Lower Total Leukocyte and Neutrophil Counts in Healthy Young Africans from Uganda

The total leukocyte count (TLC) is an important component of the complete blood count and influences many clinical decisions. The effect of race or ethnicity on TLC is not well known. The African population has been reported to have lower than normal TLC and neutrophil counts. In this study, thirty eight African students referred for medical check up to a tertiary care hospital were included. Complete blood count was done on a three part automated hematology analyzer. Blood smear examination and manual differential count was also done. The control group included 38 age and sex matched healthy individuals. Student t test was used to compare the differences between the groups. The mean TLC in African students (4.95 ± 1.09 × 10⁹/l) was significantly lower (p < 0.0001) than that seen in the control group (7.42 ± 1.7 × 10⁹/l). The mean neutrophil percentage was also lower (49 ± 7.5%) in African students compared to the control group (63.6 ± 9.8%) [p < 0.0001] while lymphocyte percentage was higher (45.2 ± 7.5%) in the African students as compared to the control group (31.0 ± 9.3%) [p < 0.0001]. Absolute neutrophil count was also lower (2.45 ± 0.76 × 10⁹/l) in African students compared to the control group (4.76 ± 1.47 × 10⁹/l) while absolute lymphocyte count was comparable (2.21 ± 0.5 × 10⁹/l vs. 2.26 ± 0.72 × 10⁹/l) [p = 0.7212]. This study has shown lower leukocyte and neutrophil counts in apparently healthy African individuals. Knowledge of this variation from normal white cell and neutrophil counts is important in avoiding unnecessary investigations and influencing therapeutic decisions in these individuals.