Path review exam 2 (no picture sorry)

What term is described as the reaction of vascularized living tissues to local injury?

Inflammation

A horse receiving NSAIDs develops multifocal renal papillary necrosis. The necrotic areas become red and swollen as inflammatory cells enter the tissue. What process was initiated by the necrosis?

Inflammation

A cow with vegetative valvular endocarditis develops bacterial emboli that lodge in the kidneys. Necropsy reveals multiple areas of pus surrounding pale necrotic tissue. What two processes are occurring?

Suppurative inflammation (pus) from neutrophils actions on bacteria and coagulative necrosis from bacterial embolism of the kidney

What are the 5 cardinal signs of inflammation?

1. Heat (calor) 2. Redness (rubor) 3. Swelling (tumor) 4. Pain (dolor) 5. Loss of function (functio laesa)

A dog presents with a red, warm, swollen paw following an injury. What vascular changes are primarily responsible for these inflammatory signs?

Vasodilation and increased vascular permeability

A dog develops rapid pancreatic inflammation characterized by edema and large numbers of neutrophils. What type of inflammation is present?

Acute inflammation

A dog has an inflammatory lesion that persists because the causative stimulus was not eliminated. Neutrophils are gradually replaced by macrophages and lymphocytes. What has the inflammation become?

Chronic inflammation

A dog has long-standing pancreatitis. Histology reveals lymphocytes, macrophages, tissue destruction, new blood vessels, and extensive fibrosis. What type of inflammation is present?

Chronic inflammation

A dog develops severe facial swelling immediately after exposure to an allergen. The inflammatory response itself is responsible for the tissue changes. What harmful inflammatory primary process is occurring?

Anaphylaxis

A dog develops discoid lupus erythematosus with inflammatory destruction of tissue caused by its own immune response. What type of harmful inflammation is this?

Immune-mediated inflammation

A cow develops bacterial mastitis. Inflammation causes additional tissue damage while attempting to eliminate the infection. What harmful effect of inflammation does this demonstrate?

Worsening of an infectious process

A cow chronically exposed to a toxic plant develops chronic hepatitis. On necropsy, the liver contains multiple nodules with extensive fibrosis/scarring. During a field visit, you identify the plant responsible (show in the picture). What plant/toxin was the cow exposed to, and what complication of chronic inflammation occurred?

Heliotrope (pyrrolizidine alkaloids) NOTE: I won't ask the plant toxin or plant, but would expect you to know it's a chronic disease resulting in liver cirrhosis

A dog has chronic granulomatous esophagitis caused by Spirocerca lupi. Years later, a fibrosarcoma develops at the affected site. What consequence of chronic inflammation does this demonstrate?

Predisposition to cancer

A pathologist examines a severe inflammatory kidney lesion. To formulate the complete morphologic diagnosis, what five features must be described?

Organ, process, distribution, duration, and extent/severity

What does organ + osis indicate?

Non-inflammatory disease

A dog has inflammation involving the entire kidney. Which term should be used in the morphologic diagnosis?

Nephritis

What is inflammation of adipose tissue called?

Steatitis/panniculitis

What is inflammation of a gland called?

Adenitis

What is inflammation of a salivary gland called?

Sialadenitis

What is inflammation of the intestine called?

Enteritis

A cat has renal inflammation centered primarily on the tubules and surrounding interstitium. What is the morphologic diagnosis?

Tubulointerstitial nephritis

A dog develops an ascending bacterial urinary infection. Histology shows inflammation centered on the renal pelvis. What is the morphologic diagnosis?

Pyelonephritis

A dog has inflammation involving both the trachea and bronchi. What is the diagnosis?

Tracheobronchitis

A calf develops a bacterial respiratory infection centered on the bronchi/bronchioles and surrounding alveoli. What pattern of pneumonia is most likely?

Bronchopneumonia

A dog undergoes abdominal surgery, and the veterinarian notices yellow-white to pale tan, stringy, elastic material covering the intestinal surfaces, giving them a rough, irregular appearance. Histology reveals a thread-like eosinophilic meshwork formed after increased vascular permeability allowed fibrinogen to escape and polymerize into fibrin within minutes. What type of inflammation is present?

