Abstract: Objective To investigate eosinophil percentage（EOS%），serum CC chemokine receptor 3（CCR3） and eotaxin of children with acute bronchopneumonia and their relationship with disease severity. Methods A total of 126 children with acute bronchopneumonia（bronchopneumonia group） were enrolled. According to the clinical pulmonary infection score（CPIS）of children with acute bronchopneumonia on admission，they were classified into mild group（81 cases，CPIS≤6）and severe group（45 cases，CPIS>6）. Totally，60 healthy children were enrolled as healthy control group. The EOS% and serum CCR3 and eotaxin levels of all the subjects were determined，the lung function indicators [tidal volume（VT），respiratory rate（RR），the ratio of volume to peak expiratory flow to total expiratory volume（VPTEF/VE）and the ratio of time to peak tidal expiratory flow to total expiratory time（TPTEF/TE）] of children with acute bronchopneumonia were determined. Pearson correlation analysis was used to evaluate the correlation between various indicators，and receiver operating characteristic（ROC） curve was used to evaluate the diagnostic values of EOS%，serum CCR3 and eotaxin levels in children with severe acute bronchopneumonia. Results The levels of EOS%，serum CCR3 and eotaxin in bronchopneumonia group were higher than those in healthy control group（P=0.000）. Compared with mild group，the levels of serum CCR3，eotaxin，EOS% and RR in severe group were higher（P<0.01），and VT，VPTEF/VE，TPTEF/TE were lower（P<0.01）. The levels of EOS%，serum CCR3 and eotaxin in children with acute bronchopneumonia were positively correlated with RR（P<0.05），and they were negatively correlated with VPTEF/VE and TPTEF/TE（P<0.05），but without VT（P>0.05）. ROC curve analysis results showed that the areas under curves（AUC）of single determinations and combined determination of EOS%，serum CCR3 and eotaxin levels for the diagnosis of severe acute bronchopneumonia were 0.861，0.762，0.826 and 0.931，respectively. Conclusions Serum CCR3，eotaxin and EOS% are related to the severity of acute bronchopneumonia in children，and they can reflect the status of lung function to a certain extent，or they can be used as serological indicators for clinical judgment of the development of acute bronchopneumonia.

Key words: Eosinophil percentage, CC chemokine receptor 3, Eotaxin, Acute bronchopneumonia in children