Bullous lesions in a patient with systemic lupus erythematosus.

Bullous eruptions in patients with lupus erythematosus can be difficult to diagnose as bullous lesions can develop in lupus-specific lesions, and primary blistering disorders can also occur. Additionally, these patients tend to have multiple co-morbidities making them more likely to be on many medications that can lead to bullous drug reactions. A thorough history, the clinical presentation, and histopathological findings along with direct immunofluorescence can be helpful in diagnosing most cases. The authors report the case of a woman with a long history of systemic lupus erythematosus who initially presented in their clinic for diagnosis and management of erythema dyschromicum perstans and one year later developed bullae in atypical targetoid lesions on the extremities and trunk. They discuss several blistering disorders that have been reported in patients with lupus erythematosus with a focus on features that help distinguish erythema multiforme, fixed drug eruption, and lupus erythematosus from Stevens-Johnson syndrome/toxic epidermal necrolysis. In the patient described herein, the authors favor a diagnosis of Stevens-Johnson syndrome, but the classification between erythema multiforme major and Stevens-Johnson syndrome/toxic epidermal necrolysis cannot be made in some cases.