Sweet syndrome (SS), or acute febrile neutrophilic dermatosis, is a hypersensitivity reaction associated with hematologic and solid malignant conditions, infection, inflammation, and, less commonly, medications. Two reports have implicated trimethoprim sulfamethoxazole (TS) in the onset of SS.1,2 Mechanistic hypotheses for drug-induced SS cite the contribution of cytokines3 or a hypersensitivity reaction.4 In cases related to granulocyte colony–stimulating factor (G-CSF) and all-trans retinoic acid (ATRA), a mechanism involving neutrophil stimulation is suggested.4 In a report of TS-induced SS, Walker and Cohen2 suggest diagnostic criteria for drug-induced SS (Table). We describe a case of TS-induced SS meeting these criteria.
Azfar RS, Cohn J, Schaffer A, Kim EJ. Trimethoprim Sulfamethoxazole–Induced Sweet Syndrome. Arch Dermatol. 2009;145(2):215-216. doi:10.1001/archderm.145.2.215