Precocious Puberty + Premature thelarche/ adrenarche/ menarche Flashcards
Define precocious puberty
Development of secondary sexual characteristics before 8y in F and 9y in M
What are the subtypes of precocious puberty?
- Gonadotrophin dependent (‘central’, ‘true’): premature activation of the hypothalamic-pituitary-gonadal axis
FSH + LH raised - Gonadotrophin independent (‘pseudo’, ‘false’)
due to excess sex hormones
FSH + LH low - Benign/ non-progressive
What is the pattern of development in gonadotrophin dependent and independent precocious puberty?
Dependent: same as in normal puberty
Independent: does not follow pattern of normal puberty
What is the aetiology of gonadotrophin DEPENDENT precocious puberty?
Idiopathic in 90% females
CNS tumour
Genetics
What is the aetiology of gonadotrophin INDEPENDENT precocious puberty?
Females: Ovarian cysts + Ovarian tumours
Males: Leydig cell tumours, hCG secreting germ-cell tumors, familial male limited precocious puberty
Both: primary hypothyroidism, exogenous sex steroids, adrenal pathology (CAH), McCune Albright syndrome
What triad characterises McCune Albright syndrome?
Peripheral precocious puberty
Irregular café-au-lait spots
Fibrous dysplasia of the bones
What are the female breast changes in Tanner stages of puberty?
- Prepubertal
- Breast bud
- Juvenile smooth contour
- Areola/nipple project above breast
- Same shape nipple and breast
How is precocious puberty identified?
Tanner staging
What is Tanner staging?
2 independent criteria:
the appearance of pubic hair in both sexes;
+
increase in testicular volume + penile size + length in males
OR
breast development in females
What should be examined in precocious puberty?
Height, Weight + BMI: early accelerated growth in PP
Assess visual fields: CNS tumour
Examine for Cafe-au-lait spots: neurofibromatosis or McCune-Albright
What is indicated by Testes in precocious puberty?
Bilateral enlargement = gonadotrophin release from intracranial lesion
Unilateral enlargement = gonadal tumour
Small testes = adrenal cause
What investigations can be performed in precocious puberty?
Bloods: LH, FSH, Oestradiol +/or Testosterone
Bone age: Wrist X-ray
Brain MRI
Pelvic MRI: ovarian cysts/ tumour
What is treatment for central precocious puberty?
GnRH agonist: results in initial transient stimulation of gonadotropin secretion from pituitary, followed by complete, but reversible suppression of pituitary-gonadal axis
What test can distinguish central from peripheral precocious puberty?
Gonadotropin-releasing hormone (GnRH) stimulation test
Measure LH, FSH, Oestradiol +/or Testosterone
Administer GnRH/ analogue
Measure LH at 30-60 mins
Define premature thelarche/adrenarche/menarche.
Early partial sexual development, often characterised by transient and minimal pubertal development in the absence of other stigmata of puberty.
Define premature thelarche.
Isolated development of the breasts in infancy
Uni-/ bilateral enlargement
May occur physiologically between 6m- 2y.
Non-progressive + not a/w areolar development.
Define isolated premature menarche.
Premature vaginal bleeding.
Summarise the epidemiology of premature thelarche.
Relatively common in girls <2y of age.
Summarise the epidemiology of isolated premature menarche.
Uncommon.
What is the management for premature thelarche/adrenarch/menarche?
Referral to specialist paediatric endocrinologist.
Name a GnRH agonist
Leuprolide
Name an aromatase inhibitor
Letrozole
