Endocrinology Flashcards
Pathologic gynecomastia
pre-pubertal age
- rapid progression
- abnormal testes
- galactorrhea
- severe acne
- HTN
Gynecomastia investigations (specific tests)
LH, FSH, testosterone, estradiol, hCG, TSH, prolactin, testicular or adrenal ultrasound
Features of familial short stature
- height < 2SD for age/sex
- normal growth velocity
- predicted adult height appropriate for mid-parental height
- bone age = chronologic age
Constitutional delay
- slowing of growth velocity in first 3-5 yrs
- delayed entry into puberty
- often family history
- predicted adult height appropriate for mid-parental height,
- delayed bone age
Growth hormone deficiency
- clinical features
- lab/Ix features
- below average growth velocity
- delayed bone age (may be advanced relative to height age)
- low IGF-1, IGF BP3
- low response on 2 GH stim tests
(height falls off before weight)
RFs for GH deficiency
congenital: septo-optic dysplasia
acquired: craniopharyngioma, pituitary adenomas
Central precocious puberty investigation for males and females <= 5 yrs
MRI pituitary
Criteria for diabetes diagnosis
- Fasting BG > 7
- Random BG > 11.1
- 2hr OGT glucose > 11.1
ISF calculation
100/ Total daily dose
DKA criteria
- BG >11
- pH < 7.3 or bicarb < 15
- ketonemia (blood BHB>= 3 or mod-large urine ketones)
Female puberty
- boobs
- pubes
- grow
- flow (typically at breast stage 4)
Male puberty
- testes increase
- then phallus and scrotum
- then pubic hair
- height occurs when testes exceed 10-12 mL
Testicular size
prepuberty vs. puberty
prepuberty < 2.5cm (4mL)
Puberty > 2.5cm (4mL)
Delayed puberty age
absence of secondary sexual characteristics after:
- age 13 in girls and
- after age 14 in boys
Klinefelter syndrome
features of puberty
47 XXY
- puberty begins at appropriate age, penile enlargement and pubic hair (but does not progress)
- disproportionately small, firm testes, gynecomastia, infertility
(learning and behavioural difficulties)
Turner Syndrome
puberty and features
45 X to mosaicism (45 X, 46XX)
- mean adult height 144cm
- gonadal failure 96%
- infertility 99%
Precocious puberty
ages and red flags
Ages: before 8 in girls and before 9 in boys
Red flags: rapid progression, bone age advanced > 2 yrs, predicted adult height < 150 or 2SD below MPH, CNS S+Sx
Premature thelarche features
- isolated breast development
- 6-23 months
- does not exceed SMR III
NO CHANGE in growth velocity/growth percentile
Premature adrenarche features
- pubic hair +/- axillary hair, body odor, acne but NO thelarche
= early secreation of adrenal androgens, but NO change in growth percentile and bone age = height age
GnRH dependent vs. independent precocious puberty
Independent (aka peripheral):
- puberty differs from normal sequence,
- for girls, estrogen dependent effects usually predominate
- for boys: testes are inappropriately small in size or asymmetric
SIADH vs. DI vs. CSW
- volemia
- u/o
- serum Na
VOLEMIA: - SIADH = eu or hypervolemic - DI + CSW = hypovolemic U/O: - SIADH =decreased - DI + CSW = increased serum Na: - SIADH = decreased - CSW = decreased - DI = increased
SIADH vs. DI vs. CSW
- serum osmolality
- urine Na
- urine osmolality
SIADH = decreased serum osmolality, increased urine Na and urine osmolality DI = increased serum osmolality, decreased urine Na and urine osmolality
serum osmolality: - CSW: decreased
urine Na: CSW = increased ++, urine osmolality: CSW = increased
Micropenis
Clitoromegaly
Posterior labial fusion
- stretch penile length <2.5cm in term infant (1.9cm in Nelsons)
- clitoromegaly > 9mm
- Anogenital ratio > 0.5 cm (distance from anus to posterior fourchette divided by anus to base of phallus)
46 XX DSD
- CAH
- virilizing maternal disease
- maternal androgen use
- ovotesticular DSD, XX testicular DSD, gonadal dysgenesis
labs: 17-OHP, serum electrolytes, glucose, ACTH, renin, testosterone, LH, FSH
46 XY DSD
- leydig cell failure
- tesosterone biosyntehtic defect
- 5 alpha reductase deficiency
- androgen receptor disorder
- gonadal dysgenesis e.g. 45X/46XR)
- rare forms of CAH
Labs: testosterone, dihydrotestosterone (hcg stim), LH, FSH, mullerian inhibiting substance, electrolytes, glucose
Congenital hypothyroidism newborn screen
- TSH
will not pick up CENTRAL hypothyroidism
but majority is primary hypothyroidism aka thyroid dysgenesis (80%)
chronic lymphocytic thyroiditis (Hashimotos thyroiditis)
features
- diffuse enlargement of thyroid
- increased TSH
