Inflammation and Necrosis

Necrosis and Inflammation

• Example – Nephritis in Broiler Breeders• Multifocal Lesions• Tubular Necrosis and Heterophilic Inflammation

• Regenerative Hyperplasia of Tubular Epithelium

• Expansion of Interstitial Connective Tissue 

PresenterPresentation NotesThis case from broiler breeders illustrates multifocal tubular necrosis and heterophilic nephritis causing and expansion of the interstitial connective tissue. Also shown are hyperplasia of renal tubular epithelium that characterizes regenerative repair following injury.

A B

C D

PresenterPresentation NotesImage A is a low power view of kidney that shows dilated tubules.Image B shows expansion of interstitial tissue by edema and inflammatory cells , mostly heterophils, and necrosis of tubules. The area enclosed by the box is shown at higher magnification in C. The pink-stained structure is a renal tubule with necrotic epithelial cells. Adjacent tubules also are necrotic. The area enclosed by the circle is shown at higher magnification, within the oval, in D. Hyperplasic epithelial cells indicate regeneration of tubular epithelium.In both images C and D, heterophils can be seen.

A B

C D

PresenterPresentation NotesImages A and B show tubular necrosis and heterophilic inflammation. Some tubular regeneration is seen in B.Images C and D show heterophilic inflammation.

Lymphocytic Nephritis

• Broiler Breeders – Increase in Mortality and Drop in Production

• Lesions Suggest IBV• Other Possibilities Include:

– Water Deprivation– Excess Ca Diet for Birds Not Laying Eggs

PresenterPresentation NotesLymphocytic nephritis in broiler breeders in this case could be due to infection with bronchitis virus. Other rule outs or differential diagnoses include water deprivation and excess calcium in the diet, if these hens were out of production and consuming a high calcium ration.

A B

C D

PresenterPresentation NotesA shows a focal tubule with mineral deposition and expansion of interstitial tissue by lymphocytes. B is a higher magnification of the mineralized tubule.C and D show lymphocytes expanding interstitial tissue.

Fibrosis in Kidney

• Broiler Breeders• Increased Mortality and Drop in Production• Expansion of Interstitial Tissue in Medullary Cone Due to Increase in Fibrous Tissue

PresenterPresentation NotesThis case used to illustrate fibrosis comes from broiler breeders experiencing increased mortality and egg production drops. You will see that interstitial tissue of the kidney is expanded resulting in tubules being further apart than normal. This expansion is due largely to proliferation of fibrous connective tissue.

A B

C D

PresenterPresentation NotesImages A-D are progressively higher magnifications of kidney that show the separation of tubules by fibrous tissue that is expanding the interstitial tissue. This is an example of chronic nephritis.

Fibrosis ‐ Liver

• Lori– 7 Years

• Also had Atherosclerosis• Multifocal, Variable‐Sized, Accumulations of Fibrous Tissue Replacing Hepatocytes

PresenterPresentation NotesIn this case, the liver from a 7 year-old Lori has multiple, variably-sized areas of fibrosis. This is an example of multifocal fibrosing hepatitis, also called multifocal chronic hepatitis. The cause was unknown, but may have been related to severe atherosclerosis that led to chronic hypoxia with subsequent necrosis and fibrosis.

A B

C D

PresenterPresentation NotesImages A-D are progressively higher magnifications of liver that show multiple, variable-sized, relatively acellular and eosinophilically stained areas of fibrosis.

A B

C D

PresenterPresentation NotesImages A and B are H&E stained sections showing a focal area of fibrosis. Images C and D are trichrome-stained sections showing collagen that stains blue with this special stain.

Degenerative Changes

Fatty Change

PresenterPresentation NotesHepatic Lipidosis - Cockatiel

Hydropic Change

PresenterPresentation NotesHydropic Change – PoxAlso note I/C inclusions

Necrosis

Gross Lesion ‐ Encephalomalacia

PresenterPresentation NotesBrain - Encephalomalacia

Liquifactive Necrosis

Encephalomalacia

Vitamin E Deficiency

PresenterPresentation NotesLiquifactive NecrosisEncephalomalacia – Vitamin E Deficiency

Caseous Necrosis

PresenterPresentation NotesVaccine Reaction – Caseous Necrosis

Vaccine Reaction

Caseous Necrosis

PresenterPresentation NotesVaccine Reaction – Caseous Necrosis

Caseous Necrosis ‐ Lung

Aspergillosis

PresenterPresentation NotesLung – AspergillosisCaseous Necrosis

Caseous Necrosis ‐ Lung

Aspergillosis

PresenterPresentation NotesLung – AspergillosisCaseous NecrosisD is a GMS stain to demonstrate fungi

Hepatic Necrosis

Multifocal

Bacterial Septicemia

PresenterPresentation NotesLiver – Multifocal NecrosisBacterial Septicemia

Fibrinoid Necrosis

Liver ‐ Salmonellosis

PresenterPresentation NotesLiver – Fibrinoid NecrosisSalmonella but could be any bacterial infection including E. coli

Inflammation and NecrosisNecrosis and InflammationSlide Number 3Slide Number 4Lymphocytic NephritisSlide Number 6Fibrosis in KidneySlide Number 8Fibrosis - LiverSlide Number 10Slide Number 11Degenerative ChangesFatty ChangeHydropic ChangeNecrosisGross Lesion - EncephalomalaciaLiquifactive NecrosisCaseous NecrosisVaccine ReactionCaseous Necrosis - LungCaseous Necrosis - LungHepatic NecrosisFibrinoid Necrosis