Immune Response of Patients With Chronic, Staphylococcus Aureus-infected Wounds

Inclusion Criteria: * The patient must have given his/her informed and signed consent * The patient must be insured or beneficiary of a health insurance plan * The patient is available for 6 months of follow up * Patients consulting at the departments of Diabetology, Dermatology or Infectious Diseases of the participating hospitals * inaugural or recurrent diabetic foot/ankle ulcers of Grade 2-4, or (2) who have an infected leg ulcer (arterial, venous, or mixed. Controls: * Absence of bacteriemia Cases: * Presence of bacteriemia Exclusion Criteria: * The patient is participating in another study * The patient is in an exclusion period determined by a previous study * The patient is under judicial protection, under tutorship or curatorship * The patient refuses to sign the consent * It is impossible to correctly inform the patient * The patient is pregnant, parturient, or breastfeeding * The patient does not have a chronic wound * Patient with grand 1 ulcer * Patient's wound/ulcer is not infected * Patient's would/ulcer is infected, but not involving S. aureus