Endocrinology and Adolescence Flashcards
Most common genetic skeletal dysplasia
Achondroplasia (disproportionate dwarfism)
If ht age matches bone age in someone small for age….
Constitutional delay
Type II polyglandular Autoimmune syndrome
Big association between thyroiditis and addison’s disease. Often occurs with type I diabetes. Celiac disease, primary hypogonadism and myasthenia gravis also occurs.
Occurs in adults usually.
Reducing substances in the urine (cupric sulfate) detect generally what…
galactose and glucose
Type I Polyglandular Autoimmune syndrome
Occurs in children with mucocutaneous candidiasis, hypoPTHism, and primary adrenal insufficiency. Type I diabetes does not occur.
HLA Inheritance
Genes very close together on chromosome 6, threfore inherited as a discrete group/haplotype from each parent. There is a 1/4 chance of inheriting the same HLA as another sibling.
Klinefelter’s Syndrome
47 XXY. Main presentation: infertility and gynecomastia. Primary hypogonadism (small testes, oligospermia, azospermia). Can also get osteoporosis, erectile dysfunciton, low libido. Normal ht, wt and head circ. Treat with testosterone around puberty to improve situation.
Achondroplasia
Most common short limb disproportionate dwarfism. Sitting height normal. Abnormal endochondral ossification. Present at birth. Autosomal dominant.
Growth hormone can increase height.
Types of dwarfism
Short limb (Achondroplasia, hypochondroplasia, and metaphyseal chondrodysplasias) vs short trunk
Link between adrenal system/adrenarch and HPG axis
None.
Way to distinguish adrenal from HPG actions in puberty:
tanner stage.
Juvenile athlete triad
disordered eating or excess exercise, decreased bone mass, amenorrhea.
things that affect puberty timing
Nutrition/nutrional states: diabetes (insulin), stress, obesity, anorrhexia, starvation. chronic illness.
Effects of testosterone on development
thicker cortical bone, growth of pubic hair. Increases muscle mass. Acne. In girls: hirsutism, anovulation, amenorrhea, clitoromegaly.
Effects of estrogen on development
Low levels needed for grwoth spurt and bone mass acrual. high levels close the epiphysis.
In women, responsible for secondary sexual characeristics, fat distribution pattern, lower vaginal pH, increased vaginal length, LH surge trigger.
Pubic hair and breasts/testes…
must tanner stage individually.
Typical times of puberty
Onset: girls 7-13; boys 9-14 Typical start: 10–11; boys at ages 11–12 Major landmark girls: menarche at 12-13 Major landmark boys: spermarche 13 Completion: girls 15-17, boys 16-17
Hormone most responsible for growth and closure of epiphysis
Estrogen.
Kallman Syndrome and Idiopathic Hypogonadotropic hypogonadism
Rare genetic conditions. Associated with anosmia or hypoosmia (kallman: affects males and females). No other abnormalities. IHH has normal smell.
Caused by deficient GnRH secretion. Can do GnRH replacement.
Present with absent or incomplete puberty as well as: erectile dysfunction/dyspareunia, low libido, low muscle mass,
Precocious Puberty Standards
Boys: 1) Gynecomastia prior to gonarche or pubarche in boys. 2) Pubic hair or gonardche before 9.5
Girls: Pubic hair or thelarche before age 7-8. Menstruation before age 10.
Or… girls age 8, boys age 9
Premature thelarche
Occurs before the age of 3 in girls. Can be benign so long as there is no other development of sexual characteristics. This can regress. Girls will likely still menstruate at a normal age.
Puberty order for boys
testes enlarge (4cc/2.5cm), pubic hair (6-8 mo later), penis/scrotum enlarge/scrotum reddens, axillary hair, spermarche (T3), facial hair (T4+), adult height.
Tanner for boys
T2: scrotum enlarges
T3: penis, scrotum enlarge, spermarche
T4: scrotum darkens, inc penis width
T5: adult size
Late puberty/cause for concern
No menarche after age 15/16 or 5 years after thelarche.
>5 years for boys from T2 to T5
Puberty order: Girls
breast buds, pubic hair, growth spurt, axillary hair, breasts mature, menarche, adult ht.
Tanner for girls
T2: buds, T4: secondary mounds,
Causes of hypothyroid
Central (tumors, sheehan, drugs) vs peripheral.
Autoimmune (hashimoto), Post partum, De Quervain/Subacute Thyroiditis, drug inducced, iatrogenic, iodine deficiency.
