8 year and 4 month old Black female patient who presented as a new patient to my office for a wellness exam. Mom reported that she has been healthy and developing normally, with no chronic diseases. Mom expressed concern that the patient has had pubic hair growth since 6 years of age, and breast budding in the same time frame. She now has axillary hair as well as pubic hair. She has not had any vaginal bleeding. On the exam, her height is 58” (99th percentile), weight is 85.2 lbs (96th percentile), BMI 79th percentile, and BP 101/54. Exam was unremarkable except for Tanner 3 pubic hair and mature axillary hair. She has the appearance of breast development which on exam seems to be breast budding with some adipose tissue as opposed to all breast tissue. She does not have signs of virilization.
I appreciate guidance on the planned work-up for this patient. Thank you in advance.
Thanks for the consult. I agree with your plan. We recommend evaluation in children presenting with secondary sexual development younger than eight years in girls or nine years in boys.
The etiology of precocious puberty is classified by the underlying pathogenesis into the following categories:
- Central precocious puberty (CPP) is caused by early activation of the hypothalamic-pituitary-gonadal axis. CPP is pathologic in up to 40 to 75 percent of boys and 10 to 20 percent of girls.
- Peripheral precocity is caused by secretion of sex hormones either from the gonads or adrenal glands, ectopic human chorionic gonadotropin (hCG) production by a germ-cell tumor, or by exogenous sources of sex steroids and is independent of the hypothalamic-pituitary-gonadal axis.
The first step in the laboratory evaluation of progressive development of precocious secondary sexual characteristics is to measure basal luteinizing hormone (LH), follicle-stimulating hormone (FSH), and either estradiol. Keep in mind that these need to be early morning labs. The results are used to differentiate between CPP and peripheral precocity, which then guides additional testing.
In CPP, basal LH levels are often elevated into the pubertal range (greater than 0.2 to 0.3 mIU/mL, depending on the assay)
LH concentrations in the prepubertal range (ie, <0.2 mIU/mL) are consistent with either peripheral precocity or a benign pubertal variant such as premature thelarche
Recommendations for imaging depend on the type of precocious puberty While all girls with the onset of CPP below the age of six years should also have contrast-enhanced brain magnetic resonance imaging (MRI), there is ongoing controversy about the need for more routine imaging of girls between the ages of six and eight years. In summary, I will start with early morning evaluation as well as bone age. Based on the results, further management can be decided. The only permanent physical complication of a true isosexual precocious puberty is short adult life, as excessive sex hormone production in the first decade of life causes early maturation of epiphysis resulting in premature closure, and treatment is only recommended if sexual precocity is rapidly compromising height potential or results in important secondary emotional disturbance in the child. I hope this is helpful!