- positive antibodies (anti-thyroid peroxidase, anti-thyroglobulin)
Graves disease
features
- 95% have goiter
- thryotropin receptor stimulating antibody
- eye disease less common in chidlren than adoelscents
Treatment for hyperthyroidism
Methimazole
PTU causes liver failure
CAH features
- genetics and defects
- autosomal recessive
- most common = 21 hydroxylase (75% are classic salt wasting)
- elevated 17 OHP
Addison disease features
Nonspecific sx: weight loss, fatigue, hypotension, hyperpigmentation, hyponatremia, hyperkalemia, hypoglycemia
- elevated Renin and ACTH
- early am cortisol is low
- negative corticol stim test
Treatment of adrenal crisis
Minor stress = 2-3x replacement dose of HC = 40mg/m2/day
Major stress = 100mg/m2 IV/IM stat (25 < 3, 50 3-12, 100>12y)
Cushing syndrome vs. cushing disease
Syndrome: sx from excess glucocorticoids e.g. causes include: hypothalamic, pituitary, primary adrenal, ectopic ACTH, iatrogenic (if <5 think McCune Albright)
Disease = excess PITUITARY ACTH production e.g. pit adenoma
Normal responses to LOW CALCIUM
- PTH
- bones
- 1,25 OH D
- urine loss
- increased PTH
- increased bone resorption
- increased 1,25 OH D
- decreased urinary losses
Pediatric osteoporosis definition
- low bone mass as measured by DXA
- clinically significant fracture history
(fracture history e.g. 2+ long bones by 10 yrs, 3+ long bones by 19 yrs, 1+ vertebral fractures at any age)
Screening for T2DM indications
- 3+ RFs in nonpubertal chidlren beginning at 8 years of age OR 2+ RFs in pubertal children
- PCOS
- IFG and/or IGT
- Use of atypical antipsychotics
RFs for T2DM (as indications for screening) (4)
- obesity BMI >= 95th percentile
- high risk ethnic group e.g. African, Arab, Asian, Hispanic, Indigenous, South Asian
- 1st degree relative with T2DM and/or exposure to hyperglycemia in utero
- S+Sx of insulin resistance e.g. acanthosis nigricans, HTN, dyslipidema, NAFLD,
SMR in males pubic hair
1 = none 2 = scant, long 3 = darker, starting to curl 4 = resembles adult type but less quantity 5 = adult distribution, spread to thighs
SMR in females pubic hair
1 = none 2 = sparse, lightly pigmented 3 = darker, beginning to curl 4 = coarse, less than adult 5 = spread to medial surface of thigh
SMR in females breasts
- preadolescent
- breast mound
- breast and areola enlarged
- areola and papilla form secondary mound
- mature, areola part of general breast contour
SMR in males testes and penis
1 - preadolescent
2 - enlarged scrotum, minimal change in penis
3 - larger scrotum, penis lengthens
4 - larger scrotum and dark, penis glands and breadth increase
5 - adult size
Indications for GH (approved by FDA)
- GH deficiency
- Turner syndrome
- Noonan syndrome
- Chronic renal failure (before transplant)
- idiopathic short stature
- SGA short stature
- Prader Willi
- SHOX gene abnormality
First line evaluation for amenorrhea
- TSH, prolactin, FSH, HCG (and u/s if primary amenorrhea)
Features of congenital hypothyroidism
- wide open ant and post fontanels
- HC may be slightly increased
- prolonged physiologic jaundice
- feeding difficulties
- resp difficulties
- lethargic
- constipation
- large abdo with umbilical hernia
- hypothermia
- edema of genital
- CV: slow pulses, heart murmurs, cardiomegaly and pericardial effusions
- macrocytic anemia
Undiagnosed congenital hypothyroidism ( 9 features)
- developmental delays
- stunted growth, short extremities, HC N or increased,
- large open fontanels
- hypertelorism, depressed bridge of nose, narrow palpebral fissures, swollen, eyelids, thick, broad tongue
- delayed dentition
- myxedema
- carotenemia
- low hairline on forehead
- hypotonia
NBS will miss certain types of hypothyroidism:
- those with delayed TSH elevation
- central hypopituitary hypothyroidism
- may need repeat for same sex twins due to transfusion of euthyroid blood from unaffected to affected twin
Risk Factors for cerebral edema in DKA
- Age < 5 yrs
- new onset diabetes
- greater severity of acidosis
- high initial serum urea
- lower initial pCO2
- rapid admin of hypotonic fluids
- IV bolus of insulin
- early Iv insulin infusion
- failure of serum sodium to rise during treatment
- use of bicarbonate
Screening in T1DM
- nephropathy
yearly screening at 12 yrs of age in those with T1DM > 5 yrs
- screen with first morning or random urine ACR
Screening in T1DM
- retinopathy
- yearly screening at 15 yrs of age with duration of T1DM>5 yrs
- can be q2 yrs if good glycemic control etc.
