Q:

10/9/2012
I have a 36 year old male with a history of chronic sinusitis who has received multiple courses of antibiotics throughout the year. The patient has even undergone FESS x 2 with limited improvement. I sent him for serologic evaluation of his immune system. The first blood draw was a "lipemic specimen" to the point where he had to return to get his blood redrawn. The second attempt showed the following:

IgG of 115 mg/dL, IgM 7 and IgA <7

All were very low.

Pneumococcal titers also obtained at the same time were all non-protective in all 14 serotypes.

Our lab supervisor says that perhaps the antibody studies may be influenced by high lipids. The patient has fairly high triglycerides at 563 (normal <130) and a VLDL at 113 (normal<31).

So my question is how reliable are these antibody lab values in light of the lipidemia? I have tried to find the answers, but to no avail.

Also, what do we do in these situations where we suspect there may be an immune dysfunction? My current plan is to have the patient on lipid-lowering agents and then redraw the labs.

I have already given him the Pneumovax to see if this will help clinicallyas well.

Finally, is there any specific contraindication in administering either IVIG or SCIG in patients with such high hyperlipidemia (Triglyceridemia)?

Thanks for any help that you can provide.

A:

Thank you for your inquiry.

It is true that hyperlipidemia can produce spurious measurements of immunoglobulins if they are measured by nephelometry. You did not mention the lab procedure used in measurement of immunoglobulins at the laboratory you used, but I assume this was the technique utilized.

For your interest, I have copied below three links to websites discussing the potential interference with the measurement of immunoglobulins performed by nephelometry by hyperlipidemia.

Unfortunately, I do not think we can quantitate the degree of interference, and therefore cannot be sure whether or not in your case it would be clinically significant. Nonetheless, I think your approach to the patient is reasonable, and my suspicion is, based on the levels of his immunoglobulins cited, and his lack of protective titers to pneumococcus serotypes, that he does indeed have hypogammaglobulinemia.

I could find no reference that hyperlipidemia would contraindicate replacement therapy with immunoglobulins either by the intravenous or subcutaneous route.I was not aware of any such contraindication, and could find none on an Internet search. In addition, I reviewed the package insert of two immunoglobulin preparations, and neither listed hyperlipidemia as a contraindication. However, if you do institute immunoglobulin replacement therapy, and are still in any way concerned about his hyperlipidemia being a contraindication, I would look at the package insert of the specific preparation you plan to use.

Thank you again for your inquiry and we hope this response is helpful to you.

Interferences in Immunoassay

Laboratory Investigation

Immunoglobulin Free Light Chains, Serum

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology