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PRECOCIOUS PUBERTY & DELAYED PUBERTY

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STAGES OF PUBERTY

  1. accelerated growth
  2. thelarche (breast budding)
  3. pubarche and adrenarche (growth of pubic and axillary hair)
  4. maximal growth (peak height velocity)
  5. menarche
    • Tanner Staging

PRECOCIOUS PUBERTY


Definition

 

  1. onset of puberty before age eight
  2. 1/10,000 incidence


Isosexual Precocious Puberty 

 

  1. sexual maturation appropriate to genotypic sex of individual
  2. true vs. pseudopuberty
  3. due to increased gonadotropin production secondary to premature activation of hypothalamic-pituitary-gonadal axis (HPG-A)
  4. normal adult hormone levels with development of all secondary sexual characteristics

 

Classification of Isosexual Precocious Puberty

Constitutional (90%)

  1. Idiopathic premature activation of
  2. HPG-A
  3. F:M = 5:1

Central (10%)

  1. Tumour,obstructivelesion,granulomatousdisease,infection,neurofibromatosis, head trauma
  2. All interfere with normal inhibition  of hypothalamic GnRH release

Diagnosis

  1. obtain LH and FSH levels
    • if increased ---> central pathology
    • if low/normal ---> exogenous estrogen
  2. TSH, DHEAS
  3. bone age
  4. CT scan

 

Treatment

  1. GnRH agonist (Lupron) (negative feedback to downregulate GnRH receptors)


Heterosexual Precocious Puberty

 

  1. development of secondary sexual characteristics opposite to genotypic sex
  2. e.g. virilizing tumour (ovarian, adrenal), congenital adrenal hyperplasia,exogenous androgen exposure

    DELAYED PUBERTY


    Definition

     

    1. absence of normal pubertal events at an age 2.5 SD from the mean
      • absence of thelarche by age 13
      • absence of menarche by age 15

    Etiology

     

    Ovarian failure

    1. hypergonadotropic hypogonadism
    2. +/- abnormal karyotype (e.g. Turner syndrome 45 X0)

     

    Hypothalamic, pituitary failure

    1. hypogonadotropic hypogonadism
    2. reversible: physiological delay, weight loss/anorexia
    3. irreversible: GnRH deficiency, hypopituitarism

     

    Outlet sydromes

    1. eugonadism
    2. vaginal septum, imperforate hymen

    Diagnosis

     

    1. history
    2. previous height and weight charts
    3. pubertal milestones of siblings and parents
    4. physical (including height and weight)
    5. Tanner staging
    6. rule out anatomical abnormalities (i.e. U/S)
    7. serum gonadotropins
    8. bone age
    9. skull films
    PRECOCIOUS PUBERTY & DELAYED PUBERTY PRECOCIOUS PUBERTY & DELAYED PUBERTY Reviewed by Radiology Madeeasy on August 22, 2010 Rating: 5
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