True precocious puberty is idiopathic in 90% of female cases, and in 50 to 60% of male cases.
- true precocious puberty (characterized by breast and pubic hair development in girls, or testicular enlargement in boys) occurs in approximately 1 in 5000 children and is five to six times more common in girls than boys
- in most affected girls (80-90%), but in only half of the affected boys, precocious puberty is gonadotropin-dependent and idiopathic in nature
In other cases the investigator would tend to look for a central cause, including:
- central nervous system tumors or lesions
- CNS lesions may be hamartomas, pineal, dysgerminomas, and neurofibromatosis
- note that tumours of the pituitary gland do not as a rule cause precocious puberty; instead they are more likely to result in deficiency states
Other possible associations include:
- cerebral palsy
- recurrent seizure disorders
- after meningitis or encephalitis
- after head trauma or radiation injury
- internal hydrocephalus
Notes:
- less commonly precocious puberty is gonadotropin independent and may include testotoxicosis (male limited with premature Leydig and germ cell maturation), gonadal, or adrenal steroid-producing tumors, and McCune-Albright syndrome.
- McCune Allbright syndrome
- affected tissues in patients with McCune-Albright syndrome have a mutation of the G3a subunit of the G3 protein that activates adenylate cyclase
- this activating mutation leads to continued stimulation of endocrine function, eg, precocious puberty
- central nervous system tumors or lesions are much more common in boys
Reference:
- (1) Saenger P, Rincon M.Precocious puberty: McCune-Albright syndrome and beyond.J Pediatr. 2003 Jul;143(1):9-10.