The associations of complete blood count with Th17 lymphocytes and C-reactive protein levels in overweight and obese children

Introduction
Obesity is considered as a risk factor for chronic low-grade systemic inflammation. This condition could be reflected in changes in complete blood count (CBC) and the presence of inflammatory markers. Assessment of CBC parameters and their correlation with Th17 cells and C-reactive protein (CRP) concentration in overweight/obese children in comparison to normal weight subjects.

Material and methods
Twenty-seven overweight/obese and 15 normal-weight children aged 8–18 years were enrolled in the study. The analysis included anthropometric measurements, CBC, biochemical, and immunological parameters. Th17 cells were identified by flow cytometry and defined as CD3+CD4+CD196+IL-17Aic+.

Results
In overweight and obese children there were significantly higher counts of leukocyte (p = 0.04), lymphocyte (p = 0.03), monocyte (p = 0.02), erythrocyte (p < 0.001), and haemoglobin concentration (p = 0.005). In the microscopic smear a lower eosinophil percentage was found in overweight/obese children compared to normal-weight children. Additionally, we detected significant relationships between anthropometric parameters and blood morphology elements, CRP, and Th17 cells in the group of all children, and a statistically significant positive correlation between Th17 frequency and erythrocyte value (p = 0.01, r = 0.38). Moreover, the band cell value in blood smear correlated with Th17 cells (p = 0.03, r = 0.34) and CRP concentration (p = 0.03, r = 0.33) in all children.

Conclusions
Obesity affects both white and red blood cell lineages. The finding of significant relationships between pro-inflammatory Th17 lymphocytes, CRP, and immature neutrophils as well as anthropometric markers of obesity may indicate that obesity-induced inflammation is be responsible for these alterations.