Topic:

Pediatric and perinatal infections

Abstract No.:

ISE.380

Title:

Relation of altered IgM, IgA or IgE levels to infectious diseases in hospitalized newborns of a third level hospital in Mexico city

Author(s):

S. Murrieta¹, V. Gomez-Toscano¹, J.-L. Hernandez-Islas¹, C. Lopez-Candiani², M. Macias-Parra³, H. Luna-Pastén¹, A. L. Castañeda-Huitrón¹, D. Correa¹; ¹Instituto Nacional de Pediatría, Lab. Inmunología Experimental, México, DF/MX, ²Instituto Nacional de Pediatría, Neonatología, México, DF/MX, ³Instituto Nacional de Pediatría, Infectología, México, DF/MX

Abstract:

Background: A Neonatal Screening Program has preventive-prophylactic purposes. In Mexico it is limited to diagnose only a small group of diseases, none of them infectious. In our country there are few data regarding frequency of subclinical congenital infection by screening-like procedures: three small studies allowed estimation of CMV (0.68%), toxoplasmosis (0.2%) and syphilis (0.15%). The screening is based on detection of specific immunoglobulins (Igs) that do not cross the placental barrier and hence are produced by the fetus, i.e. IgM (mainly) and IgA. Some studies have also shown that presence of IgE in the blood of newborns reflects exposition to allergens or parasites. Since it is costly to screen each infectious disease we decided to test the hypothesis that abnormally high levels of any of these Igs could be associated to infectiuos diseases acquired perinatally and thus to some clinical problems.
Methods: Ten neonates younger than 7 days who were hospitalized at the Neonatal Service of the National Institute of Pediatrics of Mexico were included. They presented variable clinical problems, unknown by the laboratory personnel who assessed the level of IgM, IgA and IgE in serum by antigen-capture ELISAs. Specific tests for infectious agents were performed to those presenting abnormally high levels of any of the Igs.  
Results: No baby presented abnormal levels of IgM, but one newborn had abnormal concentration of IgA (791 µg/mL) and another one extremely high levels of IgE (782 ng/mL). The first patient was cursing a severe Citomegalovirus infection (confirmed by positive CMV test) and the second had complicated cystic fibrosis. Seven babies presented non-infectious congenital disorders and one had early sepsis, without abnormal levels of any Ig. No co-infections were detected.
Conclusion: IgM, IgA or IgE abnormal levels can be associated with congenital or newborn infections, but not early sepsis. This high risk group was a good sample for pilot hypothesis regarding relation between abnormal levels of fetal Igs and infections.