Objective  To identify the clinical features of eosinophilia caused by parasitic infection.

  Methods  We reviewed and analyzed the clinical characteristics, peripheral eosinophils count, species of parasites, and system involvement of 87 patients with parasitic infections who were diagnosed and admitted in Peking Union Medical College Hospital (PUMCH) between January 2010 and December 2014.

  Results  Of the 87 patients with parasitic infections, increased count of peripheral eosinophils occurred in 33.3% (29/87) patients, and hypereosinophilia with eosinophil count over 1.5×10⁹/L in 14.9% (13/87) patients. Paragonimus westermani (100%), Schistosoma (83.3%), and Clonorchis sinensis (57.1%) were the three most common parasites leading to eosinophilia. The infected patients with pulmonary and digestive system involvement were more likely to develop eosinophilia, with the proportion of patients having eosinophilia being 85.7% and 50.0%, respectively, and the proportion of patients having hypereosinophilia being 28.6% and 33.3%, respectively.

  Conclusions  The percentage ofpatients having eosinophilia among those with parasitic infections may vary with the species of parasites and involved organ. The differential diagnosis in hypereosinophilia should consider the possibility of parasitic infection.