Yes I was treated as a teenager for low immune system with Gammagobulin shots.
I think this has a huge impact on tests but many Doctors are not educated on it. I think when I show a elevated anything it means it is really high. I am what you call a non responder to vaccines also. Hep B series twice and my titre will not rise, small pox given 6 times as a child and no scar or no reaction at all?????? I stay clear of vaccines.
I am going to see what my new Rheumatologist has to say...I am on his waiting list to be seen. Referred there by my Immunologist.
Good luck and I will let you know what I find out......Oleander