Endocrinology Flashcards
Obesity RF:
- maternal wt at start of pregnancy
- *pregnancy wt gain
- maternal DM
- *maternal smoking
- IUGR
- *LGA
- genetics= parental obesity (more about genetics than envirn’t alone)
- *Low SES (vs. developing nation more link with high SES)
Protective:
- BF
- higher maternal education
2 y.o. chid adopted. T or F: this patient will be obese regardless of bio parents?
False.
Will be thin if bio parents thin.
Define obesity
min. 97th %tile (WHO chart)
Name the mnemonic for causes of obesity:
The Obesity “GAMET”
- Genetic Syn
- Acquired
- Monogenic
- Endocrine
- Tumour (hypothal)
Provide one example of a dx that causes obesity in each GAMET category:
GAMET=
- Genetic= abN P/E
> Prader Willi Syn (neo low tone, small hand/feet, IQ, hypogonad)
> Bardet Biedl (polydactyly, hypogonad, retinal)
> Alstorem (DM + eye+ IQ)
- Monogenic (CC in < 6 mo. b/c no satiety)
> MC4R defect (Leptin deficiency) - Hypothalamic Tumour
> Hypopituitarism
- Endo (not gaining ht) > Cushing > GH deficiency > Hyperinsulinemism > Hypothyroidism
- Acquired (highly heritable)
List complications of obesity via system:
CNS: pseudotumour cerebri
CVS: dyslipidemia, HTN
Pul: OSA, asthma
Endo: T2DM, Metabolic syndrome, PCOS
GI: gallbladder dx, non alcohol fatty liver dx
Ortho: SCFE, tibia vara or Blount dx (bowing of tibia), MSK issue (joint or back pain)
Neuro: migraines
Behave: anxiety, depression, low SE
List obesity screening:
Start: 10 y.o. then q2y (or earlier if early puberty or signs of complications)
- AST, ALT
- Fasting Lipids (TG, HDL, LDL)
- HbA1C
Define normal ages for puberty in M and F:
M: 9-14
F: 8-13
What is the first sign of puberty in F?
Breast bud (thelarche)-> Adrenarche (pubic hair)-> Growth ++ -> Menarche (at Tanner 4)
what is the first sign of puberty in M?
Testicular enlargement (> 4cc or 2.5 cm) -> Penile growth -> Pubic Hair -> Growth +++ at tanner stage 4-5
How long is menarche after thelarche?
Usually 2 years
Where are girls and boys near their 12th birthday?
F: Just about to have menarche (12.5 years)
M: Adrenarche (Pubic Hair)
At Tanner Stage 4 where are F and M?
F= Double breast contour + Menstruation. M= Growth spurt.
Describe the F Tanner Stage for Breast Development:
1= preadolescent *2= breast mound, areola increased 3= breast + areola enlarge, no sep *4= Areola second mound 5= mature nipple projects
Describe the F Tanner Stage for Pubic Hair:
1= preadolescent *2= sparse, medial labia 3= darker, start curl *4= coarse, less < adult 5= adult
Which is true in puberty:
- Double breast contour Tanner 3
- menses Tanner 4
- Max penile growth Tanner 2
- Axillary hair Tanner 3
Menses Tanner 4.
- Double breast T4
- M enlarge penis at T3
- Voice change T4 (breaks in T3)
- Axillary hair T4
Describe the male Tanner Stages:
1= Testes < 4cc
No pubic hair
No penile growth
2= *Testes 4 cc
Pubic hair minimal
Penis early increase
3= Testes 12 cc
*Pubic hair coarse dark curly on pubis
* Penis increase ++
Voice may break
4= Pubic growth just not fully spread
*++ growth spurt
Axillary hair, voice, acne
5= adult
Facial hair
What is the action of insulin:
Glycogen synthesis
Action of glucagon:
Gluconeogenesis
What do the growth curves look like for:
- Familial Short Stature
- Constitutional delay
- Russel-Silver (Prenatal)
- CF or RF (Post natal)
Familial: start and stay just below
Constitutional: normal till 6-9 mo then fall off and catch up at end); normal velocity in the middle
Prenatal: start and stay parallel ++ below
Post-natal: FINE -> FALL
chronic dx= wt fall before ht
endo= wt fine, ht fall
Indications for GH therapy in short stature:
“Turn, Grow, Prader Willi SIR”
>Turner >Growth H deficiency >Prader Willi >SGA (not caught up by 2y.o.) >Idiopathic (2.25 SD corrected for bone age= man < 5'3" or F < 4'10") >RF (chronic; pre transplant)
Other from Nelson’s: SHOX gene abnormality, Noonan syndrome
Pro and Con of starting GH in Prader Willi
(+)= may prevent excess wt gain later
(-): can increase risk of sleep apnea
General GH risks:
- Pseudotumour cerebi
- SCFE if high BMI
T or F: Cushing’s is most common endocrinopathy causing short stature?
False
- Hypothyroidism most common.
Recommended screening test for Cushing disease?
AM cortisol.
