Severe drug-induced skin reactions: clinical features, diagnosis, etiology, and therapy.

Drugs can induce severe skin reactions that differ in clinical presentation, prognosis, and therapy. The spectrum of these reactions not only includes bullous reactions such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and generalized bullous fixed drug eruption (GBFDE) but also acute generalized exanthematous pustulosis (AGEP) and drug reaction with eosinophilia and systemic symptoms (DRESS). If AGEP or DRESS is suspected, the diagnosis should be confirmed by thorough clinical examination, a skin biopsy, and specific laboratory tests. Crucial for the patient's prognosis, the causative agent should be rapidly identified and discontinued. It is therefore important to know the most frequent triggers of severe drug reactions, some of which may induce various reaction patterns. Depending on the clinical diagnosis, symptomatic and adequate supportive therapy, as well as systemic immunomodulatory treatments are used. The prognosis in SJS/TEN is often poor and depends on the patient's age and underlying conditions as well as the extent of skin detachment. The prognosis of GBFDE is somewhat better, but recurrences may lead to more severe disease manifestations. In DRESS, protracted and recurrent courses have been described, whereas AGEP usually resolves without problems.