Link Between Eosinopenia and Bacterial Infections in the Elderly Subject Hospitalized in Geriatrics

Inclusion Criteria: * Hospitalized in Geriatrics. * First episode of: * Fever\> 38 ° motivating the realization of a biological assessment. * Or Leukocytes\> 10 g / l and C reactive protein (CRP) \> 20 mg / l. * Be affiliated to a social security scheme. * No oral opposition to participation in the study and use of the data. Exclusion Criteria: * Immunosuppression (HIV with CD4 \<200 / mm3) * Active corticosteroid therapy * Asthma * Chemotherapy, immunosuppressive treatment * Malignant hematological disease, lympho or myeloproliferative syndrome * Antibiotic therapy initiated before entering the geriatric ward * Documented parasitosis * Eosinophilic vasculitis * stroke \<30 days * Patient already included in another study * Patient under guardianship or curatorship * Not affiliated with a social security scheme * Oral opposition to participation in the study