Hashimoto’s Thyroiditis
Most common hypothyroid after age 6 years. Onset usually insidious/slowly progressive.
sx/Ssx: wt gain, fatigue, depression, constipation, dry skin, memory loss, hair loss, menorrhagia, bradycardia, edema, diastolic hypertension, decreased DTR’s
Diagnostics of Hashimoto’s thyroiditis
High TSH, low T4, low T3 but high rT3. Eosinophilia. Anti-TPO and anti-thyroglobulin Ig’s.
Complications of hypothyroidism
Depression, wt gain, hyperlipidemia, hyperprolactinemia, anemia.
Causes of Pseudo-Precocious Puberty
Gonadotropin independent.
Exogenous sex steroid, steroid secreting tumors (ovary, testes, adrenal), CAH, McCune Albright, Russel silver Sydnrome
G6PD presentation
Xlinked. Heinz bodies. Presents variably but often at 3-4 months age. Failure to thrive, anemia, jaundice, hypoglycemia, acidosis. Jaundice, splenomegaly during crisis. Hx of gallstones.
True precocious puberty is most often caused by…
lesion to CNS
Addressing parental concerns about height in a child…
Assess Tanner Stage, Mid parental ht. growth history of parents.
See growth charts. Measure limb proportions. Assess for Turners, Noonan and Russel Siver. Assess nutrition and health status.
Labs: CBC, TSH, E7, IGF1,
Bone age
Laron Syndrome
Growth hormone resistance causing dwarfism
Cortisol variations diurnally
Lowest around midnight, highest at 8:00AM (ish)
PseudohypoPTHism
CAused by resistance to PTH. High serum PTH but to low Ca, high serum Phosphate. Can be hereditary (Albright Herediatry Osteodystrophy).
Congenital Adrenal Hyperplasia
Group of auto recessive disorders due to lack of cortisol and/or aldosterone. Presentation varies with degree of lack of enzyme activity. Can present with advanced bone age, precocious puberty or salt wasting crisis. Often obese.
80% is due to 21-Hydroxylase deficiency.
Two most common forms of CAH and their characteristics
21-hydroxylase def and 11Beta hydroxylase deficiency
21-hydroxylase deficency
low cortisol, high androgens, low aldosterone. Can cause salt wasting crisis and failure to thrive if severe. (low Na, high K, shock). 1-hydroxyprogesterone increased or metabolite in urine.
11-Beta hydroxylase deficiency
low cortisol, excess androgens, increased mineralocorticoid activity. females do not go through puberty but look phenotypically female.
Dx: increased 11-deoxycortisol
Cause of hypertension in CAH
deoxycorticosterone, which has mild mineralocorticoid effects.
Wilson’s Disease
Autosomal recessive. Low Cu and low ceruloplasmin but causes deposition of copper in tissue. Presents first with liver dysfunction (elevated enzymes ie. ) and then with neurological and behavioral problems in adolescence. Keiser Fleisher rings.
Rickets
High PTH leads to low serum phosphate, high urinary phosphate but normal Ca. Bowing limbs, ricketic rosary.
Causes of rickets
congenital. Acquired: meds (anticonvulsants like phenobarbitol and dilantin), vit D deficiency, disease, vegans/vegetarianism.
Vitamin D homeostasis
Vitamin D3(cholecalciferol) is made in skin. First hydroxylated at 25 position in liver (calcidiol, serum is good indicator of Vit D status). Then at 1 position in kidney (needs PTH). Action: increase P and Ca from intestine and bone, increase Ca reabsorption from kidney and P excretion.
Some signs of vit D deficiency in kids
bow legs/knock knees, kyphoscoliosis, generalized hypotonia, craniotabes, delayed closure of AF, metaphyseal flaring/cupping.
hyperpigmentation can be a sign of…
icnreased ACTH: CAH, cushings… etc.
47-XYY
Normal male phenotype with normal puberty, testosterone level, fertility and IQ. No difference.
47 XXX
Mostly normal but increased incidence of psych distrubrance and premature ovarian failure.
Bone differences: adults vs kids
Kids bendier bones thus are more likely to have incomplete fractures (green stick and buckle fractures). Kids dont get tendon/ligament injuries.
Hypogonadism, mental retardation, polydactyly, retinitis pigmentosa and loss of night vision, obesity.
Laurence Moon Beidal Syndrome. Auto recessive.
Blue sclera
osteogenesis imperfecta. bone matrix deposition defect. Normal Ca and P.
Hormone elevated in MCT
calcitonin.
Addisson’s Disease
Deficient cortisol and mineralocorticoids (chronic adrenal insufficiency). Can be caused by meningococcocemia (Waterhosue Friederichson syndrome).
Sx: fatigue, weakness, hypotension, hyperpigmentation (ACTH), myalgia, headache, nausea, vomiting.
