Disorders of Pubertal Development: Precocious Puberty

Precocious puberty is defined as the onset of secondary sexual characteristics before 9 years in boys, at a chronological age 2–2.5 SD before the mean age of pubertal onset for Caucasian population. Upon the underlying pathologic process, precocious puberty can be classified as follows: (1) central precocious puberty (also known as gonadotropin-dependent precocious puberty) due to early maturation of the hypothalamic-pituitary-gonadal axis; (2) peripheral precocious puberty (also known as gonadotropin-independent precocious puberty), caused by excess secretion of sex hormones from the gonads or adrenal glands, exogenous sources of sex steroids, or ectopic production of gonadotropin from a germ cell tumor; and (3) benign pubertal variants, including nonprogressive or intermittently progressive central precocious puberty or isolated androgen-mediated sexual characteristics (such as pubic and/or axillary hair, acne, and apocrine odor) in boys that result from early activation of the hypothalamic-pituitary-adrenal axis (premature adrenarche). Both of these disorders can be a variant of normal puberty.The evaluation is warranted in boys suspected for precocious puberty, beginning with a medical history and physical examination. In most cases, radiographic measurement of bone age (by Greulich and Pyle or Tanner TW2 or TW3 atlas) is performed to determine whether there is a corresponding increase in epiphyseal maturation. Further laboratory and imaging investigations are needed to identify the cause of precocious puberty.The assessment and management of precocious puberty still remain challenging for pediatric endocrinologists. In this chapter, we describe the diagnostic pathway that leads to an adequate treatment of this disorder.