Pathology Exam 1: Types of Necrosis

Ischemia caused by obstruction in a vessel may lead to coagulative necrosis of the supplied tissue in all organs except the _________?

Brain

General term resembling coagulated protein or curds?

Caseous

Localized and well demarcated; soft, friable, gray-tan material resembling cheese; dry and crumbly or soft and pasty; +/- gritty on cutting due to mineralization; +/- laminated on cross-section (especially C. pseudotuberculosis) are all gross appearances of what type of necrosis?

Caseous

The presence of neutrophils (does/doesn't) equate to an abscess?

doesn't

Sequelae of an infarct include death due to organ ___________ or scarring

dysfunction

What two bacteria commonly cause caseous necrosis?

mycobacterium bovis, corynebacterium pseudotuberculosis

Microscopic appearance of an abscess: large numbers of __________ and necrosis of parenchyma

neutrophils

Is there a known treatment for leukoencephalomalacia?

no, sorry 'bout ya

In the CNS, the tissue lacks __________ so there is no coagulation involved with the characteristic pattern of ischemic necrosis of liquefactive necrosis

proteins

Abscesses can occur anywhere, and are elicited by certain bacterial agents that are ____________, meaning they attract neutrophils

pyogenic

Staphylococcus, Streptococcus, and Corynebacterium are all ________ bacterium, they cause abscesses

pyogenic

Liquefactive necrosis CNS sequelae: _________ of debris by phagocytes

removal

Polioencephalomalacia is a disease of what species?

ruminants

Deficiency of thiamine results in a reduction in the __________________ and subsequent loss of osmotic control

sodium-potassium pump

Build-up of what in leukoencephalomalacia causes direct cellular toxicity?

sphinganine

The inhibition of ceramide synthase leads to decreased production of what and toxicity from what?

sphingolipids, sphinganine

Ingestion of high _________-containing diets, can result in the cleaving of thiamine into constituents thereby rendering it inactive, leading to polioencephalomalacia

sulfur

Dietary deficiency of what can lead to polioencephalomalacia?

thiamine

Caseous necrosis microscopic appearance: center of lesion (with/without) cell or tissue architecture?

without

Fumonisin B1 binds to and inhibits what enzyme?

Ceramide Synthase

A lesion in polioencephalomalacia that gives a yellow color to the gray matter is termed?

Cerebral laminar necrosis

Ergotamine is produced by what fungus? The fungus infects seed heads of grasses.

Claviceps purpurea

What is the name of the organism that causes Malignant edema in ruminants?

Clostridium septicum

Acute anoxia (e.g. ischemia), acute toxic injury, certain bacterial and viral agents are all causes of what type of necrosis?

Coagulative

Form of necrosis in which the architecture of dead tissues is preserved for a span of at least some days. Preservation of basic cell outlines.

Coagulative

Removal of debris with scarring or regeneration are sequelae of what type of necrosis?

Coagulative

What form of necrosis blocks the proteolysis of the dead cells because the injury denatures not only structural proteins but also enzymes?

Coagulative

What bacteria causes ovine caseous lymphadenitis?

Corynebacterium pseudotuberculosis

Ergot poisoning, which causes chronic vasoconstriction, has lesions which begin at the coronary band and results in ______ gangrene?

Dry

Freezing--> vasoconstriction and increased blood viscosity--> hypoxia/anoxia (of extremities)--> ________ gangrene

Dry

Salmonellosis in pigs--> endotoxin damages blood vessel--> endothelial damage +/- fibrinoid degeneration--> thrombosis and vasculitis--> ______ gangrene

Dry

What type of gangrene has a gross appearance more like coagulative necrosis?

Dry

Gross appearance of what type of necrosis would be described as a dry area, shriveled, leathery, dark red to black

Dry gangrene

Microscopic appearance of what necrosis type is described as similar to coagulative necrosis, and has a line of demarcation caused by leukocytes

Dry gangrene

What type of necrosis has a gross description of being cold, lacks sensation. Red line of demarcation between necrotic and viable tissue

Dry gangrene

What causes direct stimulation of the arteriolar smooth muscle resulting in marked vasoconstriction; leading to ischemic necrosis?

Ergot poisoning

What is caused by the ingestion of toxic alkaloids (ergotamine) produced by the fungus Claviceps purpurea?

Ergot poisoning

Necrosis of adipose tissue to to action of lipases is termed?

Fat necrosis

The microscopic appearance of what type of necrosis may have an outline of adipocytes present, fat replaced with amorphous granular material with variable staining (material represents fatty acid soaps), inflammation (PMNs, macrophages) and fibrosis?

Fat necrosis

What type of necrosis is often found near the pancreas or in the peritoneal cavity (near enzymes involved in breaking down fat)?

Fat necrosis

What type of necrosis is often found with pancreatitis?

Fat necrosis

Fumonisin B1 toxin is produced by what fungus on moldy corn? What color is it?

Fusarium verticilloides, pink

Ischemia, aspiration pneumonia due to inhalation of irritating gastric contents, bacterial toxins (especially mastitis) are all causes of what?

Gangrene

Death due to toxemia, especially when internal organs are affected (GI twists); sloughing, especially when external tissues are affected are all sequelae of what type of necrosis?

Gangrenous

Type of necrosis that represents ischemic injury modified to varying degrees by exposure to air (dry) or by the liquefactive action of bacteria (moist or wet). Clinical term.

