Thanks Carol, your explanation is very reasonable but my initial question still stands.  Suppose it’s really not the ACTH that will determine how a child presents but renin and electrolyte (what is considered high enough for a doctor to disclose a newborn up to toddler age as a salt waster) doctors will still have a problem to figure out how a newborn baby girl presents because of the prenatal Dex treatment that probably affects all levels involved.  How do they do it than?  Also why is an ACTH stim test so much in the circulation if it really doesn’t serve the purpose for what doctors usually use it?

A