Serum Igg Question

[Brit1612]

So sorry to have to start yet another thread, but I am pretty sure y'all will have some insight for me on this one..... (by the way, sweat test results will hopefully be here today)

 

After talking to the nurse and her re-assuring me that "everything was normal, except his low iga", I requested a copy of his results.  I was pretty suprised to notice that his serum IGG said it was low.  It has only been tested once before and was at the lower end of normal that time.  His number was a 513 (at almost 2.5 years old) and it said that the reference range was 533-..... (can't remember the upper limit).

 

Two Questions:

 

1.) Would a low IGG affect his igg based celiac test?  You here a lot about low Iga affecting results, but not much about the IGG.  (He is IGA deficient also)

 

2.)  I am pretty sure the answer to number 1 is yes..... So how low is low?  Since he was very close to normal is this even significant?  I understand that maybe if his ttg igg had been like a 6 or something, maybe it would have skewed the results, but he went from being a 15 on that test to a <.8 (or something to that effect).

 

 

Also, this time his IGM was "normal" but last time is was low as well.  So at one point or another he has been low in IGA, IGM and IGG (but never at the same time).  Should I be concerned more about his immune system?  Are these variations in results common?

 

Thanks in advance for all the support y'all consistently give!  Could our situation possibly get any more confusing / complicated??!!

[nvsmom]

Low IgG would affect his IgG based celiac tests.  If he passes into the deficient numbers, that will affect tests, and I am guessing that a low normal could affect them too.  

 

I'm not sure of the typical lab normals, but there are some listed out there like this one: Open Original Shared Link I imagine it can vary a bit between labs.

 

Low immunoglobulins can be a sign of common variable immunodeficency disorder (CVID).  I think people with this have low Immuglobulins, and not just low normal.  I know someone around here has CVID, but I can't remember who. This was the diagnostic signs in the above link:

 

Diagnosis

Laboratory studies

In patients with CVID, laboratory studies can reveal the following:

• Serum IgA and IgG levels - Decreased (not absent)
• Serum IgM levels - Decreased (occasionally)
• Circulating T and B lymphocytes - Can be assessed by using monoclonal antibodies for immunofluorescence staining
• T-cell function - In vivo measurement is possible by using an anergy panel to assess localized immunologic skin responses

[Brit1612]

Thanks for the information, you are always so helpful.  I googled and looked at numerous "normal reference ranges" and they all seem different.  Some of them have him being low (out of range) an some of them have him being normal on the lower end of the range.

 

I am just having a hard time understanding why he has those positive ttg igg test (twice - once on gluten, once off) and now has had two <.08 results (again once off gluten and once on).  When I saw the lower number on the IGG it just made me wonder even more!  Sorry to be such a bother all the time.  It is just so hard to have such mixed answers with everything!

[nvsmom]

Never a bother.  Questions asked here may go on to help others in the future who, like you, have been given a tough path to follow.

 

It sounds like you'll need to get the normal range from his lab so you know for sure what the range for him is.

 

Did they happen to test IgG when they tested his tTG IgG?  If the IgG was going up that time (but I don't think it fluctuates too much) that could have accounted for some of his variations. 

 

Hang in there.

[Brit1612]

Thanks for the encouragment .  I do have the range that was given by my lab.....It was 533 - something high.  His number this time was a 513.  He only had it tested once before and I believe it was a 566 then.  I just wasn't sure if I should be trusting this range or if he is really ok with this number.  So many of the other ranges were much lower for a 2 year old.  No they did not test it then.  His first ttg igg was a 7.5 (weak positive) and his second one (while gluten free) was a 15.  (clear positive)  Now he is not only negative but is at the very bottom of the range.....so confusing!!!