Does My Patient Have Precocious Puberty? Part Two
If you haven’t read my last entry, please read it before reading this one.
Case History One
You are a busy pediatrician. You are seeing Susie, a 7 year-old-girl who has been followed by you since her birth. She has been generally quite healthy, with normal growth and development. The clinic visit was a routine 7-year-old check-up. Her parents mentioned that over the past few months they have noticed that she has had started having body odor, especially after sports activities. What should you do?
First, this is a very common situation in general pediatric practice. I would start out by getting a complete medical history and performing a physical examination, including a sexual examination- breast exam, underarm exam, and genital examination. Let us assume that there is no family history of precocious puberty and that Susie is not taking any medications except vitamins (this includes no health food store supplements, etc.). She has no history of exposure to topical androgen-containing creams or lotions. Her physical examination is normal; her height and weight are at the 60th percentile, the same as the year before. She has no breast development, but she does have some axillary odor and a bit of axillary hair (an easy way to tell if a child has axillary apocrine gland activation is to just to feel the underarm skin. If it feels “roughened,” the child has axillary gland activation; prepubertal children normally have smooth and dry underarms). Her genital examination was normal- no clitoral enlargement, no labial fusion, and red/shiny vaginal mucosa (this means, no estrogen effects).
So, what are the possibilities? By definition, Susie has precocious puberty. She could have premature adrenarche. This condition is caused by early, but otherwise normal pubertal adrenarche. It is not associated with any genital abnormalities, other than maybe pubic hair. Usually, it is not associated with a growth spurt.
What should you do? You could get a bone age, but it probably won’t help; in premature adrenarche, the bone age might be advanced a bit, so you might not learn anything from the x-ray. But, a hand x-ray isn’t dangerous and it is inexpensive, so order one if you are so inclined. If I had told you Susie had a significant growth spurt, I would definitely order a bone age. I would also order some blood work; a serum DHEA-S (more useful than serum DHA or DHEA), serum testosterone, and maybe a serum gonadotropins (LH and FSH). If Susie has premature adrenarche, her DHEA-S would probably be elevated, but not greater than to a normal pubertal level. I probably wouldn’t bother with the serum LH and FSH levels, since she had no breast changes; if she did have breast changes in addition to the axillary odor and hair, I would have expected to also see evidence of estrogen effects on the vaginal mucosa (i.e., pink and dull, rather than red and shiny).
The adrenarche and gonadarche would suggest “true” puberty on a central basis: hypothalamic stimulation of the pituitary gland by gonadotropin-releasing hormone (GnRh), and then pitutary LH and FSH stimulation of the ovaries. There would also be adrenarche- activation of adrenal cortex androgen synthesis.
Back to Susie. If her physical examination is normal except for the axillary odor and hair, and if she did not show evidence of a growth spurt, I would probably wouldn’t order any tests, but plan see her for follow-up in a few months. I would also discuss my recommendations with both Susie and her parents. I would tell them that Susie probably just has a benign pubertal variant called premature adrenarche, but that you would like to see her back every three months or so to be sure the adrenarche is is not the first sign of true puberty or some other condition associated with early adrenarche (e.g.,late-onset congenital adrenal hyperplasia).
In my next entry, we will discuss another case history, in which the child does have breast development along with adrenarche.