Is it normal for cortisol to be high normal and acth also be in upper normal range? Shouldn't cortisol be suppressed if acth is raised?
Pic attached of levels. Both taken at same time 9 am.
- Lab GuyLv 61 month ago
You are way out of line with your micro over interpretation.
You have an ACTH of 46 which is within the reference range of normal.
Your cortisol is 21.6 with a stated reference range that is within normal. The reference range takes into account the time of day.
Both are within the reference range. That is all one can say. One does not look at whether it is in the upper part of the reference range and then say it is high.
One excludes statistical variance that includes the normal population. What one is looking for is pathological values outside the reference range. Those are the ones that are clinically significant. It's normal for people to have low or high values within the reference range at large. We are all different which is why we have a reference range.
One way to eliminate such misinterpretations involving the general reference range is to establish with serial testing your own range and seeing if there is on a trend up or down over time.
One does not use blood cortisol levels clinically as you stated with regards to high cortisol levels outside the reference range. Low levels carry more clinical significance. Other tests are needed for detecting primary hypercortisolism inclusive of urinary free cortisol.