
Subacute thyroiditis - low uptake
Graves disease - high uptake
What is the major life-threatening complication of rx for DKA?
Cerebral edema
Outline the major steps to Rx of DKA?
- Hydrate but sparingly
- Correcting K and insulin
- Correcting acidosis
How should fluid replacement be done in DKA?
Calculated steady replacement of 0.45% or 0.9% with glucose and K as needed
How should K replacement be done in DKA?
As soon as child starts urinating, then start K repletion
What caution should be taken when correcting peripheral acidosis?
Bicarbonate dissociates in bicarbonate ion and CO2 so can increase intracellular and CNS acidosis to increase risk of cerebral edema
What happens with sodium in DKA?
High losses in urine
What thyroid problem is seen in 10% of type 1 diabetics?
Chronic lymphocytic thyroiditis - Hashimoto thyroiditis (autoantibodies - like the ones that cause the diabetes)
What can pt with Hashimoto thyroiditis eventually develop?
Interestingly HypoTH or Graves disease - ? burns out or acquire additional antibodies
What gene is associated with polylglandular autoimmune syndrome type 1?
AIRE
What autoimmune disorder is a part of polyglandular autoimmune syndromes?
Type 1 diabetes, candidiasis, hypoPTH, Addison, pernicious anemia, vitiligo
What autoimmune problems are associated with polyglandular autoimmune syndrome type 2?
Autoimmune thyroid disease, diabetes, adrenal insufficiency
What is the most likely outcome in baby with congenital hypoTH who does not receive treatment within the first few days of life?
Cognitive deficits
What are the signs of growth hormone excess?
Widened spaces between teeth, large hands and feet, increased soft-tissue thickening
What disorder is upper to lower segment ratio useful in clinical diagnosis?
Marfan syndrome
What test should be ordered to work up male precocious puberty?
Serum T, 17-hydroxyprosterone, dehydroepiandosterone, LH/FSH and HCG (which mimics LH to activate Leydig cells to produce T)
What tumors makes HCG?
Germ cell in CNS, mediastinum, liver (hepatoblastomas)
Adrenoleukodystrophy is caused by what gene mutation and what builds up as a result?
ABCD1, defective oxidation of LCFA in peroxisomes. VLCFA accumulate in myelin, adrenal glands and elsewhere
What is the typical pattern on growth chart for familial short stature?
In first 2 years, reach certain growth percentile and follow the curve
What age is bone age radiograph useful for predicting adult height?
6 or 7 years
What signs can be associated with early menarche?
Thelarche a couple of years before
What are signs of gonadal puberty in girl?
Menarche and thelarche (breast bud)
What are signs of adrenal puberty (adrenarche or pubarche)?
Adult body odor, pubic hair, acne
What is Addison’s disease?
Primary adrenal insufficiency
What happens to sodium and potassium in Addison disease?
Low serum sodium (cannot hold it without mineralcorticoid), high K (cannot excrete K)
What happens to cortisol and ACTH levels in Addison?
Low cortisol, high ACTH
Addison is a deficiency in what?
Aldosterone
What are complications of aldosterone deficiency?
Dehydration, break down of muscle tissue, hyponatremia, hyperkalemia, elevated BUN and acidosis
What are manifestation of ACTH deficiency?
Cortisol deficiency –> weight loss, nausea, inability to maintain blood pressure, low IV volume leads to release of vasopressin
Why isn’t there hyperkalemia in ACTH deficiency?
Aldosterone is still released
Hyperpigmentation accompanies which adrenal axis problem?
Primary adrenal insufficiency (high ACTH)
Pattern: firm, enlarged thyroid
Hashimoto, antibody against thyroperoxidase and thyroglobulin
What is random glucose level that indicates DM?
> = 200mg/dL
HgbA1c level for DM dx
> =6.5%
Fasting plasma glucose level for DM dx
> = 126mg/dL
what are marker antibodies for DM Type 1
Anti-islet, anti-insulin, Anti-GAD65, Anti-ZnT8A
How much B-cell mass must be destroyed before symptoms of diabetes occur?
80-90%
What is the honeymoon period in DM type 1?
With insulin, remaining live cells light up and start producing insulin, because they too need insulin to function - but then they are attacked
Insulin’s 4 roles
- Increases glucose uptake, along with amino acids and lipids
- Decreased glucagon production and glycogenolysis
- Enhances glycogen, protein and fat synthesis
- Inhibits fat breakdown (lipolysis) and ketogenesis
What four hormones increase glucose?
- Growth hormone
- Glucagon
- Epinephrine
- Cortisol
What causes the lactic acidosis in DKA?
Hypertonic dehydration
What pH and HCO3 classifies as mild, moderate, severe DKA?
Mild
How to get true sodium level in setting of hyperglycemia?
Corrected Na+ = measured Na + 0.016 (measured glucose - 100)
For what three reasons do you give insulin in treatment of DKA?
- Turns off ketogenesis
- Minimizes osmotic diuresis
- Enhances tissue substrate utilization
Does bicarbonate and phosphate affect recovery rate in DKA?
No
What is harm of excessive chloride in DKA Rx?
Prolong acidosis
When Na+ is low in obtunded DKA pt, what do you need to think of?
