LAUSR

Importance Cases of photodistributed Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) have been infrequently reported since the first documented case in 1989. This emerging clinical entity and its underlying mechanism have yet to be fully characterized. Objective To report a case of photodistributed SJS/TEN and highlight similarities to other cases reported in the literature. Design, Setting, and Participants Case report and literature review of published cases of photodistributed SJS/TEN. The case report describes a 29-year-old woman with recent lamotrigine and trimethoprim-sulfamethoxazole exposure who developed TEN in a photodistributed pattern 1 day after prolonged sun exposure. A search of PubMed using the keywords toxic epidermal necrolysis, Stevens-Johnson syndrome, photo-distributed, photo-induced, and sun-exposed was performed to identify other cases reported in the literature. Results Literature review revealed 8 previously reported cases of healthy individuals with known drug and UV radiation (UVR) exposures who subsequently developed SJS or TEN with photodistribution. Cases reviewed were skewed demographically to young women aged 19 to 48 years (8 of 9 patients) with all cases reporting UVR exposure 24 to 72 hours prior to the onset of symptoms. Conclusions and Relevance Photodistributed TEN has been increasingly described in the literature and may represent a distinct variant of SJS/TEN. While the pathogenesis remains unclear, the role of UVR as a "second hit" is suggested by the data presented in the cases documented thus far.