The balance between the serum levels of IL-6 and IL-10 cytokines discriminates mild and severe acute pneumonia

Abstract

Background: To identify markers for earlier diagnosis of severe pneumonia, we assess the correlation between serum cytokine profile of children with different pneumonia severity.

Methods: In 25 hospitalized children, 7 with mild pneumonia and 18 with severe pneumonia, the serum concentration of 11 cytokines in three sampling times were dosed. Statistical analysis included parametric and non-parametric tests, Pearson correlation and ROC curve for cut-off definition of cytokines.

Results: At admission, IL-6 serum levels were high in mild or severe pneumonia, and was associated to vomiting (P = 0.019) in both groups; and also to dyspnea (P = 0.012) and white blood cell count (P = 0.045) in patients with severe pneumonia. IL-10 levels were also high in patients with pneumonia and were associated to lymphocytosis (P = 0.025). The ROC curve of the IL-6:IL-10 serum levels ratio discriminated severe pneumonia cases at admission, and persistence of infection in the third day of antibiotic therapy, with positive predictive values of 93% and 89%, respectively.

Conclusions: The balance between IL-6 and IL-10 serum levels showed to be a more discriminative marker for severity definition and evaluation of recovery in patients with pneumonia.

Keywords: Cytokines; Immune response; Inflammation; Pneumonia.

Fig. 1

Balance between IL-6 and IL-10 during recovery from pneumonia of different severity. Seric levels of IL-6 (left) and IL-10 (middle) cytokines, and the ratio of seric levels of IL-6:IL-10 (right) in group of children diagnosed with non-severe pneumonia (top) or severe pneumonia (bottom). IL-6 levels, in non-severe pneumonia, at admission x D8 (P = 0.025); IL-6 levels, in severe pneumonia, at admission x D3 (P = 0.003) and at admission x D8 (P = 0.003); Ratio IL-6:IL-10, in non-severe pneumonia, at admission and D3 (P = 0.025) and D3 x D8 (P = 0.025); Ratio IL-6:IL-10, in severe pneumonia, at admission x D3 (P = 0.005); at admission and D8 (P = 0.005) and D3 x D8 (P = 0.034)