Blood tests and IVIG

I have recently started IVIG treatments. Finished my first round and now am scheduled for blood tests for another physician. Is it important to notify the lab running the tests that I am getting IVIG. Does it affect the results?


ps: Looking forward to learning more about this CIDP.

Hi, The lab probably doesn't need to know that--and if they do, the doctor ordering them should communicate that to the lab.


I'm not sure if you were concerned about IVIG affecting your test results but IVIG can alter blood tests and physicians are not always aware of this issue. It is best to have your blood drawn for testing before you receive IVIG as most of the IVIG will be out of your system and your doctor will get the best information.

For one example of how IVIG can alter blood tests, see IVIG-- A Hemolytic Culprit in the New England Journal of Medicine here Dr. Pintova et al. discuss two cases in which IVIG lead to false positives on blood tests. Secondly, see the patient information page for Privigen and note the language: "Passive transfer of antibodies may confound serological testing."

However, you should not need to inform the lab of such issues. Rather, just ensure that your doctor is aware of the issue.

We have found that when my son has bloodwork that needs to be done we wait until the day before his IVIG treatment to have it done since most of the IVIG is then out of his system. His tests when the IVIG is in him fully are affected. Especially the Hemoglobin.

Thanks for all the answers. It's important that we share experiences on this site!

I found out that I have anemia most likely caused by my CIDP. It's not caused by the IViG. I have to take daily iron pills with Vitamin C.
bbirder said:

Thanks for all the answers. It's important that we share experiences on this site!