Page "Fibrinoid necrosis" Paragraph 2

Fibrinoid material does usually contain fibrin and tends to be eosinophilic ( staining red with the acidic dye eosin ).

However, in systemic lupus erythematosus the fibrinoid deposits may contain significant amounts of nuclear debris, including acidic DNA, and may be haematoxyphilic ( staining purple or blue with the basic dye haematoxylin ).

Fibrinoid necrosis is distinguished from hyaline deposits, which are more homogeneous and glassy, and caseous necrosis, which is associated with the tuberculosis.

Fibrinoid is now a somewhat historic term, based on traditional haematoxylin and eosin staining.

Its significance is different in different contexts, such as malignant hypertension and rheumatoid nodules.

However, in context it remains a diagnostically useful term.

The idea that autoimmune diseases such as systemic lupus and rheumatoid arthritis were based on a common lesion of ' fibrinoid necrosis of collagen ' led to the popular term ' collagen vascular disease ', which is now obsolete.

It is cells that are dead, not collagen.

The presence of fibrin indicates that nearby blood vessels have become highly permeable and often themselves destroyed but vasculitis is not necessarily present at sites of fibrinoid deposition.