Fibrinous inflammation

A cow develops acute inflammation following endothelial and basement membrane injury. Plasma proteins leak into the surrounding tissues, and fibrinogen polymerizes into fibrin within minutes. What vascular change caused this exudate?

Increased vascular permeability

A dog develops fibrinous peritonitis. During recovery, small fibrin deposits disappear through enzymatic breakdown and macrophage activity. What processes are responsible for removing the fibrin?

Fibrinolysis and macrophage phagocytosis.

During necropsy, a veterinarian compares two animals. One has an acute yellow-white fibrillar exudate, while the other has chronic collagen-rich scar tissue produced by fibroblasts. What are the two processes?

Fibrinous inflammation and fibrosis

A cow develops blackleg caused by Clostridium chauvoei. Histology reveals extensive tissue destruction with relatively mild inflammation and little leukocyte infiltration. What type of inflammation is present?

Necrotizing inflammation

Which inflammation type is often associated with ischemia or toxin-producing bacteria?

Necrotizing inflammation

A bison develops severe tracheitis. During necropsy, a firmly attached pseudomembrane consisting of fibrin and necrotic epithelial tissue covers the tracheal mucosa. What type of inflammation is present?

Fibrinonecrotic tracheitis

A pig develops severe enteritis due to Lawsonia intracellularis. Necrosis of the intestinal mucosa and fibrin accumulation produce a yellow-white cast that fills part of the intestinal lumen. What type of inflammation is present?

Fibrinonecrotic enteritis

A dog develops a bacterial wound infection. The affected tissue contains thick, creamy pus composed primarily of neutrophils and dead tissue cells causing necrosis. What type of inflammation is present?

Suppurative (purulent) inflammation

A dog develops a localized bacterial infection that persists for several weeks. Necropsy reveals a cavity filled with neutrophils and cellular debris, surrounded by a thick connective tissue capsule. What lesion has developed?

Chronic abscess

A cat presents with fever and difficulty breathing. Thoracocentesis reveals thick purulent fluid containing numerous neutrophils in the pleural cavity. What condition is present?

Pyothorax

A cow develops severe pneumonia. Histology reveals abundant fibrin mixed with neutrophils in the alveolar spaces, while fibrin also covers the pleural surface. What type of inflammatory exudate is present?

Fibrinosuppurative exudate

A cow develops a persistent infection with Mycobacterium species. Necropsy reveals multiple firm, pale nodules containing macrophages, multinucleated giant cells, and central caseous necrosis. On histology reveals clusters of macrophages surrounding organisms that cannot be readily eliminated. What type of inflammation is present?

Granulomatous inflammation

A cow develops chronic diarrhea and progressive weight loss. Necropsy reveals thickened intestinal mucosa with segmental granulomatous enteritis. Acid-fast organisms are detected in tissue sections. What disease and causative agent are most likely?

Johne's disease - Mycobacterium avium subsp. paratuberculosis

A rabbit dies suddenly after developing severe systemic hemorrhage. Necropsy reveals extensive vascular injury, vessel-wall necrosis, and marked leakage of red blood cells. Which inflammatory pattern is present?

Hemorrhagic inflammation

A cat develops an acute respiratory infection with a runny nose and clear, watery discharge containing relatively few inflammatory cells. What type of inflammatory exudate is most consistent with this presentation?

Serous exudate

A dog develops an upper respiratory infection. The nasal mucosa produces abundant thick, sticky mucus containing variable numbers of inflammatory cells looks like snotty. What type of exudate is present?

Mucoid exudate

A cat presents with a respiratory infection and thick nasal discharge containing abundant mucus mixed with pus. What type of exudate is present?

Mucopurulent exudate

A calf develops inflammation of the respiratory mucous membranes with markedly increased mucus production and exudation. What type of inflammation is present?

Catarrhal inflammation

A horse develops a parasitic infection. Tissue biopsy reveals abundant eosinophils, and the inflammatory exudate has a slight greenish appearance due to cellular granules. What type of inflammation is present?

