Periorbital necrotizing sweet syndrome: A report of two cases mimicking necrotizing soft tissue infections.

Purpose: Two cases are described of necrotizing Sweet syndrome (nSS), a rare variant of acute febrile neutrophilic dermatosis that mimics necrotizing soft tissue infections. Observation: A 74-year-old female with myelodysplastic syndrome (MDS) presented with isolated periorbital nSS that closely mimicked necrotizing fasciitis (NF); she displayed pathergy to debridement, was exquisitely responsive to corticosteroids, and underwent successful first-stage reconstruction of the eyelid with full-thickness skin grafting. A second 40-year-old female patient with relapsed acute myelogenous leukemia (AML) presented with multifocal nSS most prominently involving the eyelid. Positive herpes zoster virus (HSV) PCR and bacterial superinfection complicated the diagnosis. She improved with chemotherapy for AML and corticosteroid therapy. Conclusion: nSS is rare and a high level of clinical suspicion as well as an understanding of its distinguishing features is necessary to avoid undue morbidity. Identification of pathergy, histopathology, microbiology, and clinical context are critical to avoid misdiagnosis of infection.