Elsevier

The Journal of Pediatrics

Volume 147, Issue 6, December 2005, Pages 744-747
The Journal of Pediatrics

Original Article
Intrinsic Abnormalities of Lymphocyte Counts in Children with Down Syndrome

https://doi.org/10.1016/j.jpeds.2005.07.022Get rights and content

Objective

Down syndrome (DS) is associated with an increased frequency of infections, hematologic malignancies, and autoimmune diseases, suggesting that immunodeficiency is an integral part of DS that contributes significantly to the observed increased morbidity and mortality. We determined the absolute counts of the main lymphocyte populations in a large group of DS children to gain further insight into this immunodeficiency.

Study design

In a large group of children with DS (n = 96), the absolute numbers of the main lymphocyte subpopulations were determined with 3-color immunophenotyping using the lysed whole-blood method. The results were compared with previously published data in healthy children without DS.

Results

In healthy children with DS, the primary expansion of T and B lymphocytes seen in healthy children without DS in the first years of life was severely abrogated. The T- lymphocyte subpopulation counts gradually reached more normal levels with time, whereas the B- lymphocyte population remained severely decreased, with 88% of values falling below the 10th percentile and 61% below the 5th percentile of normal.

Conclusions

The diminished expansion of T and B lymphocytes strongly suggests that a disturbance in the adaptive immune system is intrinsically present in DS and is not a reflection of precocious aging. Thymic alterations have been described in DS that could explain the decreased numbers of T lymphocytes, but not the striking B lymphocytopenia, seen in these children.

Section snippets

Study Population

The study was performed with the informed consent of the patient's parents according to the guidelines of the medical ethics committees of Jeroen Bosch Hospital, ‘s-Hertogenbosch and Rijnstate Hospital, Arnhem. The study group comprised 96 noninstitutionalized children with DS, 50 males and 46 females, ranging in age from 1 to 20 years (mean age, 7 years). During routine follow-up of thyroid function, a small volume of EDTA blood (4 mL) was drawn for the study. All children were healthy at the

Results

The median and ranges of the absolute counts of the main lymphocyte subpopulations in 96 children with DS are listed in the Table. The median absolute counts of lymphocyte subpopulations compared with the median absolute counts of healthy children without DS15 are shown in Figure 1. The absolute counts of total lymphocytes, T and B lymphocytes, and NK cells of each child with DS in relation to the 5th, 10th, 90th, and 95th percentiles of normal15 are shown in Figure 2. No significant

Discussion

During the first years of life, massive activation, proliferation, and maturation of T and B lymphocytes occur in response to continuous encounters with antigens from the environment. In the children with DS, this early expansion of T and B lymphocytes was severely abrogated, irrespective of the frequency of infections or development of autoimmunity. This strongly suggests that a disturbance of the adaptive immune system is in fact intrinsically present in DS and is not acquired later as a

References (22)

  • E.J. Glasson et al.

    The changing survival profile of people with Down's syndrome: implications for genetic counseling

    Clin Genet

    (2002)
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    Supported by the foundations “Het Wetenschapsfonds,” Je-roen Bosch Hospital, and “Het Irene Kinderziekenhuis.”

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