[Venous thrombosis, unrecognized complication of DRESS]

DRESS (Drug Reaction with Eosinophilia and Systemic Symptoms) is a rare syndrome triggered by an immunological reaction to certain drugs and which may be life-threatening as a result of the onset of severe organ involvement. It is characterised by a long period from the time of drug therapy to the onset of actual signs. Herein, we report the case of 42-year-old female patient who developed DRESS one month after beginning allopurinol treatment.

A 42-year-old woman was hospitalised for febrile exanthema with facial oedema, polyadenopathy, mononucleosis syndrome, major hypereosinophilia and hepatic cytolysis. A diagnosis was made of DRESS with a RegiSCAR score of 5. The implicated drug was allopurinol, which had been initiated one month earlier. HHV-6 IgM serology was positive. Two days after the start of systemic corticosteroids, the patient developed thrombosis of the internal jugular vein. Other than major hypereosinophilia, no other factors favouring thrombosis were detected. A favourable outcome was achieved under effective anticoagulants and corticosteroids.

They have been rare reports of venous thrombosis during DRESS. Hypereosinophilia can be involved in the onset of this condition. Prophylaxis with systemic anticoagulants may be necessary in DRESS involving major hypereosinophilia.