Eosinophilic inflammation

A dog presents with respiratory disease. Necropsy reveals multiple pale nodules scattered throughout the lungs, with normal lung tissue separating each nodule. Histology reveals granulomatous inflammation caused by Blastomyces dermatitidis. What is the distribution of inflammation?

Multifocal

A cat with feline infectious peritonitis (FIP) develops numerous inflammatory lesions in the kidneys. Some lesions remain separate, while others merge into larger areas of inflammation. What is the distribution of these lesions?

Multifocal to coalescing

A cow develops bacterial bronchopneumonia caused by Pasteurella multocida. Necropsy reveals severe suppurative inflammation affecting a large continuous portion of the lung, while the remaining tissue appears relatively normal. What is the distribution of inflammation?

Locally extensive

A cow is exposed to the herbicide paraquat and develops severe toxic pneumonia. At necropsy, the entire lung is red, rubbery, and affected by interstitial inflammation. What is the distribution of inflammation?

Diffuse

A dog is stung by a bee and rapidly develops anaphylactic shock. The dog dies within two hours, and necropsy reveals hyperemia, mild edema, and hemorrhage with very few inflammatory cells. What is the duration classification?

Peracute inflammation

A swan infected with highly pathogenic avian influenza (H5N1) dies suddenly. Necropsy reveals multifocal hemorrhages involving the heart, including the epicardium, with minimal inflammatory infiltration. What is the duration classification?

Peracute inflammation

A dog develops a bacterial skin infection. Within 24 hours and last for 5 days, the affected area becomes red, warm, swollen, and painful, with reduced function. Histology reveals edema, hyperemia, and numerous neutrophils. What duration of inflammation is present?

Acute inflammation

A dog develops intestinal inflammation lasting approximately one week. Histology reveals a mixed inflammatory infiltrate dominated by lymphocytes and plasma cells, reduced vascular injury, and no fibrosis or angiogenesis. What is the duration classification?

Subacute inflammation

A cow develops chronic diarrhea and progressive weight loss over several months. Intestinal biopsy reveals granulomatous inflammation, macrophages, multinucleated giant cells, and evidence of tissue remodeling. Histology reveals lymphocytes, plasma cells, macrophages, fibroblasts, collagen deposition, and newly formed capillaries. What duration of inflammation is present?

Chronic inflammation NOTE: In all likelihood, unless it's someone's pet or a very valuable breeding animal, you wouldn't do a biopsy on a cow. However, if you did, you only need to write "biopsy reveals" with one of those descriptions you have listed. Both are representative of chronic inflammation.

A cow develops Johne's disease caused by Mycobacterium avium subsp. paratuberculosis. Necropsy reveals severe granulomatous inflammation affecting a segment of the intestine. What is the morphologic diagnosis?

Severe segmental chronic granulomatous enteritis

A dog develops a persistent fungal skin infection caused by Blastomyces species. Skin biopsy reveals multiple granulomas containing macrophages and multinucleated giant cells. What is the morphologic diagnosis?

Chronic multifocal granulomatous dermatitis

A horse develops a chronic inflammatory wound. Histology reveals numerous small newly formed blood vessels, fibroblasts, and collagen deposition. What process is responsible for new blood vessel formation?

Angiogenesis (neovascularization)

What note was given about fibrosis and exudate duration?

Any exudate plus fibrosis equals chronic

A dog develops recurrent bacterial skin infections over several months. Histology reveals fibrosis, newly formed blood vessels, lymphocytes, macrophages, and numerous neutrophils from a recent inflammatory episode, fobrosis, and angiogenesis. What type of inflammation is present?

Chronic-active inflammation

A veterinarian examines a dog with a small inflammatory lesion involving only a tiny portion of the affected tissue, with little tissue damage. How would the severity most likely be classified?

Minimal or mild

A cow develops extensive pneumonia with pronounced inflammatory infiltration and substantial tissue damage. The veterinarian considers the lesion highly severe. Which severity descriptors may be used?

Marked or severe

A veterinarian evaluates two dogs with inflammatory lesions. One has limited cellular infiltration and minimal tissue damage, while the other has extensive destruction and abundant inflammatory cells. Which aspect of the morphologic diagnosis distinguishes the degree of inflammation?

