Pathology is devoted to the study of structural, biochemical, and functional changes in cells, tissues, and organs that underlie disease
Pathology literally translates to the study of suffering.
Etiology or cause is the origin of the disease
Pathogenesis is the exposure of the tissue or cells to an injurious agents (mechanism)
Morphologic changes refers to the structural alteration in cells/tissues (induce in the cells and organs of the body)
Signs are the "objective” evidence of the disease [e.g, physical observation, measurable indicator]
Symptoms are the “subjective” evidence of the disease [e.g., pain, itchiness, dizziness, fatigue, and tinnitus]
Tinnitus is the abnormal ringing of the ears
Rudolf Carl Virchow is the father of Modern Pathology.
Aulus Cornelius Celsus is the one who described the first 4 cardinal signs.
FIVE CARDINAL SIGNS OF INFLAMMATION:
Rubor (redness)
Calor (heat)
Tumor (swelling)
Dolor (pain)
Functio laesa (loss of function)
Rubor is the arteriolar vesicular dilation because of blood flow due to injury
↑ concentration RBC
slow blood flow
Stack RBC causes redness in rubor
Calor is due to the transfer of internal heat to the surface or site of injury, brought about by increased blood content
blood → heat (end product)
redness automatic w/ Heat
Tumor is the increased capillary permeability, allowing the extravasation of blood fluid causing localized edema accompanied by escape of blood cells into the injured area.
Increased capillary permeability allows excrete of fluid/gases thru cell membrane, which causes edema
Edema is the excess fluid on tissue
Increased extravasation causes hydrostatic pressure within the dilated blood vessels
Dolor is the direct damage to the nerve ending; there is pressure to the sensory nerves
An example of dolor is Arthritis
Functio laesa is the pain interference with nerve supply and destruction of the functioning units; there is a limitation of movement due to swelling.
Functio laesa can be an adaptive mechanism by the body to protect the injured area from further damage.
In Acute inflammation:
onset is fast which can last minutes to hours,
cellular infiltrate is mainly neutrophils,
tissue injury is usually mild and self limited, and
local/systematic signs are prominent
In Chronic inflammation:
onset is slow which can take days,
cellular infiltrate are mononuclear cells,
tissue injury is often severe and progressive, and
local/systematic signs are less
An exudate is a fluid emitted by an organism through pores or a wound, a process known as exuding or exudation.
Serous Inflammation is a type of exudate that is an extensive outpouring of watery, low-protein fluid from either the blood serum or secretions of serosal mesothelial cells [e.g., Pulmonary TB]
Fibrinous Inflammation is a type of exudate that is an exudation of large amount of fibrinogen and precipitation of fibrin masses [e.g., Diphtheria, rheumatoid pericarditis, Early stage of pneumonia]
Catarrhal Inflammation is a type of exudate that is an hypersection of mucosa with degenerative changes in epithelium [e.g., rhinitis, gastritis, colitis]
Hemorrhagic is a type of exudate that is an admixture of blood = blood + exudates [e.g., Bacterial infections & other infections]
Purulent/Suppurative is a type of exudate that produces large amount of pus or purulent exudates.
Pus is a creamy fluid component of PMNs & necrotic tissue debris
Retrogressive changes are when organs or tissues are smaller than normal
Progressive changes are when organs or tissues are larger than normal
Degenerative changes are when there is an aberrations of cellular growth patterns
Developmental defects in retrogressive changes (AAHA):
Aplasia
Agenesia
Hypoplasia
Atresia
Atrophy is the acquired decrease in size of a normally developed/mature tissues or organs resulting from reduction in cell size or decrease in total number of cells or both
Physiological atrophy is natural, associated with thymus and sex organs
Pathologic atrophy is the consequence of a disease
Hypertrophy is the increase in size of tissues/organs due to increase in size of individual cells
Hyperplasia is the increase in size of tissues/organs due to the increase in the number of individual cells