Gangrenous

The following are microscopic findings you would see with what disease? early: edema, necrosis of neuronal cell bodies, and endothelial cell swelling later: loss of neurons and vacuolation of the neuropil after 7-10 days: macrophages (gitter cells) invade the area to ingest the myelin and cell debris

Polioencephalomalacia

Thiamine deficiency (carb overload, eating Bracken Fern) ----> decreased energy-----> decreased Na-K pump--> loss of osmotic control--> necrosis of neurons; is the pathogenesis of what disease?

Polioencephalomalacia

Abscess sequelae: abscess--> bacterial emboli spread via blood--> disseminated abscess--> +/- death due to septicemia. This is the pathogenesis of what?

Pyemia

Abscess sequelae: abscess walled off--> resorption of debris +/- mineralization-> scar. This is the pathogenesis of what?

Resolution

Plant toxins, bacteria, vitamin E- Selenium deficiency, exertional ("capture") myopathy, and ischemia are all potential causes of what?

Zencker's necrosis

Zencker's necrosis is a type of what necrosis?

coagulative

Coagulative necrosis of striated muscle is termed?

Zencker's necrosis

Hemorrhage and myonecrosis due to bacterial toxins leading to gas bubbles in muscle is the pathogenesis of what disease?

Blackleg

What is the name of the disease of ruminants caused by Clostridium chauvoei?

Blackleg

Regarding leukoencephalomalacia: ________ percent of exposed animals are affected and they death rate is high in affected horses

25

A localized area of coagulative necrosis is called?

Infarct

Thiamine also serves as coenzymes in the ________ cycle?

Krebs

What disease is caused by ingestion of fumonisin B1 toxin produced by the fungus Fusarium verticilloides on moldy corn?

Leukoencephalomalacia

A type of necrosis characterized by tissue that has liquefied due to the action of hydrolytic enzymes, primarily from neutrophils?

Liquefactive

Myelomalacia due to ruptured intervertebral discs (dogs), equine leukoencephalomalacia, and polioencephalomalacia (ruminants) are all examples of what type of necrosis?

Liquefactive

Edema and hemorrhage (due to bacterial toxins), as well as gas in subcutis and fascial planes of muscles is the description of what disease?

Malignant edema

What is the name of the disease of ruminants caused by Clostridium speticum?

Malignant edema

What type of fat has a gross appearance of opaque, white, firm to hard, granular gritty on cutting?

Mesenteric

What bacteria causes TB?

Mycobacterium bovis

Abscess sequelae: bacteria plus bacterial toxins in the blood can cause hemodynamic changes and/or cell injury (sepsis). This is the pathogenesis of what?

Septicemia

what type of fat has a gross appearance of opaque, yellow to brown (due to ceroid pigment), firm, lumpy?

Subcutaneous

Bacteria that produce what can proliferate after CHO ingestion leading to polioencephalomalacia?

Thiaminase

Plants producing what, such as Bracken Fern, can result in Polioencephalomalacia?

Thiaminase

In regards to polioencephalomalacia, treatment of early cases consists of administration of what and can be quite successful?

Thiamine

Polioencephalomalacia is thought to be cause be a deficiency of what?

Thiamine

Intestinal twisting along longitudinal axis is termed?

Torsion

Multinucleated giant cells are characteristic of what disease?

Tuberculosis

Intestinal twisting around its mesenteric attachment is termed?

Volvulus

_________ gangrene has a gross appearance like liquefactive necrosis

Wet

Microscopic appearance of what necrosis type is described as coagulative + liquefactive necrosis, +/- gas bubbles, line of demarcation

Wet gangrene

The gross appearance of what type of necrosis is tissue dark red to black; soft, moist, friable; foul odor; +/- gas bubbles, crepitant on palpation (gas gangrene); line of demarcation

Wet gangrene

A localized collection of pus (liquid inflammatory debris) is termed?

abscess

Center with granular, eosinophilic debris, basophilic nuclear remnants, basophilic material are all microscopic appearance of what type of necrosis?

caseous

Encapsulation and persistence; or healing by scarring all sequelae of what type of necrosis?

caseous

Periphery with macrophages, other inflammatory cells +/- fibrous connective tissue is a microscopic appearance of what type of necrosis?

caseous

What type of necrosis is characteristic of certain bacterial infections and has a distinct appearance?

caseous

Polioencephalomalacia: undigested membrane debris remains within the macrophages as ________ pigment; this fluoresces under UV light

ceroid

The initial change in a polioencephalomalacia lesion is ___________, as evidenced by swelling of gyri.

edema

Microscopic apearance of CNS liquefactive necrosis: decreased density of tissue, pale ____________, poorly defined edges, +/- phagocytic cells (Gitter cells)

eosinophilia

Microscopic appearance of an abscess: ___________ capsule, mineralized debris in older lesions

fibrous

Leukoencephalomalacia is caused by the ingestion of what toxin?

fumonisin B1

Liquefactive necrosis CNS sequelae: Loss of __________- signs attributed to area(s) affected

function

Liquefactive necrosis CNS sequelae: healing by ____________- proliferation of fibrillary astrocytes, NOT fibrosis

gliosis

Thiamine is a cofactor or coenzyme in a number of important metabolic reactions. Thiamine is a cofactor in the hexose monophosphate shunt which is the major metabolic pathway for ___________ in the brain?

glucose

Leukoencephalomalacia is a disease of what species?

horses

Liquefactive necrosis in the CNS can be an abscess or suppurative inflammation, but also can have a characteristic pattern of what type of necrosis?

ischemic

In coagulative necrosis, ultimately the necrotic cells are removed by phagocytosis and by digestion of the dead cells by the action of __________ enzymes of the leukocytes?

lysosomal