Precocious Puberty

1. Epidemiology
   1. Girls: Benign central cause in 50 to 90%
   2. Boys: Pathologic peripheral cause in 50%
2. Definition of Precocious Puberty
   1. Girls
      1. Breast development (modified 1999)
         1. White: Before age 7 years
         2. Black: Before age 6 years
      2. Menarche before age 10 years
      3. Pubic Hair (modified 1999)
         1. White: Before age 7 years
         2. Black: Before age 6 years
      4. Referral recommended if 2 signs at age <8 years
      5. References
         1. Kaplowitz (1999) Pediatrics 104:936-41
         2. Midyett (2003) Pediatrics 111:47-51
   2. Boys
      1. Testes > 2.5 cm (>3 ml vol) before age 9 years
      2. Pubic hair before age 9 years
3. Red Flags suggesting pathologic cause
   1. Premature Puberty in very young children
   2. Contrasexual development
      1. Feminization in boys
      2. Virilization in girls
   3. Peripheral cause (often asynchronous development)
      1. Penis enlarges without scrotal enlargement
      2. Extensive pubic Hair Growth
      3. Menarche without Breast bud development in girls
   4. Precocious Puberty in boys (50% pathologic)
   5. Visual field deficit suggests pituitary mass
4. Causes
   1. See Precocious Puberty Causes
5. Labs (See Evaluation below)
   1. Follicle Stimulating Hormone (FSH)
   2. Luteinizing hormone (LH)
   3. Estradiol Level (in girls)
   4. Testosterone Level (in boys)
   5. Thyroid Stimulating Hormone (TSH)
   6. Serum Human chorionic gonadotropin (HCG)
      1. Screen for gonadotropin secreting tumor
   7. Consider GnRH Stimulation Test
   8. See additional evaluation for Step 2c below
6. Radiology (See Evaluation below)
   1. Left wrist radiograph for bone age
   2. Consider Head MRI
      1. Screen for pituitary or other CNS lesion
   3. See additional evaluation for Step 2c below
7. Evaluation Step 1: Initial Evaluation
   1. Clinical history and physical
   2. Exogenous Sex Hormone sources
      1. Androgens and Anabolic Steroids in boys
      2. Oral Contraceptive use in girls
      3. Estrogen or placental containing hair products
         1. Common use in African American girls
         2. Associated with Breast or pubic hair development
   3. Evaluate Pubertal Milestones (See Tanner Staging)
   4. Evaluate growth chart
   5. Obtain Left Wrist XRay for bone age
8. Evaluation Step 2a: Unremarkable Evaluation in Step 1
   1. Findings
      1. Early, but normal Puberty
         1. Girls: Breasts enlarge early
         2. Boys: Testicles enlarge early
      2. Bone age exceeds chronological age
         1. Early growth spurt and initially taller than peers
         2. Early epiphyseal closure and short in adulthood
   2. Diagnosis
      1. Constitutional or Idiopathic Precocious Puberty
   3. Further evaluation
      1. Observation
      2. Consider further diagnostic testing (see above)
         1. All labs at pubertal levels
         2. All imaging studies normal
   4. Management
      1. Counseling and reassurance
      2. Consider GnRH analog to suppress FSH and LH
         1. Leuprolide (Lupron) long acting injectable
         2. Nafarelin (Synarel) short acting intranasal
9. Evaluation Step 2b: Normal Variation in Step 1
   1. Findings
      1. Early, but normal Puberty
      2. Bone age consistent with chronological age
   2. Diagnosis: Benign Premature Adrenarche
      1. Girls
         1. Benign Premature Thelarche
         2. Benign premature Menarche
      2. Boys
         1. Benign Gynecomastia of Adolescence
         2. Familial Gynecomastia
   3. Further evaluation
      1. Observation
      2. Consider further laboratory testing (see above)
   4. Management
      1. Counseling and reassurance
10. Evaluation Step 2c: Abnormal Evaluation in Step 1
    1. Findings
       1. Abnormal Pubertal Milestone sequence
       2. Bone age variable
          1. May be consistent with chronological age
    2. Differential Diagnosis (pathologic cause suspected)
       1. See Precocious Puberty Causes
    3. Further evaluation
       1. Further laboratory testing (see above)
       2. Additional lab testing (esp. virilization of girls)
          1. 17-Hydroxyprogesterone
          2. Serum Dehydroepiandrosterone (Serum DHEA)
       3. Additional imaging (suspect peripheral cause)
          1. Pelvic Ultrasound of Ovaries
          2. Adrenal CT
    4. Management
       1. Assess for exogenous sex steroid exposure
       2. Treat based on underlying cause
11. References
    1. Blondell (1999) Am Fam Physician 60:209-24
    2. Fahmy (2000) Br J Radiol 73(869):560-7
    3. Foster (1992) Obstet Gynecol Clin North Am 19:59-70
    4. Styne (1997) Pediatr Clin North Am 44(2):505-29
    5. Tiwary (1998) Clin Pediatr 37(12):733-9
    6. Walvoord (1999) Pediatrics 104(4):1010-4