Cytochemical leukocyte reactions in normal children.

Five cytochemical reactions in current use (MPO, PAS, LAP, SB and EST) were operated on 180 children aged 1 month to 6 years, divided into three age groups (less than 12 months, 1-3 years and 3-6 years). No significant differences are apparent from one group to another, and the mean values are identical with those of adults. On the other hand, certain variations are evident in comparison with the scores of newborn children: important decrease in LAP, increase in SB, EST and PAS. These tests should be done in investigations of inborn metabolic errors, chromosome anomalies, blood diseases, and defects in defense mechanisms.