Recommended screening test for GH deficiency?
IGF-1= screen
Confirm= GH stimulation test
Who needs to be assessed for short stature?
- Slow growth rate (< 5cm/year btwn 3-12 y.o.)
- Crossing % tile post 1.5 y.o.
- Well below genetic potential
- Ht < 3rd % tile
How do you calculate mid-parental height:
Dad + Mom’s ht (+/- 13)
= x
= x/2
= 10 cm above and below are 2SD
Genetic potential= this target range
T or F: 4 y.o. child growing 3 cm/year is normal.
False.
Btwn 3-12y.o. = 5 cm/yr
Then puberty= 12 cm/year
Describe your approach to short stature:
- Growing at normal rate.
- W/in Genetic Potential?
= YES to both= constitutional or familial
= NO to either= Pathologic
If pathologic short stature how do you separate it clinically?
Proportionate = wing span w/in 5% of ht + upper:lower segment 1:1
- Prenatal: born small, dysmorphic etc.
> Russell Silver, Turner, SHOX deficiency - Post-natal: chronic dx (wt off first) vs. endo (CNS, hormone = ht off)
> hypothyroidism, GH deficiency, CNS
Disproportionate= Scoliosis +/- Genetics referral (achondroplasia)
T or F: constitutional growth delay has normal growth velocity.
Mainly true.
- wt + ht decrease near end of infancy (< 2 y.o.)
- THEN NORMAL curve
- then accelerate near end of adolescence
T or F: girls usually stop growing ~2 years after starting their menses?
True
How much do girls grow after their onset of menses?
Royal College: 5cm-6 cm.
Describe two causes of GH deficiency:
Congenital: genetic gene mutation
Acquired: Radiotherapy from CNS tumour (i.e. pituitary adenoma, craniopharyngioma)
Acquired: Infection (Meningitis, encephalitis)
Definitive dx of GH deficiency established via?
Absent or low levels of GH in GH stimulation test.
Other: IGF-1 Low
Bone Age delayed.
When do you think of GH deficiency:
- Severe short stature (ht < 1st %tile or > 2.5 SD)
- <4-5 cm/year growth or cross two major % tile
- Features (hypoglycaemia, blue sclera, crytochordisim, microphallus, doll like fat, CNS tumour or radiation)
Triangle facies + thin skin with blue sclerae. Short stature. Dx?
Russell-Silver Syndrome
Which region on the Y chromosome causes M development?
SRY gene on Y chromosome
What is the default of gonad development?
F
- Need SRY from Y chromosome to make testis
If androgen insensitivity syndrome (Receptor issue) what does the BB look like?
Normal testes (because has SRY) but phenotypical F because T effects don’t happen
5-alpha reductase deficiency looks like?
look F at birth
(T not changed to DHT) but get secondary male traits at puberty
47 XXY=
Klinefelter
45 XO=
Turner
45X/46XY
Mixed gonadal dysgenesis
T or F: most CAH are 21-hydroxylase deficiency?
True
List investigations for ambiguous genitalia?
- Karyotype + FISH for SRY region on Y
- US (Mullerian structures)
- Adrenal: 17-hydroxyprogesterone + lytes + glucose
- If see gonad/testes= LH, FSH, T, DHT, hcg stimulation test (measure T before and after)
T or F: The most common cause of 46XX ambitious genitalia are virilizing CAH.
True
Disorder of decreased peripheral sensitivity to T causing ambiguous genitalia=
Androgen Insensitivity Syndrome
Most common form of male disorders of sexual differentiation?
Androgen Insensitivity Syndrome
AIS (androgen insensitivity syndrome) versus alpha-5-reductase deficiency?
AIS= Testes make T but does not affect target cells. No puberty.
5 alpha= Testes make T but not DHT. But Lots of T at puberty= male stuff happens! = masculinization at puberty
1 week old with ambiguous genitalia, V + lethargy. Dx=?
CAH
CAH baby B/W:
Waste salt= Low Na + High K!
- metabolic acidosis
- ACTH very high
- cortisol low
- glucose low
Confirmatory test= am cortisol + ACTH stimulation test
Adrenal cortex layers?
GFR
Salt-Sugar-Sex
Adrenal Cortex…
Glomerulosa= Aldosterone (Salt)
Fasciculata= Sugar (Cortisol)
Reticulata= Sex (androgens)
Adrenal Medulla… Adrenaline
Primary Adrenal Insufficiency: Name two congenital and two acquired causes of adrenal insufficiency:
Congenital
- 21 hydroxylase deficiency CAH
- Adrenal hypoplasia
- Adreno-leukodystrophy
Acquired
- AI = Addison’s Dx
- Infection: TB, HIV
- Infiltrative: CA, amyloidosis
Secondary Adrenal Insuff. Name cause?
= lack ACTH (central)
- drop cortisol but not aldosterone
- chronic steroid use
- Surgery (pit alter)
- Pituitary Tumour radiation
Low na, high K. Metabolic acidosis. Baby with ambiguous genitalia? What test?
