The causative drugs and the prevalence of severe bullous hypersensitivity reactions

Background According to recent studies about 1-3% of hypersensitivity reactions are accompanied by skin eruptions. Among these toxic epidermal necrolysis (TEN) and StevensJohnson syndrome (SJS) are rare and the most severe adverse cutaneous drug reactions that predominantly involve the skin and mucous membranes. TEN and SJS affecting approximately 1-4/1,000,000 annually with average reported mortality rate 25-35% (TEN), and 1-5% (SJS). The aim of this work was to study the frequency of severe bullous delayed allergic reactions, like TEN and SJS, their clinical presentations, causative drugs, treatment and the diagnostic approach required.