The Algorithmic Approach to the Unidentified Rash

  • Heather Murphy-Lavoie
  • Tracy LeGros


Dermatologic conditions are usually nonemergent but occasionally represent a life-threatening condition. This chapter presents an algorithmic approach to the ED patient with a rash. A set of four algorithms are presented dividing rashes into diffuse erythema, maculopapular, vesiculobullous, and petechial or purpuric. For each category, the key distinguishing features are included that help differentiate the common from life-threatening conditions.


Dermatologic Rash Erythema Maculopapular Vesiculobullous Petechiae Purpura Nikolsky Fever Distribution Vasculitis Thrombocytopenia 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Heather Murphy-Lavoie
    • 1
  • Tracy LeGros
    • 1
  1. 1.Louisiana State University School of MedicineEmergency Medicine ResidencyNew OrleansUSA

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