Severity

A dog is brought to the emergency clinic after suffering a deep bite wound. The area becomes red, warm, swollen, and painful, and the dog has difficulty using the affected limb. The injury triggers vascular changes and recruitment of inflammatory cells to the damaged tissue. What type of inflammatory response is occurring?

Acute inflammation

A cat develops a bacterial infection following surgery. The affected tissue becomes red and warm as histamine and nitric oxide act on vascular smooth muscle, increasing blood flow through arterioles, capillaries, and postcapillary venules. What vascular event is responsible?

Vasodilation

A horse develops swelling around an infected wound. Fluid and plasma proteins escape from the microvasculature into surrounding tissues, causing edema. What is the hallmark vascular change of acute inflammation?

Increased vascular permeability

What are the 5 mechanisms of increased vascular permeability?

1. Endothelial retraction 2. Direct endothelial injury 3. Leukocyte-dependent injury 4. Increased transcytosis 5. Leakage from new capillaries

A dog develops an allergic reaction after a bee sting. Histamine, bradykinin, and leukotrienes cause endothelial cells in venules to contract, widening intercellular junctions. The reaction begins rapidly, is reversible, and lasts approximately 15-30 minutes. Which mechanism of increased vascular permeability is involved?

Endothelial cell retraction

A horse suffers severe burns involving a large portion of its body. Endothelial cells undergo necrosis and detachment, causing immediate vascular leakage that persists until the vessels are repaired or thrombosed. Which mechanism is responsible?

Direct endothelial injury

A dog develops severe bacterial pneumonia. Neutrophils adhere to endothelial cells and release reactive oxygen species and proteolytic enzymes, causing additional vascular damage during the later stages of inflammation. Which mechanism is responsible?

Leukocyte-dependent endothelial injury

A cat develops acute inflammation with increased movement of fluid through endothelial cells. Histamine and vascular endothelial growth factor increase the number and size of interconnected pinocytic vesicles and vacuoles. Which mechanism of vascular permeability is occurring?

Increased transcytosis

A horse is recovering from a traumatic wound. New capillaries develop during tissue repair, but their proliferating endothelial cells are immature and allow plasma proteins and fluid to escape. Which mechanism causes the leakage, and what mediator promotes it?

Leakage from new capillaries and mediated by VEGF NOTE: To be clear, VEGF promotes neovascularization, and these new vessels are leaky by nature

Which 3 mechanisms can occur together in thermal burns?

1. Direct endothelial injury (heat) 2. Endothelial retraction (histamine/cytokines) 3. Leukocyte injury (ROS/enzymes)

A dog develops abdominal fluid accumulation due to increased hydrostatic pressure. Fluid analysis reveals very low protein and few inflammatory cells, with no evidence of significant endothelial injury. What type of fluid is present?

Transudate

A cat develops bacterial peritonitis. Endothelial gaps widen, allowing protein-rich fluid and numerous leukocytes to escape into the abdominal cavity. What type of fluid is present?

Exudate

What disease is an example of protein-rich, cell-poor modified transudate?

Feline infectious peritonitis (FIP)

What are the etiology of exudate and transudate?

- Exudate - inflammation or infection (increase vascular permeability) - Transudate - non-inflammatory edema

A dog develops a severe bacterial wound infection. Within hours, highly mobile leukocytes arrive first, engulf bacteria, and destroy them using reactive oxygen species and proteolytic enzymes. These cells do not divide or return to circulation after entering tissues. Which inflammatory cells are responsible?

Neutrophils

A dog develops an acute bacterial infection. A blood sample reveals neutrophils distributed among circulating, marginating, and storage pools. Which three neutrophil pools are involved?

Circulating, marginating, and storage pools

A cat develops a bacterial abscess. Neutrophils engulf bacteria and release reactive oxygen species, hydrogen peroxide, and lysosomal enzymes. The same substances can also damage surrounding healthy tissues. What are the major antimicrobial mechanisms involved?

Phagocytosis, ROS, and lysosomal enzymes

What are the major neutrophil functions?

Phagocytosis, tissue injury, and regulation of inflammation

Where is myeloperoxidase located in neutrophils?

