advanced bone age

My son is 10 years old and has fallen from the 50th percentile for height to the 20th percentile in the last few years.  I was concerned so the pediatrician did a bone xray expecting it to be delayed.  The xray showed a bone age of 11.  For his bone age, he would only be in the 5th percentile!  We went to a ped. endo. and the initial blood tests (thyroid, IgF-1,celiacs) were within normal.  The Dr. thought he is probably a late bloomer.  From what I have read, late bloomers have delayed bone age, not advanced, so I am not sold on this.  He does not yet have signs of puberty.  He has not had the GH stim test yet.  What would cause his bone age to advance if he is not yet in puberty?  He is not heavy.  If he has ISS and a normal growth hormone test, would growth hormone therapy still help?  What other tests should I have done?  

[Deanna L Aftab Guy, MD]

Yes, usually late bloomers do have delayed bone ages but we are fooled at times and a child can exhibit catch up growth later with no delayed bone age being noted initially, hence the reason that we follow these kids closely, the adrenal gland may have kicked in to allow normal bone development, his bones are not advanced, rather bone age of 11 is more than likely upper limit of normal, also overweight can drive the bone age to be advancing more rapidly. but you mention he is not heavy. Stick with your ped endo every 4 months, the growth velocity needs monitored and then they can consider need for gh stim testing, also plotting his height against yours and dads is key and look at this projection with the peds endo.

[pb143]

A related discussion, What happens now after Lupron? was started.

[huggi170]

A related discussion, advance one age for 7year old was started.

[weltin]

A related discussion, advanced bone age was started.