Hi le,

17-ketosteroids are substances that are measured in the urine to assess androgen production.  We used to get 24-hour urine collections all the time, though not as much in the recent past. 

For reference ranges:  Dr. Scott Rivkees wrote an article on monitoring CAH for the CARES newsletter a couple of years ago, which talks about urine collections and 17-KS.   To find the article, go to the CARES website and find the tab that says "monitoring CAH."  It should take you to a copy of the article.

Good luck.