screen with direct ophthalmoscoy or slit-lamp fundoscopy or fundus photography
Screening in T1DM
- neuropathy
- children >= 15 yrs with poor metabolic control after 5 yrs of T1DM
- examine for sx of numbness, pain etc. and vibration sense, light touch and ankle reflexes
Screening in T1DM
- dyslipidemia
- screen at 12 and 17 yrs
screen < 12 if BMI > 97th, fam history - screen with TC, HGL-C, TG, LDL-C
Diabetes targets
- A1C
- fasting preprandial gluc
- 2hr postprandial gluc
A1c <= 7.5%
pre meal gluc: 4-8
2hr post meal gluc: 5-10
Peak growth velocity
- females
- males
Females: breast stage II to III
Males: genital stages IV-V
Causes of hypocalcemia
- neonatal causes
- hypoparathyroidism
- vitamin D deficiency
- calcium deficiency
- disorders of phosphate, magnesium
Lab findings of hypoparathyroidism
- Ca is low
- PO4 is high
- ALP is normal or low
- 1,25 vitamin D = usually low
- Mg is normal
- PTH levels are low
- prolonged QT
- widespread slowing on EEG
Treatment of hypocalcemia
Emergency treatment of tetany: IV calcium gluconate
Other treatment:
- calcitriol (active vitamin D)
- adequate calcium intake
Hypercalcemia causes
- Neonatal
- hyperparathyroidism
- familial hypocalciuric hypercalcemia
- excessive calcium or vitamin D
- neoplasia
- immobilization
Treatment of hypercalcemia
Immediate therapy:
- saline hydration
- +/- loop dieuretic
- calcitonin
- bisphosphonates
- avoidance of Ca containing supplements
- steroids in some
- hemodialysis in severe
Hypervitaminosis D labs
- elevated Ca
- elevated 25-OHD
- elevated PO4
- PTH appropriately decreased
+/- renal insufficiency, anemia, normal 1,25-D
Micropenis
- definition
- investigations
- 2.5SD below mean in size
- stretched length <1.9cm (2.5cm as per Hamilton)
Ix: - karyotype, anterior pit function, testicular function, MRI brain
Central precocious puberty
- etiologies
- idiopathic
- organic brain lesions
- hypothalamic hamartoma
- brain tumors, hydrocephalus, head trauma, myelomeningocele
- hypothyroidism (prolonged and untreated)
Treatment of central precocious puberty
GnRH AGONISTS
e.g. leuprolide acetate (lupron)
Premature thelarche
- Features and
- Findings on eval
- Management
- isolated breast development in first 2 yrs of life
- may regress after 2 yr, often persist for 3-5 yr
Eval: - bone age is normal or slightly advanced
- baseline FSH and the FSH response to GnRH may be greater than normal controls,
- LH and estradiol are undetectable
- pelvic u/s and GnRH stim test are rarely indicated, Mgmt: need continued observation!
Premature adrenarche
- features
- appearance of sexual hair before age 8 in girls or 9 in males without evidence of maturation
- often slightly advanced in height and osseous maturation
- slowly progressive and no therapy required
Atypical premature adrenarche
Pts with precocious pubarche that have 1+ systemic androgen effect:
- marked growth acceleration, clitoral/phallic enlargement, cystic acne or advanced bone age
- requires ACTH stim test and 17OHP to rule out nonclassical CAH
PCOS triad
- oligo-ovulation or anovulation
- clincial or biochemical hyperandrogenisms
- ovaries with polycystic morphology on u/s
(generally need 2 of 3)
Vitamin D deficient rickets lab findings
- Ca
- PO4
- ALP
- 25-OH D
- urine Ca
- urine PO4
Calcium: normal or low PO4: low 25-OH D: low 1,25-OH D: anything ALP: high urine Ca: low Urine PO4: high
Manifestations of rickets
General: FTT, listless, weakness, fractures, protrubing abdomen Head: craniotabes, frontal bossing, delayed fontanel closure, delayed dentition and caries, craniosynostosis Trunk: rachitic rosary, scoliosis, kyphosis, lordsis Extremities: enlargement of wrists and ankels, valgus/varus deformities Hypocalcemic sx (tetany, seizures, laryngeal spasm)
