Eosinophilia during Hantavirus infection: a cohort study

There are emerging eosinophil-related considerations concerning viral infections. The role of eosinophils has poorly been evaluated during Hantavirus infection.The aim of this study was to determine the prevalence of eosinophilia (defined as an eosinophil count above 500 cells/mm3) during haemorrhagic fever with renal syndrome (HFRS) in a large cohort of patients, and to identify factors associated with eosinophilia.Among 387 patients hospitalized for HFRS, 98 (25.3%) had eosinophilia. By univariate analysis, eosinophilia was significantly associated with more severe thrombocytopenia, high C-reactive protein level, white blood cell count and neutrophil count and lower nephrotoxic drug intake. As there was a collinearity between white blood cell count and C-reactive protein level, only C-reactive protein level with platelet count and nephrotoxic drug intake were entered in the multivariable analysis. Elevated C-reactive protein concentrations remained independently associated with eosinophilia.Eosinophilia during HFRS affects one quarter of patients, and supports the role of eosinophils in antiviral immunity against hantavirus infection.