Yes, this happened with my son too, luckily we changed to an excellent paediatric endocrinologist, who believed my son. During puberty it seems the clearance rate of hydrocortisone can increase, which is why the hydrocortisone does not last long enough in the system to suppress the 17 OHP. You can read an article written by Professor Hindmarsh and my son.
It might be that smaller more regular doses of hydrocortisone are needed, this can be established by having a full 24 hour blood profile, with hourly or two hourly samples taken for 17 OHP and cortisol. This shows when the cortisol is running low and the times the control is being lost as the 17 OHP will rise. It also shows how much cortisol you are getting from the dose of hydrocortisone.
My son had terrible side effects when he tried dex, which he also metabolised quickly. I can understand how upset you feel, and I hope that you can find a doctor who listens and believes you, I most certainly do!!!
Professor Hindmarsh explains in the article
Poor control in young people with congenital adrenal hyperplasia is often observed in adolescence because in part the handling of hydrocortisone by the body changes and it is removed more quickly from the circulation. This can lead to problems with getting the right dose for the individual.
I hope this helps, good luck!
Kathy
