Origin and Function of Eosinophilic Polynuclear During DRESS Syndrome

Inclusion Criteria: Group 1 (DRESS): adult with a diagnosis of DRESS based on the following four criteria:

• Cutaneous rash occurring at least 24 hours and at most 2 months after continuousmedication use
• Fever over 38 degre celcius
• At least one organ dysfunction among:
• Lymphadenopathy
• hepatitis
• Pulmonary involvement
• Cardiac involvement: myocarditis, pericarditis
• Renal impairment
• At least one of the following hematological anomalies:
• Eosinophilia ≥ 500 / mm3 .
• RegiSCAR Score ≥ 4 Groups 2 and 3 (Drug induced maculopapular exanthema without or with eosinophilia).
• Adult with drug-induced rash
• Without clinical criteria of severity defined by Djien among :
• An evolution of more than 21 days
• with organ damage as defined in group 1 Group 2 (MPE without eosinophilia): blood eosinophils < 500 / mm3 Group 3 (MPE with eosinophilia): blood eosinophils ≥ 500 / mm3

Exclusion Criteria:

• Other cause of eosinophilia including cancer, blood disease before the introduction ofsuspected molecule(s).
• On going oral or local corticosteroid therapy, anti-leukotriene therapy (MONTELUKAST)by the month preceding the study;
• Anti-IgE therapy (OMALIZUMAB, LIGELIZUMAB), anti-IL-5 therapy (MEPOLIZUMAB,BENRALIZUMAB) or anti-IL4 and / or anti-IL13 therapy (DUPILUMAB, TRALOKINUMAB) in the 6 months preceding the study.
• Any pregnant or lactating woman.
• Contraindication related to the blood volume taken for the study.