Puberty and precocious puberty (DOW) Flashcards
Thelarche
is the appearance of breast tissue
Usually the first and most obvious sign of early puberty in girls
Adrenarche
is the activation of the adrenal cortex for the production of adrenal androgens, and typically occurs before the onset of puberty.
Pubic and axillary hair may appear before, at about the same time, or well after the appearance of breast tissue
Mini-puberty of infancy
The hypothalamic-pituitary-gonadal axis is biologically active in infancy with peak activity between six and eight weeks of age. This state yields sex steroid levels comparable with those seen in early-to-mid puberty, but without peripheral effects.
Hormonal changes after birth: falling levels of maternal estrogens
65-90% of neonates have breast tissue
Vaginal discharge can be observed.
“Witches’ milk” from breasts and even menses can be seen
* Neonatal acne - usually just comedonal in nature- also common (infantile can also develop)
Suppression of HPA in puberty
Suppression of hypothalamic-pituitary-gonadal axis is released;
Secretion of high-amplitude pulses of gonadotropin-releasing hormone (GnRH) by the hypothalamus
Pulsatile increases in the pituitary gonadotropin-luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
Increased LH levels stimulate production of sex steroids by testicular Leydig cells or ovarian granulosa cells.
androgens in puberty
Androgens or estrogens at pubertal levels cause the physical changes of puberty
Penile enlargement and sexual hair in boys
Breast development in girls, sexual hair
Pubertal growth spurt.
FSH and puberty
Increased FSH levels cause enlargement of the gonads in both sexes and eventually promote follicular maturation in girls and spermatogenesis in boys.
genetics and pubertal timing
African American girls begin puberty earlier than Caucasian girls.
Puberty Related Issues
anemia gynecomastia acne psychological correlates of puberty some sports-related injuries myopia scoliosis STIs dysfunctional uterine bleeding
testicular volume and puberty
: early sign of puberty: testicular length is more than 2.5 cm or testicular volume (with Prader orchidometer beads) is 4 mL or more
Tanner breast bud stage
stage 2
3- curvy no pokey thing
4- pokey like the number 4
Boys’ external genitalia stage 2
Enlargement of scrotum and testes;
Precocious Puberty
Puberty before
Age 8 for girls
Age 9 for boys
bone maturation and precocious puberty
Early growth spurt initially can cause tall stature, but rapid bone maturation (premature and rapid skeletal maturation and fusion of the epiphyses) can cause linear growth to cease too early and can result in short adult stature
Evaluate with bone age
Incomplete Precocious Puberty Classification
Premature pubarche and premature thelarche are two common, benign, normal variant conditions that can resemble precocious puberty but are nonprogressive or very slowly progressive.
Premature thelarche refers to the isolated appearance of breast development, usually in girls younger than 3 years;
Premature adrenarche (=pubarche) refers to appearance of pubic hair without other signs of puberty in girls or boys younger than 7-8 years (usually progression is slow, so ultimate height is okay).
central vs peripheral precocious puberty
Central Precocious Puberty (CPP)
= Gonadotropin Dependent Precocious Puberty (GDPP)
= True Precocious Puberty
Peripheral Precocious Puberty
= Gonadotropin Independent (GIPP)
= Pseudoprecocious Puberty
Central Precocious Puberty- CNS abnormalities and thyroid
hypothalamic hamartomas
Hamartomas of the tuber cinereum are benign tumors that are the most frequent type of CNS tumor to cause precocious puberty in very young children
These secrete GnRH
Tumors (eg, astrocytomas, gliomas, pinealomas, ependymomas)
Acquired CNS injury caused by inflammation, surgery, trauma, radiation therapy, or abscess
Severe, prolonged primary hypothyroidism can cause precocious puberty
how to distinguish central from peripheral precocious puberty
Central precocious puberty can be distinguished from peripheral precocious puberty by measuring LH levels.
In central precocious puberty (GDPP), basal LH levels are often elevated into the pubertal range and show a pubertal (heightened) response to GnRH stimulation.
In peripheral precocious puberty (GIPP), the LH level is low at baseline and fails to respond to GnRH stimulation.
Precocious Puberty in Girls -Findings
Breast enlargement
* Usually the first and most obvious sign of early puberty is usually which may initially be unilateral.
The most reliable sign of increased estrogen production is breast enlargement.
Distinguishing glandular breast tissue from fat, which can mimic true breast tissue, is essential. Examining the patient while she is in the supine position usually minimizes the chance of misinterpreting fat as true breast enlargement.
- Pubic and axillary hair may appear before, at about the same time, or well after the appearance of breast tissue.
enlargement of the clitoris
clitoris indicates significant androgen excess that must be promptly evaluated.
Precocious Puberty in Boys -Findings
The earliest sign of central precocious puberty (CPP) is enlargement of the testes, which depends on increased production of follicle-stimulating hormone (FSH); testicular length is more than 2.5 cm or testicular volume (with Prader orchidometer beads) is 4 mL or more*
most common cause of peripheral precocious puberty in girls
Large functioning follicular cyst of the ovaries
McCune-Albright Syndrome
2 of the following 3 features:
Polyostotic fibrous dysplasia
Café-au-lait skin pigmentation
Autonomous endocrine hyperfunction
Other endocrine syndromes including hyperthyroidism, acromegaly, and Cushing syndrome
important part of the history with precocious puberty
neurologic:
CNS risk factors, including infections, perinatal asphyxia, head trauma, neoplasms, or prior radiation therapy
Personality changes, increased appetite, headaches, seizures, and/or visual changes
Androgenic effects:
Acne, hirsutism, increased muscle mass, and clitoromegaly in females will focus the differential diagnosis toward androgenic causes of precocious puberty.
important workup and labs for precocious puberty
Initial work up may include bone age (radiograph of the nondominant hand and wrist)
In GDPP (central), basal LH levels are often elevated into the pubertal range and show a pubertal (heightened) response to GnRH stimulation. In GIPP, the LH level is low at baseline and fails to respond to GnRH stimulation.
MRI of the head for precocious puberty
The younger the child with central precocious puberty, the greater the chance of finding CNS pathology (among children younger than 6 years).
For boys younger than 9 years, the incidence of CNS findings is much higher than in girls, and MRI should be part of the evaluation.
Treatment: Central Precocious Puberty
GnRH analogs or agonists
Example: Leuprolide
Increases final adult height
Treatment: Peripheral Precocious Puberty
Does not respond to GnRH agonist therapy
Tumors of the testis, adrenal gland, and ovary: surgical management
most frequent type of CNS tumor to cause precocious puberty in very young children
hypothalamic hamartoma
Hypothalamic Hamartoma - associated stuff
Classically a triad of precocious puberty, developmental delay, and seizures
cause intractable epilepsy with frequent gelastic and other mixed seizure types, intellectual disability, behavioral disturbance with severe temper tantrums, and precocious puberty.