REFERENCE RANGES FOR LYMPHOCYTE SUBSETS IN PEDIATRIC-PATIENTS

Peripheral blood lymphocyte subset reference ranges were examined in a large group (N = 130) of healthy pediatric patients ranging in age fr om 1 month to 17 years. All samples were stained with monoclonal antib odies, processed with a whole blood lysis technique, and analyzed on a flow cytometer. Dats analysis demonstrated statistically significant changes in most lymphocyte subsets at age 3 years. The relative and ab solute numbers of total lymphocytes, CD2, CD4, and CD19 cells; absolut e numbers of CD3 and CD8 cells; and CD4/CD8 ratios were high at birth, decreased during early childhood, and closely approximated adult refe rence values after age 3 years. The relative numbers of CD8 lymphocyte s were low in early childhood and then rose to adult values after 3 ye ars of age. The relative percentage of CD3 cells remained stable over all ages studied. Although ''adult'' lymphocyte subset reference range s may be similar to those in children older than 3 years, age-adjusted reference ranges should be used for the early childhood period.