Hyperaldosteronism
low K, high Na, high Cl and alkalosis.
Conn’s syndrome
Primary hyperaldosteronism due to adrenal adenoma.
inheritance of congenital rickets
X linked dominant. therefore, males are worse off than females.
Adult onset PCKD
autosomal dominant. Leads to renal failure in 3-4th decade.
Child onset PCKD
Autosomal recessive. Liver and renal impairment, eventually causing portal hypertension and cirrhosis.
Cystinosis
Autosomal recessive. PResents with renal failure but can appear later with failure to thrive, crystals in the cornea and is the most common cause of Fanconi syndrome in pediatric patients. Lysosomal storage disease with increased cysteine. High levels of amino acids and CHO in urine, polyuria and hypokalemia and hypophosphatemia.
diabetes insipitus and electrolytes
Inability to concentrate urine leads to icnrease in both Na and K (hemoconcentration and hypernatremic dehydration).
Cushing Syndrome Types
ACTH dependent (ie cushings disease from pituitary adenoma or from ectopic source) or ACTH independent (adreanl hyperplasia, adrenal adenoma or carcinoma).
Adverse effects of testosterone use
aggressiveness, mood lability, decreased testes size, oligospermia, liver damage, premature closure of epiphyseal plates.
Signs of Bulemia (also the common psych disorder)
Occurs usually mid adolescence. Tooth decay (anterior), erythamtous uvula. Often severe depression.
Some signs of anorexia
profound wt loss (>15%), hirsutism, loss of head hair, bradycardia, cardiac conduction problems. Associated with a more complicated psychiatric picture.
Vomiting metabolic abnormality
hypochloremic hypokalemic metabolic alkalosis
Diarrhea or laxatives metabolic abnormality
acidosis
Most serious complications of anorexia are…
cardiac, representing the greatest mortality risk: long QT (careful with medication choice), arrhythmias, cardiomyopathy, hypotension, bradycardia. Risk is greatest during first two weeks of refeeding when metabolic rate rises.
Thyroid hormone forms
Mostly T4, 5% T3 and a little rT3. Most rT3 is made in the tissues by enzymes.
rT3 increased in ….
sick euthyroid syndrome because of decreased clearance with normal production.
Sick Euthyroid Syndrome
Seen in starvation, critically ill patients and in the ICU. T4 and TSH are normal but total thyroid hormone and unbound T3 are low.
Most common cause of pediatric hyperthyroidism…
Graves disease. TSH receptor stimulating Ig from B cells. Tx: thryoid blocking meds, beta blockers, radioactive Iodine uptake, surgery.
In pregnancy, TSI can cross placenta, leading to transient neonatal thyrotoxicosis (heart failure risk).
Patient with neck pain and demonstrating signs of hypothyroidism after a period of thyrotoxicosis. ESR is high and RIU is low.
Subacute thyroiditis. Usually caused by a virus and happens in epidemics.
Bone disease in prematurity
Most premature babies will have some osteoporosis. Calcium and phosphorus arrive from the mother mostly in the third trimester. Consequently, hypophosphatemic bone disease is common.
Red flags for puberty issues
Wt loss, contrasexual development beforenage 8 in girls and 9 in boys, no secondary characteristics by age 14
Abnormal stature diagnostic criteria
Short:
<3rd percentile, <5cm growth per year
Tall:!greater than 9797%
Short stature ddx
Pathologic: genetic (turner, Noonan, down), hormone deficiencies (thyroid, GH), chronic disease, iatrogenic (steroids)
Normal: constitutional delay , familial short stature.
Tall stature ddx
Familial, constitutional tall
Genetic: marfan, klinefelter
Hormone excess: GH, adrenal
Obesity
Red flags for abnormal growth
Dystrophic features, growth velocity <5cm, precocious puberty
Red flags for ADHD or learning disorders
Neonatal complications, fm hx, neglect or abuse, developmental regression, new or recent onset
Russel silver Syndrome
Imprinting/UPD disorder causing dwarfism. IUGR, SGA, difficulty feeds, hypoglycemia. Triangle head, body asymmetry, clinodactyly, blue tinge to sclera, precocious puberty, late close AF.
The common trisomies
Downs, Patau, and Edwards (21, 13, 18)
Common genetic conditions
Downs, Noonan, fxs, klinefelter, turner
Fragile x syndrome
Most common inherited cause of autism, mental retardation, intellectual disability.
Genetic counselling and prenatal screening should be offered to at risk.
Cause by cag repeats on X chromosome.
Features of FXS
Autism (perseveration, echolalia), developmental delay (sec to hypotonia), ADHD.
Long thin face, prominent ears, facial asymmetry, pes excavatum, scoliosis.
