180
- What is the importance of age in the etiological diagnosis of precocious
puberty?
Onset of puberty during infancy, particularly in a girl, is usually due to McCune–
Albright syndrome. Majority of children with GDPP due to hypothalamic ham-
artoma present between 2 and 4 years of age. Children with congenital adrenal
hyperplasia and adrenal virilizing tumors may manifest with premature
pubarche at 3–5 years of age. Fifty percent of children with idiopathic GDPP
manifest between 6 and 8 years of age, while 25 % between 2 and 6 years and
18 % during infancy. Precocious puberty due to other CNS pathology, ovarian
cyst, and hypothyroidism may present at any age (<8 years and <9 years in girls
and boys, respectively).
19 What are the causes of precocious puberty associated with decreased growth
velocity?
Precocious puberty is usually associated with increased growth velocity as sex
steroids potentiate “pubertal GH surge” and promote hepatic and local IGF1
generation. However, disorders like primary hypothyroidism, radiation- induced
GDPP, coexisting isolated growth hormone deficiency, and malnutrition are
associated with reduced growth velocity and retarded bone age, despite preco-
cious puberty. Further, overzealous treatment with GnRH agonist for GDPP
can also result in decreased growth velocity.
abFig. 6.3 A 6-year-old girl presented with thelarche. She also had features of thyrotoxicosis. Note
the presence of (a) facial asymmetry (due to fibrous dysplasia), (b) goiter, and café-au-lait macule
over abdomen and chest wall
6 Precocious Puberty