The motto of the story is.......don't do blood tests unless you're going to act on them
or they are likely reveal something meaningful.
AME is correct. It's likely to be an incidental finding. If I tested the blood of all pprune'ers hard enough, I'd probably find something "abnormal" in most of them.
Doesn't mean to say your ill, or are going to get ill,as every good doc&nurse knows, its more important to look at the patient in front of you.