Immunological patterns in young children with Down syndrome: is there a temporal trend?

Down syndrome is associated with an increased susceptibility to infections due to a deficiency of both specific and nonspecific immunity. Aim: The aim of the study was to analyze the temporal trends, if any, of some variables related to the immunological status of children affected by Down syndrome. Methods: Heparinized blood samples were obtained by venipuncture in 30 children with Down syndrome, who were regularly followed in our department and analyzed for hematologic values, lymphocyte subpopulations, immunoglobulin dosage and zinc level. Results were compared with those of the normal population. Results: In the first 5 years of life, we observed a progressive decrease in the medium values of lymphocytes, CD4(+) and plasma zinc levels, and an increase in CD8(+), immunoglobulin A, immunoglobulin G, immunoglobulin M and natural killer, but generally without exceeding the interval of normality. Conclusions: In Down syndrome children, the immune cellular status is similar to the normal population as far as white blood cell, lymphocyte, CD4(+), CD8(+), natural killer and immunoglobulins are concerned. Plasma level of zinc is normal from birth until 5 years but with a temporal trend of progressive reduction. This observation supports the hypothesis that a pharmacological supplementation may be necessary in Down syndrome children only after 5 years of age.