Background: The immune status of children exposed prenatally to immunosuppressants is not fully understood.
Material and methods: A single-center study evaluated possible differences in antibody levels between children prenatally exposed to immunosuppressants born to mothers after hepatic or kidney transplantation (study group) compared to children without prenatal exposure to immunosuppressants (control group). Children from the study and control group were age-matched at the time of the examination and gestational age-matched, so as to obtain similar stages of the vaccination schedule and to enable reliable comparison of the results. The selection of children was made in a 1:1 ratio. The study population, a total of 138 children, was divided according to the age of the children at the time of the study into three age groups: newborns, infants (from 29 days to 1 year) and children aged >1 year. Immunoenzymatic tests were used to analyze the titers of the chickenpox virus (VZV-IgG), rubella (RuV-IgG) and hepatitis B virus (HBV, HBsAb). The studied differences were compared depending on the age group and the immunosuppressive regimen used by the pregnant mother.
Results: In neonates born to mothers after liver transplantation, significant differences were found in HBsAb levels (>250 mIU/ml) compared to newborns without prenatal exposure to immunosuppressants taken by pregnant mothers (11/16, 69% vs. 4/14, 29%, respectively; p = .028). A similar difference in the level of HbsAb was no longer noted at later stages of children's lives. In infants, these values were 80% (4/5) vs. 33% (2/6), and in children over 1 year of age 15% (7/48) vs. 12% (6/49), respectively. No other significant differences were noted when compared the distribution of measured parameters of VZV and RuV in both analyzed groups (children of mothers after kidney or liver transplantation chronically treated with immunosuppression and children without prenatal exposure to immunosuppression).
Conclusions: Prenatal exposure to immunosuppressive therapy does not appear to affect VZV, RuV and HBV antibody levels in children of mothers who have had a kidney or liver transplant. Initially elevated HBSAb levels in newborns of mothers after liver transplantation are not observed in later stages of life.
Keywords: Kidney transplantation; antibody levels; children of transplanted mothers; immunosuppressive therapy; liver transplantation; prenatal exposure.