Puberty and Adolescence

What are the 3 components of the Tanner staging method?

(1) B = Breast [1-5]. (2) P = Pubic hair [1-5]. (3) G = genitalia [1-5]. NOTE: 5 = full development, 1 = pre-pubertal].

What are the likely causes of delayed puberty in (1) Boys and (2) Girls?

(1) BOYS = 80% are constitutional maturational delay [one/both parents = Hx of delay - suggests hypothalamic site]. (2) GIRLS = Likely underlying pathology.

What investigation results would you expect to see in True central precocious puberty (TCPP)?

(1) Bone age = >2+ years. (2) Pelvic USS [GIRLS] = Oestrogenised pelvic organs [Ovaries >3ml, several folicles, endometrial stripe, pear-shaped uterus]. (3) Testicular volume >4ml [BOYS]. (4) Measurable oestradiol/Testosterone. (5) LHRH test = Pubertal response (LH peak >5, LH>FSH). (6) MRI Pituitary.

List the 5 important features linked with the initiation of puberty.

(1) Genetic factors. (2) Nutritional status. (3) Exercise. (4) Chronic conditions. (5) Environment.

What are the 5 key tasks of a person's psychosocial development?

(1) Identity. (2) Autonomy. (3) Intimacy. (4) Sexuality. (5) Achievement.

What are some of the important developmental processes that are carried out within the developing adolescent brain?

(1) Strengthening of neuronal connections and elimination of others - Blossoming and Pruning. (2) Myelination [posterior to anterior i.e. Occipital to frontal direction].

What are the two main types of precocious puberty?

(1) True central precocious puberty - Gonadotrophin dependent/central. Normal puberty resulting from activation of the hypothalamus and following a normal sequence BUT EARLIER. (2) Precocious pseudopuberty - gonadotrophin-independent/peripheral. Sexual precocity caused by abnormal secretion of sex steroids independent of hypothalamic-pituitary control.

Define Thelarche.

Isolated breast development in the absence of other symptoms and the absence of signs of sexual precocity. NOTE: Common in infants and pre-school children, sometimes present @ birth.

Define puberty.

It is a series of events associated with a growth spurt and culminating in the acquisition of sexual maturity and reproductive function. THUS, it is the process of gonadal maturation resulting in the acquisition of secondary sexual characteristics, growth spurt and fertility.

Define adolescence.

It is the transition from childhood dependence to adult autonomy [10-24 years]. It embodies the psychological and neurological changes that allow us to survive in the adult world.

Why is the amygdala region of the brain important in adolescence?

It plays a central role in processing of emotions. Decision making is based on emotions rather than reasoned judgment. Due to ongoing development of the prefrontal cortex, behavior is frequently controlled by the amygdala. THUS = Poor judgment, increased risk taking, impulsive/emotional responses.

What is the consonance pattern in girls?

Breast buds followed by pubic hair and growth spurt and later on menstruation. NOTE: Rise in oestrogen required to commence menstruation causes epiphyseal plates to fuse, stopping growth.

What is Congenital adrenal hyperplasia?

Commonest cause of precocious puberty (discordant pattern). Due to defect of cortisol synthesis (usually 21-hydroxylase deficiency). Thus build up of 17-hydroxyprogesterone - shunted to increase in testosterone production! RESULT = Virilisation + high BP + lack of cortisol. Rx = Replacement therapy.

Define consonance and why it is important.

Consonance is the set pattern that puberty typically follows. Any deviation from a consonance pattern suggests an underlying abnormality. Consonance and non-consonance allows the identification of the site that is driving the physical changes.

What is delayed puberty?

GIRLS = Absence of breast development in a girl by the age of 13.5 years, or where puberty is incomplete, in that menstruation has not occurred within 3 years of breast formation. BOYS = Failure of testicular growth >4mls by 14 years.

Describe the roles of the various hormones in male puberty.

GnRH = secreted by the hypothalamus, stimulates the pituitary gland to release LH then FSH. LH = testes to produce testosterone. FSH = promotes spermatogenesis [so testes enlarge]. Adrenal hormones = pubic and axillary hair.

Describe the roles of the various hormones in female puberty.

GnRH = secreted by the hypothalamus, stimulates the pituitary gland to release LH then FSH. Oestradiol and Progesterone = Produced by the Theca Granulosa cells of the ovaries. Oestrogen produces brest development/fat deposition @ hips/increased uterus and vagina size and secretions. Adrenal hormones = pubic and axillary hair.

List 2 investigations that may be useful in cases of pubertal problems.

INCLUDING: (1) Hormone levels [FSH/LH/Oestrogen/Testosterone/adrenal hormone levels]. (2) Karyotyping. (3) Bone age. (4) Pelvic USS. (5) CT/MRI cranium. NOTE: FSH>LH if prepubertal, and LH <5. If pubertal, LH>FSH and LH >5.

What might be learned from either a consonance or non-consonance pattern occurring in precocious puberty?

If CONSONANCE = a problem w/ the hypothalamic-pituitary-gonadal axis is probable. If NON-CONSONANCE = gonadal/adrenal problem is likely.

Define Gonadarche.

The onset of puberty, heralded by an increase in nocturnal secretion of GnRH towards the end of the 1st decade leading to an increase in LH and FSH secretion from the pituitary gland, thus increasing Testosterone (MALES) and Oestrogen (FEMALES) from the gonads.

How do adolescents differ in their ability to read emotions in comparison to adults?

Their Frontal lobes are less developed than adult frontal lobes. Thus they have a lessened ability to hypothesise, plan ahead, analyse and logically reason. Furthermore, they use less of their prefrontal region than adults when reading emotions. They tend to use the amygdala region. THUS = Miscommunication with peers and adults, they miss subtle social cues, misinterpret expectations and misread facial expressions.

Define Adrenarche.

This is a normal physiological activity that occurs approximately 1 year before puberty (~6-8yrs). Due to an increase in adrenal hormone output (LH/FSH independent). Causes axillary hair [small amount of pubic hair] development and body odour

What is the Rx of TCPP?

Regular administration of GnRH analogue - suppresses/inhibits LH and FSH secretion by negative feedback to the hypothalamus. STOP AT AGE 11-12 [prevent future damage to bone health]. Menses = approx 12-18 months after Rx stopped.

What is the consonance pattern in boys?

Testicular growth (>4mls) followed by penile growth w/ pubic hair and then a growth spurt [occurs in late puberty, w/ a testicular volume of 10-12 mls].

Define precocious puberty.

The development of puberty in a girl before age 8 and age 9 in boys. NOTE: It is idiopathic in 90% of GIRLS, but pathological in 60% of BOYS.