VPATHO 101: Introduction to Pathology & Causes of Disease

Flashcards testing vocabulary definitions, branches of pathology, types of diagnosis, wound classifications, and pathological causes of disease from Dr. Atos's VPATHO 101 lecture.

Pathology

The scientific study of disease, dealing with abnormalities of body structures and functions, or the derangement of molecules, cells, tissues, and function in response to injury.

General Pathology

The branch of pathology dealing with basic processes that occur in response to injury at the tissue, cell, and molecular level.

Systemic Pathology

The application of general pathologic processes to organ and/or systemic injury, explaining how these processes manifest through specific organ lesions.

Gross Pathology

The study of disease through the examination of tissues and organs with the unaided eye; also called macroscopic pathology, pathological anatomy, or morbid anatomy.

Cellular Pathology

The study of diseased tissues and organs with the aid of a microscope; also called microscopic pathology or histopathology.

Surgical Pathology

The branch of pathology concerned with the study of tissues removed at the time of surgery, known as biopsy materials.

Clinical Pathology

The study of disease through the laboratory examination of blood, urine, feces, skin scrapings, and similar specimens.

Comparative Pathologist

A pathologist whose field of interest encompasses the diseases of all species, including humans.

Experimental Pathologist

A pathologist who manipulates, analyzes, and recreates structural and functional abnormalities to better understand underlying disease mechanisms.

Disease

A state in which an individual exhibits an anatomical, physiological, or biochemical deviation from normal, resulting in structural or functional abnormalities.

Clinical Signs

Objective, visible functional evidence of disease that can be observed or measured by an observer (e.g., vomiting, diarrhea).

Clinical Symptoms

Subjective functional evidence of disease felt and described by human patients, not applicable to animal patients (e.g., headache, nausea).

Lesions

Abnormal structural and functional changes that occur in the cells, tissues, and organs of the body as a result of injury.

Prognosis

A statement regarding the expected outcome of a disease, classified as recovery, invalidism, or death.

Pathogenesis

The developmental sequence of events involved in the cellular and tissue response to injury, extending from initial cellular injury to full disease manifestation.

Etiology

The study of the cause of disease.

Idiopathic Disease

A disease process for which the etiologic or causative agent is unknown.

Morphologic Diagnosis

A diagnosis based on the dominant gross and microscopic lesions in tissues, specifying extent, duration, distribution, and type of lesion.

Etiological Diagnosis

A diagnosis that specifies the precise causative agent (such as a specific bacterium, virus, or toxin) responsible for the disease.

Definitive Diagnosis

A conclusive diagnosis that names the exact specific disease entity involved (e.g., rabies, Johne's disease).

Differential Diagnosis

A systematically compiled list of candidate diseases that could account for a patient's clinical signs and lesions, evaluated to identify the underlying cause.

Necropsy

A gross examination of an animal carcass performed by methodical dissection.

Biopsy

The removal and diagnostic examination of tissue obtained from a living body.

Contusion

A bruise caused by the rupture of small blood vessels leading to disintegration of extravasated blood while the overlying skin surface remains intact.

Abrasion

A circumscribed area where the superficial epithelium has been removed by mechanical scraping.

Erosion

A partial loss of the surface epithelium of a mucous membrane.

Incision

A clean cut produced by a sharp-edged instrument that is longer than it is deep.

Stab Wound

A penetrating or puncture wound that is deeper than it is long, often reaching an underlying body cavity.

Laceration

A tear wound caused by dull instruments or excessive stretching that macerates and severs tissue, producing significant blood loss.

1st Degree Burn

A partial-thickness superficial thermal injury characterized by erythema and/or vesicles.

2nd Degree Burn

A partial-thickness burn in which the epidermis is destroyed while underlying skin appendages such as hair follicles and glands remain intact.

3rd Degree Burn

A full-thickness thermal injury resulting in complete necrosis through the entire layer of the epidermis.

4th Degree Burn

A severe thermal injury in which the affected tissue is charred.

Freezing

Tissue injury resulting from prolonged cold exposure, where intracellular fluid crystallizes and leaves high salt concentrations that cause tissue necrosis.

Cantharidin

The toxic chemical found in blister beetles that causes gastrointestinal irritation, ulceration, hemorrhage, and necrosis when ingested by animals such as horses.

Batrachotoxin

A potent neurotoxin associated with poison dart frogs that irreversibly blocks sodium channels in neurons, preventing nerve reset and causing membrane depolarization.

Tetrodotoxin

A toxin found in puffer fish tissues that binds sodium channels on nerve axons to suppress impulse conduction, leading to paralysis, convulsions, and death.

Aflatoxin

A group of hepatotoxic metabolites produced by Aspergillus flavus in warm, humid storage conditions; it inhibits DNA-dependent RNA polymerase in nucleoli, blocking protein synthesis.

Sporidesmin

A hepatotoxin from Pithomyces chartarum that causes bile duct occlusion and facial eczema in livestock via systemic accumulation of phylloerythrin.

Ergotism

A disorder caused by Claviceps purpurea alkaloids (ergotamine and ergometrine) on infected grains, producing ischemic gangrene in extremities due to chronic vasoconstriction.

Zearalenone

An estrogenic mycotoxin produced by Fusarium species in moldy corn that triggers precocious sexual development and vulvar enlargement in swine.

Fumonisin

A mycotoxin from Fusarium species that causes leukoencephalomalacia (liquefactive necrosis of cerebral white matter) in horses and pulmonary edema in swine.

Teratogenic Effect

An effect caused by toxins or substances during gestation that leads to structural birth defects or skeletal malformations in offspring (e.g., arthrogryposis from poison hemlock).

Cyanogenic Glycosides

Plant toxins that release free cyanide (HCN) upon hydrolysis, which binds mitochondrial cytochrome oxidase to inhibit cellular respiration, causing immediate cell hypoxia.

Prion

A proteinaceous infectious particle composed entirely of misfolded protein, lacking nucleic acids (DNA/RNA), that causes transmissible spongiform encephalopathies.

Macule

A circumscribed, discolored spot on the skin that is flat and not elevated above the skin surface.

Papule

A small, circumscribed, solid elevation of the skin.

Vesicle

A small (less than $1\,cm$), circumscribed epidermal elevation filled with clear serous fluid.

Pustule

A small, circumscribed elevation of the epidermis containing pus.

Pyogenic Bacteria

Bacteria that induce acute inflammatory responses characterized by the attraction of neutrophils and pus formation.

Endotoxin

A lipopolysaccharide component contained within the cell wall of Gram-negative bacteria, released upon bacterial breakdown to cause vascular collapse and endotoxic shock.

Exotoxin

A soluble toxic protein actively secreted by living bacteria that damages cell membranes or suppresses metabolic pathways.

Gram-Positive Bacteria

Bacteria containing thick peptidoglycan cell walls with muramic acid that retain crystal violet-iodine complex dye, staining blue/purple.

Mycosis

A disease state caused by the active, direct invasion and growth of fungal organisms within host tissues.

Mycotoxicosis

Poisoning resulting from the ingestion of toxic chemical metabolites (mycotoxins) produced by fungi, without requiring active fungal infection in the host.

Starvation

A state caused by prolonged lack of food intake, characterized by emaciation, loss of musculature, serous atrophy of fat, and visceral atrophy.

Serous Atrophy of Fat

A pathologic change seen in severe starvation where adipocytes shrink and normal fat tissue is replaced by a clear to pink, gelatinous, mucinous fluid.