Congenital Adrenal Hyperplasia
17-hydroxyprogesterone
How do you treat CAH?
Salt + Sugar + Steroid + Support
- Hydrocortisone
- Fludrocoritsone
- IVF/ ABC
- Call Endo
Perineoscrotal hypospadias, ++ phallus and no palpable testes. Dx?
Partial androgen insensitivity.
How do you remember Hashimoto versus Grave’s?
hashimOtO= O= hypO
- antibodies against thyroid peroxidase (TPO) and/or thyroglobulin
gRavE’s= ER = hypER
- antibodies against TSH receptor = rev up= thyroid stimulating immunoglobulins
T or F: anti-thyroid peroxidase (TPO) antibodies are present in most kids with lymphocytic thyroiditis?
True.
T or F: Primarily B cell infiltration for lymphocytic infiltration (Hashimoto)?
False.
- infiltration of lymphocytes (most T cells) + plasma cell leading to follicle atrophy
Best way to monitor effectiveness of thyroid replacement in Hashimoto?
TSH
Tx indicated if >10
What is used to determine initial dose of replacement in Hashimoto?
free T4
+/- TSH (sometimes subclinical still used)
What is the most common cause of thyroid dx in kids?
Lymphocytic Thyroiditis
= Hashimoto Thyroiditis
T or F: anti-thyroglobulin peroxidase (TPO) antibodies are present in most kids with lymphocytic thyroiditis?
False.
< 1/2
T or F: most people with lymphocytic thyroiditis are euthyroid ppt?
True.
+/- goitre
+/- growth retardation
Name two conditions lymphocytic thyroiditis is associated with:
- T21
- Turner
- T1DM
- Celiac Dx
If subclinical hypothyroid (high TSH and normal free T4) - do you tx?
Controversial
- most until growth and puberty done and then R/A to ensure no impact on bran as levels vary
All are seen in hypoparathyroidism except?
- increased ICP
- candidiasis
- carpopedal spasm
- hyporeflexia
Hyporeflexia!
Low PTH
= Low Ca
= Muscle cramp, pain, numb, stiff, spasm, sz
+ HYPER reflexia
+ mucocutaneous candida, h/a, ICP, cataracts etc.
List 5 clinical findings of congenital hypothyroidism:
- large AF
- coarse facies
- big tongue
- hoarse cry
- edema
- umbilical hernia
- hypotonic
- lethargic/ low activity
- poor feed
- prolonged jaundice
T or F: if TSH > 40 and T4 low ( if tested) you should start ASAP once confirmatory BW drawn (while awaiting results)
True
List two reasons for false (+) and (-) newborn thyroid screen:
False (+):
- screen before 24h old
- prematurity
False (-):
- Critical illness
- post-transfusion
List 2 reasons for congenital goitre.
- Congenital hypothyroid
2. anti-thyroid or iodides during pregnancy to tx maternal thyrotoxicosis
T or F: all babies born to F tx w/ antithyroid med in T3 need studies at birth.
True
- typically if need tx only few weeks once med out of system.
What is the leading cause of preventable intellectual disability in the world?
Iodine deficiency.
Most common cause for acquired goitre?
Lymphocytic Thyroiditis (hashimoto)
T or F: if you see an asymptotic goitre you just watch and re-image later?
False.
- prompt investigation for cause + thyroid f’n
- TSH, T4, anti-TPO antibodies
List two medication to use with Graves disease:
= Propranolol (symptomatic)
= Methimazole (1st line)
How does T2DM usually present?
- Teen
- Obese
- N/V + Abdo Pain
- Polyuria
- 10%= DKA (typically black)
List longstanding 1DM complication:
Heart (HTN, lipid) -> Kidneys -> Neuro -> Eyes
HTN (2x/year screen)
@ 12 y.o. + min. 5 yr dx
- Dyslipidemia (or < 12 if high BMI, fhx of hyper lipid or early CAD)
- Nephrology (random alb: Cr)
- Neuro Hx + P/E
@15 y.o. + min. 5 yr dx
= yearly retinopathy
How do you halt progression of microalbuminuria in a DM?
ACE inhibitor (i.e. enalapril)
How do you manage patients NPO for OR with diabetes?
Night before= full dose basal long acting insulin (glargine= Lantus or determir= Levemir)
Morning of= 50% intermediate dose (NPH or Lente)
In OR= Dextrose fluids + IV fluids
What condition causes acanthosis nigricans?
Insulin resistance.
Commonly associated with type 2 Diabetes.
How do you diagnose T1 DM?
HbA1C 6.5%
OR fasting plasma BG > 7
OR 2 hour oral glucose tolerance test > 11.1
OR plasma glucose > 11 w/ classic symp
How do you diagnose DKA?
DM= glucose > 11
Urine Ketone (+)
pH < 7.3
bicarb < 18
BEST method to screen for diabetic nephropathy?
First morning urine for albumin to Cr ratio.
When do you start ophthalmology screen for diabetic retinopathy in T1DM?
IF 15 y.o. + > 5yr from diagnosis
= start annual screen.