Bullous fixed drug eruption masquerading as recurrent Stevens Johnson syndrome.

BACKGROUND: Fixed drug eruptions (FDE) are peculiar drug rashes that tend to be violaceous, hyperpigmented, and round to oval-shaped plaques with dusky gray centers. The lesions tend to recur in a similar dermatologic distribution upon re-exposure to the offending medication, leading to intensified inflammation and sometimes the formation of blisters, bullae, and erosions. This bullous form of FDE can be mistaken clinically for Stevens Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN).

CASE REPORT: We report two cases of patients presenting to the emergency department (ED) with characteristic blistering skin lesions and reports of similar prior episodes; both patients were initially diagnosed in the ED as "recurrent SJS" and admitted to the burn intensive care unit. Each patient was evaluated emergently by dermatology consultants, identified as cases of FDE rather than SJS, and transferred to the general medical ward with an uncomplicated hospital course and complete re-epithelialization within 7 days after removal of the inciting agent. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: We discuss distinguishing features of bullous FDE and SJS/TEN in order to highlight this entity and aid in diagnostic accuracy and appropriate management by emergency physicians. In cases identified as classic or suspected SJS/TEN, the patient warrants aggressive resuscitation and admission to a burn unit, while cases identified as obvious bullous FDE can be managed much more conservatively. Although the clinical clues outlined here may help distinguish classic cases of FDE from SJS/TEN, it is always advisable to admit to a higher level of care or obtain an urgent dermatology consult when diagnostic uncertainty remains.