Epidermal necrosis

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Confluent epidermal necrosis. H&E stain.

Epidermal necrosis is an important finding in dermatopathology. Full-thickness necrosis, especially is very serious.

General

Full thickness DDx:

  • Erythema multiform (EM).
  • Toxic epidermal necrolysis (TEN).
  • Stevens-Johnson syndrome (SJS).
  • Trauma.
  • Others. (???)

Partial thickness DDx:

  • Staphylococcal scalded skin syndrome.
  • Trauma. (???)
  • Others. (???)

Notes:

  • SJS and TEN are on a spectrum, EM (depending on who you ask) is considered separate.
    • These are signed-out as "confluent epidermal necrosis - see comment".
      • Comment: The histomorphologic findings are consistent with EM/SJS/TEN.
    • The clinical DDx of EM/SJS/TEN includes acute generalized exanthematous pustulosis (AGEP).

Erythema multiforme

  • Abbreviated EM.

General

Features:[1]

Clinical:

  • Target-like lesion.

Microscopic

Features:[1]

  • Lymphocytic interface dermatitis (lymphocytes at the dermal-epidermal junction).
  • Necrotic/degenerative keratinocytes - key feature.
  • +/-Epidermal blistering.
  • +/-Epidermal sloughing.

Images

Stevens-Johnson syndrome

  • Abbreviated SJS.

General

Rx causes of SJS:

  • NSAIDs.
  • Anticonvulsants.
  • Sulfonamides.
  • Penicillins.

Microscopic

Features:

Images

Toxic epidermal necrolysis

  • Abbreviated TEN.

General

  • TEN more severe form SJS.

Definition:

  • >30% sheet-like epidermal detachment, diffuse erythema, severe mucous membrane involvement.
  • Most TEN (80%) Rx-related, only 50% of SJS Rx-related.

Microscopic

Features:

Images

Staphylococcal scalded skin syndrome

  • Abbreviated SSSS.

General

  • Due to keratinocyte cell-cell adhesion loss in the superficial epidermis - caused by S. aureus.[3]

Clinical:

  • Blisters

Microscopic

Features:[3]

  • Superficial dermis separates from underlying tissue - looks artefactual.
  • Minimal/scant inflammation is typical.[4]

Image:

See also

References

  1. 1.0 1.1 Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1189. ISBN 978-1416031215.
  2. S. Sade. 8 September 2011.
  3. 3.0 3.1 Nishifuji, K.; Sugai, M.; Amagai, M. (Jan 2008). "Staphylococcal exfoliative toxins: "molecular scissors" of bacteria that attack the cutaneous defense barrier in mammals.". J Dermatol Sci 49 (1): 21-31. doi:10.1016/j.jdermsci.2007.05.007. PMID 17582744.
  4. URL: http://dermatlas.med.jhmi.edu/derm/display.cfm?ImageID=2105774586. Accessed on: 22 September 2011.