Caseous necrosis or caseous degeneration () appearing as a soft and white proteinaceous dead cell mass. The dead tissue is enclosed within a granuloma, and differs from coagulative necrosis in that tissue structure is destroyed. Caseous necrosis is most notably associated with tuberculoma.
The term caseous means 'pertaining or related to cheese', and comes from the Latin word 'cheese'.
Histology
thumb|Caseous necrosis in the kidney
In caseous necrosis no histological architecture is preserved (unlike with coagulative necrosis). On microscopic examination with H&E staining, the area is acellular, characterised by amorphous, roughly granular eosinophilic debris of dead cells,
Causes
Caseous necrosis is characteristically associated with tuberculomas.
Pathophysiology
The process begins as infection is recognized by the body and macrophages begin walling off the microorganisms or pathogens. As macrophages release chemicals that digest cells the cells begin to die. As the cells die they disintegrate but are not completely digested and the debris of the disintegrated cells clumps together creating soft granular mass that has the appearance of cheese.
Some data suggests that host macrophages associated with granulomas may prevent effective immune clearance of mycobacteria, due to their epithelioid morphology and associated barrier function.
References
External links
- Microscope images of caseous necrosis
- Image of a hilar lymph node demonstrating caseous necrosis
- Image of a caseating granuloma of tuberculosis in the adrenal gland