Necrosis

Necrosis is a type of cell death that is characterized by inflammation.

It is always pathologic. The differential diagnosis of necrosis is very broad; it is important to not be focused only on cancer and infections.

Classic types

As per Robbins:^[1]

Coagulative.
Liquefactive.
Gangreneous.
Caseous.
Fatty necrosis.
Fibrinoid.

Coagulative

Features:^[2]

General: most common; proteinlysis > autolysis/heterolysis.
Where/when: all tissue except the brain.
Microscopic: cell outlines present.

Liquefactive

Features:^[2]

General: proteinlysis < autolysis/heterolysis.
Where/when: infections, brain, abscess.
Microscopic: nothing left; pink on H&E.

Other classic types

Gangrenous: coagulative necrosis in ischemic limb.
Caseous: chessy material; tuberculosis.
Fat: adipose tissue, e.g. pancreatitis.
Fibrinoid: immune complex mediated; bright-pink in vessel walls.

Other types

Gross

Coagulative necrosis:

Soft.
Grey or white.

Liquefactive necrosis:

Mushy, grey.
Porridge-like consistency.

Image:

Liquefactive necrosis (utah.edu).

Microscopic

Features:^[3]

Dead cells - (too much pink on H&E) - one of the following:
1. Anucleate cells ("Ghost cells") - outlines of cells only.
  - Usually subtle.
  - Fluffy appearance.
2. Karyolysis - nucleus disintegrating.
3. Karyorrhexis - nucleus fragmenting.
4. Pyknosis - nuclear strinkage.
  - Weak sign.
Inflammation - typically neutrophils (very common).

DDx of necrosis:

Fibrin.

Notes:

Inflammation is a reactive phenomenon; it requires blood flow.
- Post-mortem it is not found.

Images

Necrosis in cat scratch disease. (WC/Nephron)
Necrosis in histiocytic necrotizing lymphadenitis. (WC/Nephron)
Necrosis in SLE lymphadenopathy. (WC/Nephron)
Fat necrosis - high mag. (WC/Nephron)
Necrotic bone. (WC/Nephron)
Radiation necrosis in the CNS. (WC/Tdvorak)

www:

Stains

Martius scarlet blue stain - fibroid necrosis = red.

Sign out

LESION, ANTERIOR RECTUS WALL, SURGICAL BIOPSY:
- EXTENSIVE FAT NECROSIS.
- NO EVIDENCE OF MALIGNANCY.

Micro

The sections show fibroadipose tissue with abundant foamy histiocytes and necrotic adipocytes. Scattered chronic inflammatory cells, including plasma cells eosinophils and lymphocytes, are present. Focally hemosiderin-laden macrophages are identified. Multi-nucleated giant cells are seen. No definite epithelium is identified. Some reactive fibroblasts are present. No significant nuclear atypia is identified.

References

↑ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 21-22. ISBN 0-7216-0187-1.
↑ ^2.0 ^2.1 Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 6. ISBN 978-1416054542.
↑ Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 4. ISBN 978-1416054542.
↑ URL: http://moon.ouhsc.edu/kfung/jty1/Com08/Com801-1-Diss.htm. Accessed on: 3 November 2010.

[Ref_PBoD21-22-1] Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 21-22. ISBN 0-7216-0187-1.

[Ref_PCPBoD8_6-2] 2.0 ^2.1 Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 6. ISBN 978-1416054542.

[Ref_PCPBoD8_4-3] Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 4. ISBN 978-1416054542.

[4] URL: http://moon.ouhsc.edu/kfung/jty1/Com08/Com801-1-Diss.htm. Accessed on: 3 November 2010.

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