Purpura

Background

  • Palpable petechiae and purpura are a result of either perivascular inflammation (vasculitis) or infection.
  • Non-palpable petechiae usually occur in low platelet states such as ITP and DIC

Rash Red Flags[1]

Clinical Features

Both petechia and purpura do not blanch

  • Purpura subdivided into:
    • <2mm of hemorrhage: petechiae
    • >2mm of hemorrhage: ecchymoses

Purpural Rash

Differential Diagnosis

Petechiae/Purpura (by cause)

Petechiae/Purpura (by findings)

Evaluation

  • For children with fever and petechiae/purpura consider using the Barts Health NHS Trust guideline for workup. This guideline performed well head to head vs other guidelines in Petechiae in Children (PiC) study. [2] [3]
Fever and non-blanching rash in children algorithm from Barts Health NHS Trust guideline. Original image from https://dontforgetthebubbles.com/petechiae-in-children-study/

Management

  • Management directed by underlying condition

Disposition

  • Depends on underlying etiology

See Also

References

  1. Nguyen T and Freedman J. Dermatologic Emergencies: Diagnosing and Managing Life-Threatening Rashes. Emergency Medicine Practice. September 2002 volume 4 no 9.
  2. Thomas et, al. Validating clinical practice guidelines for the management of children with non-blanching rashes in the UK (PiC): a prospective, multicentre cohort study, The Lancet Infectious Diseases, 2020, https://doi.org/10.1016/S1473-3099(20)30474-6
  3. Tessa Davis. Petechiae in Children – the PiC Study, Don't Forget the Bubbles, 2020. Available at: https://doi.org/10.31440/DFTB.30782