TY - CHAP M1 - Book, Section TI - Pernio A1 - Zafren, Ken A1 - Thurman, R. Jason A1 - Jones, Ian D. A2 - Knoop, Kevin J. A2 - Stack, Lawrence B. A2 - Storrow, Alan B. A2 - Thurman, R. Jason Y1 - 2021 N1 - T2 - The Atlas of Emergency Medicine, 5e AB - Pernio, also known as perniosis or chilblains, is the result of nonfreezing cold exposure in susceptible individuals. Pernio appears within 24 hours of cold exposure, most frequently on the face, ears, hands, feet, and pretibial areas. A large range of lesions may be seen, with localized edema, erythema, cyanosis, plaques, and blue nodules occasionally progressing to more severe lesions including vesicles, bullae, and ulcerations. The lesions persist for up to 2 weeks and may become chronic. They are typically very pruritic and associated with burning paresthesias. Following rewarming, pernio often takes the form of blue nodules, which are quite tender. In the setting of recent cold exposure, pernio might be confused with the more severe syndrome of trench foot. If the history of cold exposure is not elicited, the differential diagnosis is potentially very broad. SN - PB - McGraw-Hill CY - New York, NY Y2 - 2024/10/06 UR - accessemergencymedicine.mhmedical.com/content.aspx?aid=1181050836 ER -