title: Total and differential leucocyte counts in infants at 2, 5 and 13 months of age.
abstract: Reference ranges for the total and differential leucocyte counts were determined from venous blood collected at 2, 5 and 13 months of age from a cohort of 112 healthy children of north European ancestry. At 2, 5 and 13 months, the ranges for neutrophils were found to be 0.7-4.7, 1.1-5.6 and 1.0-7.6 x 109/l, and for lymphocytes 3.3-10.5, 3.4-11.3 and 3.5-10.4 x 109/l, respectively. The upper limits for monocytes at each age were 1.2, 1.2 and 0.91 x 109/l, and for eosinophils 0.84, 1.0 and 0.88 x 109/l, respectively. Mean counts for all cell types, except monocytes, increased between 2 and 5 months of age. There was little change in mean counts between 5 and 13 months. Statistically significant correlations existed between the numbers of each cell type at 2 months of age, and were still present at 13 months between monocytes and each of the granulocyte series and between basophils and all other cell types. By comparison with older data these findings indicate a lower reference limit for neutrophils at 2 months of age, and a narrower range for this cell type at both 2 and 5 months of age. Reference ranges for lymphocytes and eosinophils are wider than indicated by some previous studies.
authors.affiliation: Sub-department of Paediatric Haematology and Division of Child Health, The University of Sheffield, The Sheffield Children's Hospital NHS Trust, Western Bank, Sheffield, UK.
authors.forename: G J
authors.initials: GJ
authors.lastname: Bellamy
authors.forename: R F
authors.initials: RF
authors.lastname: Hinchliffe
authors.forename: K C
authors.initials: KC
authors.lastname: Crawshaw
authors.forename: A
authors.initials: A
authors.lastname: Finn
authors.forename: F
authors.initials: F
authors.lastname: Bell
mesh_terms: D015331:Cohort Studies; D003627:Data Interpretation, Statistical; D005060:Europe / Q000208:ethnology; D006801:Humans; D007223:Infant; D007958:Leukocyte Count; D009000:Monocytes / Q000166:cytology; D009504:Neutrophils / Q000166:cytology; D016011:Normal Distribution; D012016:Reference Values; D012737:Sex Factors; D014680:Veins