Step I Mult. Myeloma

[Cristagali]

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FA says IgG is increased significantly in MM. However, Robbins says IgG is decreased, which makes the patient susceptible to encapsulated bacteria. Is the IgG increased, but faulty?? Or maybe I'm just not getting it. Any input appreciated. Thanks 😀

 

[csmith1]

Methinks that a monoclonal and pathologic IgG- or IgA-producing line of lympocytes will be VERY high (the M protein!), but overall, normal IgG that can protect against infection will be low. The normal lymphocytes (and other marrow components) will be crowded out by the pathologic monoclonal line. But please, don't take my word for it.

 

[Cristagali]

yeah, I think you are right. yes, there is an increase in the monoclonal patho IgG, but still a decreased function, hence, increased risk to certain infections, (implied that normal IgG is decreased and overwhelmed) Thanks for the input. 😎

 

[inositide]

agree w/ above. monoclonal expansion of a single plasma cell line will produce IgG with singular antigen specificity. It will also depress normal production of IgM, IgG, IgA etc, therefore reducing the humoral immune response to new antigenic challenge.

 

[CaptainZero]

I definitely agree w/above...for what it's worth at this point

 

[csmith1]

I, too, would like to agree with my original post 😉 (which is always easier to do with validation).

 

[Idiopathic]

Actually, you could have really 😉 kick-ass humoral response to that one antigen

 

[bonefixr]

The other thing to think of too is that most of the time the antibody produced in MM is just the light chain fragment and not necessarily the entire, complete IgG. However, when doing the electrophoresis it shows up as the IgG spike even though the protein is not complete.