Methods: Patients were enrolled if they received and were naïve to IVIG therapy. Blood was drawn prior to IVIG and 72-96 hours post-infusion. All samples were tested for: Bartonella, Coccidioides, Brucella, Histoplasma, Coxiella, West Nile, St. Louis, California, Eastern, and Western Encephalitis, Lyme, Dengue, HSV 1 and 2, Chikungunya, cytomegalovirus, varicella zoster, Epstein-Barr and Toxoplasma by standard methodologies (ARUP, Salt Lake City, UT). Pre- and post-infusion antibody concentrations were evaluated to determine the potential false-positive rate of serologic testing.
Results: Seven patients received IVIG (renal transplant rejection, 2 patients; Guillain-Barre syndrome, 3 pts; bone marrow transplant, 2 pts). Six of seven patients receiving IVIG had at least one evaluated serology become positive 72 hours after IVIG infusion. Antibodies for CMV, HSV-2, and EBV early antigen D turned positive in 3 patients. Antibodies for WNV, Coccidioides IgG, and Histoplasma yeast IgG became positive in 2 patients. Lastly, antibodies for HSV-1 and 2, and EBV nuclear antigen each turned positive in 1 patient.
Patients received between 20-112.5 grams. Of the 3 patients who received more than 100g of IVIG, 2 had at least 4 serologies turn positive. Of the patients who received less than 100g (20 – 50g), none had more than 3 turn positive (p <0.05). One patient had 3 serologies turn negative (Coccidioides, HSV 2, and EBV Early D) after infusion of 36.5g of IVIG, with none turning positive.
Conclusion: Use of IVIG has increased significantly over the past decade, however the potential pitfalls in serologic diagnostics associated with receipt of IVIG have not been studied systematically and is likely a confounder in serologic diagnostics causing both false-positive and false-negative results. We found a number of screening and diagnostic serologies can be artificially altered after infusion of IVIG.
K. E. Hanson,
I. Mchardy, None
W. Hoffmann, None
S. H. Cohen, None
R. Welch, None
M. R. Couturier, None
G. R. Thompson, None