Azurophil granules NOTE: I wouldn't ask for the specific granule type, just that they contain MPO (myeloperoxidase) in their cytoplasmic granules

When do neutrophils predominate?

Acute inflammatory reactions and suppurative/purulent exudates (especially bacterial infections)

A chicken develops a bacterial infection, and the veterinarian identifies leukocytes containing prominent eosinophilic granules. These cells perform functions similar to mammalian neutrophils but lack myeloperoxidase. Which cells are present?

Heterophils

A reptile develops severe bacterial inflammation. Histology reveals numerous granulocytes that resemble eosinophils but serve as the primary neutrophil equivalent in this species. Which inflammatory cells are involved?

Heterophils

A horse develops a severe intestinal helminth infection. Histology reveals abundant eosinophils recruited by IL-5 and histamine. These cells release toxic granule proteins that damage parasites. Which two granule proteins are primarily involved?

Major basic protein and eosinophil cationic protein

What are the major eosinophil granule contents listed?

Major basic protein and histaminase (MBP)

What does histaminase do?

Anti-inflammatory and inactivates histamine

A dog develops an allergic skin reaction following repeated exposure to an environmental allergen. Eosinophils accumulate in the tissue and contribute to the hypersensitivity response. Which type of hypersensitivity is particularly associated with eosinophils?

Type I hypersensitivity

A cat develops parasitic inflammation involving the intestines. Eosinophils bind antibody-coated parasites and release toxic granule proteins to damage them. What immune mechanism is responsible?

Antibody-dependent cell-mediated cytotoxicity (ADCC)

A dog with eosinophilic inflammation receives corticosteroid therapy. The veterinarian observes a decrease in circulating eosinophils due to reduced release from the bone marrow. Which drug class caused this effect?

Corticosteroids

When do eosinophils predominate?

Parasitic diseases, hypersensitivities, and rare autoimmune conditions NOTE: Most autoimmune diseases are mediated by lymphocytes and plasma cells

A dog develops an acute allergic reaction after exposure to pollen. Antigens bind IgE on tissue-resident cells, triggering the release of histamine, proteases, and inflammatory mediators. The cells are abundant around blood vessels and do not circulate. Which cells are responsible?

Mast cells

A cat develops a Type I hypersensitivity reaction. The veterinarian identifies rare circulating granulocytes containing metachromatic granules that stain magenta with toluidine blue and contain histamine. Which cells are involved?

Basophils

A cow develops a persistent bacterial infection. Circulating monocytes migrate into the tissue and differentiate into long-lived phagocytic cells that remove debris, release cytokines, and recruit additional leukocytes. Which cells are responsible?

Macrophages

A dog develops chronic inflammation around foreign material embedded in the skin. Mononuclear become activated and differentiate into epithelioid cells and multinucleated giant cells. Which inflammatory cells are the precursors?

Macrophages

A cat develops chronic viral inflammation. Histology reveals Mononuclear involved in antibody production, delayed cellular hypersensitivity, and immune regulation. Which inflammatory cell populations predominate?

Lymphocytes and plasma cells

Which canine disease causes lymphocytes and plasma cells?

Distemper

A dog develops an inflammatory reaction following vascular injury. What type of cells release inflammatory mediators, express P-selectin to facilitate leukocyte migration, and activate complement component C5. Which blood components are contributing to inflammation?

Platelets

A horse develops acute inflammation after a wound. What type of cells release prostaglandins, prostacyclin, platelet-activating factor, IL-1, IL-8, and nitric oxide while expressing adhesion molecules for leukocyte migration. Which cells coordinate these vascular inflammatory responses?

Endothelial cells

What anti-inflammatory and pro-repair mediator do endothelial cells produce?

TGF-beta NOTE: remember macrophages are the primary cells that produce this

A dog develops chronic inflammation following a deep tissue injury. Fibroblasts produce IL-6 to stimulate Band T-cell proliferation and TGF-β to promote repair and regulate inflammation. Which cells are responsible?

Fibroblasts NOTE: These are produced primarily by macrophages and to a lesser extent endothelial cells. They act on fibroblasts. See lecture 9, slide 17.