Cerebral edema secondary to SIADH
Pattern: HA, decrease in LOC, decreased HR, increased BP 4 to 12 hours after rx initation
Cerebral edema
Pattern:
Small at birth, limb assymetry, triangular head, cryptorchidism, no catch up growh
Russell-silver - Will use GH for them although not deficient
Adrenarche
Aka pubarche - development of pubic hair and acne secondary to adrenal androgens
Thelarche
Development of breast tissue
Gonadarche
Enlargement of testicles or ovaries
LH acts on what
gonad to produce T and ovarian androgens
FSH acts on what
Gonads to produce estrogens and inhibin
Tanner 2 female
Areola - labial hair
Tanner 3 female
Mound and smooth contour - hair creeps to mound
Tanner 4 female
Nipple starts protruding - fuller hair
Tanner 5 female
Full contour - triangular
Progression of female development
Thelarche - 8 to 13 Adrenarch/pubarch 9-14 Growth spurt Menarche - 2 yrs after start of puberty average 12.4 yr T-A-G-me
Tanner 2 male
testicle enlarge, dropping of testicle
Testicle enlargement occurs to what volume
to 4cc
Progression of male development
Testicular enlargement 9-14 Pubic hair follows 6mo-1yr later Penile enlargement Growth spurt Tanner III-IV Axillary hair - then facial hair T-H-P-G-A
Age of puberty that qualifies as precocious
8 for girls
9 for boys
Precocious puberty workup
LH, FSH, estradiol/testosterone, bone age (often advanced 2-3 years)
How do you interpret leuprolide (GNRh) stimulation test
Rise in LH –> PP
No rise - benighn premature thelarche
Suppression - peripheral puberty
Pattern:
Early development, low LH&FSH, high T or E2
Peripheral precocious puberty
What is cause of peripheral precocious puberty in boys only?
Constitutively active LH receptor in familial male gonadotropin-independent precocious puberty
Pattern:
Cafe au lait, fibrous dysplasia, prec pub
McCune Albright Syndrome - G protein abnormalitiy
Rx of central precocious puberty
Lueprolide, histrellin, GnRH agonists constant will agent, decreased LH/FSH
Rx of peripheral puberty
Remove offending agent, block peripheral effects of sex hormones (androgen receptor blockers; estrogen receptor blockers)
Delay puberty workup
LH,, FSH, estradiol, testosterone, TSH, chemistry panel, ESR, bone age
Age when puberty is considered delayed
13 in girls, 14 in boys
Pattern:
Normal height pre-adolescence, no growth spurt, may have adrenarche, anosmia
Kallman syndrome
hypogonadotropic hypogonadism
Two disorders associated with panhypopit
septo-optic dysplasia, empty sella syndrome
2 genetic syndromes associated with delayed puberty
Prader Willi syndrome
Leptin deficiency
Hypergonadotropic hypogonadism 5 causes
- Mumps orchitis
- Turner syndrome
- Klinefelter
- Functional ovarian failure
- Trauma, chemo, gonadal removal
Pattern:
Tall stature, eunuchoid proportions, gynecomastia, stalled puberty, testicles noted to be small during puberty
Klinefelter - start developing and then stall
What is the most common cause of childhood hypoglycemia?
ketotic hypoglycemia
What is the cause of ketotic hypoglycemia?
Imbalance between glucose utilization and production through hepatic, renal glycogenolysis and gluconeogenesis
Pattern: fasting hypoglycemia in child less than 8yo
Ketotic hypoglycemia
To determine if hyperinsulinism is the cause of low blood glucose, what should you measure and when and what results to anticipate?
At time of hypoglycemia, measure insulin and c-peptide. C-peptide is secreted with insulin so if low when insulin is high, more likely to be excess amt of exogenous insulin.
What is best first test for suspected ketotic hypoglyemia?
urine dipstick for ketones
Pattern: seizures, hypotonia growth delay, signs of rickets (prominent forehead, rachitic rosary, enlarged wrists and ankles).
Rickets: vit D deficiency
Pattern: slowed mentation, stupor, constipation, polyuria, renal calculi, extreme thirst
Hypercalcemia
Pattern: neuromuscular irritability like hypocal, nausea, loss of appetite
hypomagnesemia
Pattern: muscle weakness and changes in mental status, no neuromuscular irritability
Hypophosphatemia
What are some causes of hypercalcemia?
hyperparathyroidism, hypervitaminosis A (stimulates osteoclast activity), hypervitaminosis D, immoblization (osteoclast activation and relative bone resorption)
Rx for familial hypophosphatemic rickets?
Oral neutral phosphate salts with calcium (b/c phosphate takes Ca+ into bone)
Pattern: 2 year old with unilateral breast tissue
Premature thelarche caused by release of FSH and LH stimulating ovarian estrogen production and will regress by 2 years of age
Pattern: 3yo with lump that moves with swallowing and centrally located
Thyroglossal cyst –> surgical consult
What is the kinetics of ultrashort-acting insulins
Action begins about 10 to 15 minute after administration, peaks at 1 hr and lasts no longer than 3 to 4 hours
What are rules for sick days for type 1 diabetic kid?
- Check blood glucose every 2 hours
- check urine or blood ketones every 2 to 4 hours
- Provide small amounts of normal short-acting insulin every 2 to 3 hours as long as his blood glucose is >100mg/gL and he can consume sugar-containing liquids to stay hydrated
Causes of polyuria
DM, renal disease, DI, hyperTH, hyperCal, hypomag
Pattern: 11yo boy, nocturnal enuresis, no glycosuria, serum glucose normal, no UTI
hypercalcemia