Pathophysiology Introduction Flashcards
Define pathophysiology
The study of functional or physiologic changes in the body that result from disease processes
Define Pathology
The laboratory study of cell and tissue changes associated with disease
Define disease
A deviation from the normal structure or function of any part, organ, system (or combination) from a state of wellness. WHO includes physical, mental and social well-being in it’s definition of health. When homeostasis cannot be maintained without intervention.
Homeostasis
The maintenance of a relatively stable internal environment regardless of external changes
Factors that can account for variations in “normal” limits for health indicators
Age, gender, genetics, environment, activity level
Diagnosis
Refers to the identification of a specific disease through evaluation of signs and symptoms, lab test or other tools.
Etiology
The causative factors in a particular disease - congenital defects, inherited or genetic disorders, microorganisms like viruses or bacteria, immunologic dysfunction, environmental factors, nutritional deficiencies
Define idiopathic
When the cause of a disease is unknown
Define iatrogenic
When a treatment, procedure or an error may cause a disease - ex bladder infection from catheterization
Predisposing factors
The tendencies that promote development of a disease in an individual. Indicates high risk but not certain development - ex. age, gender, inherited factors, occupational exposure.
Pathogenesis
The development of the disease or the sequence of events involved in the tissue changes related to the specific disease process.
Subclinical state
Exists in some conditions in which pathologic changes occur, but no obvious manifestations are exhibited by the patient - ex. kidney damage may progress to an advanced stage before symptoms manifest.
Incubation or latent stage
Time between exposure to the microorganism and the onset of signs or symptoms
Prodromal period
The time in the early development of a disease when one is aware of a change in the body but the signs are nonspecific - ex fatigue, loss of appetite
Manifestations of a disease
Clinical evidence or effects - the signs and symptoms
Lesion
A specific local change in tissue
Syndrome
A collection of signs and symptoms, often affecting more than one organ, usually occur together in response to a certain condition
Precipitating factor
A condition that triggers an acute episode, such as a seizure. An angina attack can be precipitated by shovelling snow on a cold day.
Sequelae
The potential unwanted outcomes of the primary condition, such as paralysis following recovery from stroke
Convalescence or rehabilitation
The period of recovery and return to the normal healthy state
Prognosis
The probability or likelihood for recovery or other outcomes. Average outcomes
Morbidity
Indicates disease rates in a group
Mortality
The relative number of deaths resulting from a particular disease
Epidemiology
The science of tracking the pattern or occurrence of disease. Includes data on transmission and distribution of diseases.
Epidemics
Occur when there are a higher than expected number of cases of an infectious disease within a given area
Pandemics
Involve higher numbers of cases in may regions of the globe.
Incidence of disease
Indicates the number of NEW cases in a given population noted within a state time period
Prevalence of disease
The number of NEW and OLD or existing cases within a specific population and time period
Atrophy
A decrease in the size of cells, a reduction in tissue mass. Ex. reduced use, insufficient nutrition
Hypertrophy
Increase in the size of individual cells. Ex additional work by the tissue - enlarged heart
Hyperplasia
Increase in the number of cells resulting in an enlarged tissue mass. May be compensatory to meet increased demands or pathologic when there is a hormonal imbalance.
Metaplasia
Occurs when one mature cell type is replaced by a different mature cell type. Ex, when stratified squamous epithelium replaces ciliated columnar epithelium in the respiratory tract of cigarette smokers.
Dysplasia
Term applied to tissue in which the cells vary in size and shape, large nuclei are present and the rate of mitosis is increased. Ex. chronic irritation from infection, precancerous change. Pap smears detect dysplasia.
Anaplasia
Cells that are undifferentiated with variable nuclear and cell structures and numerous mitotic figures - cancer
Neoplasia
New growth - a neoplasm is commonly called a tumor
Gangrene
An area of necrotic tissue that has been invaded by bacteria
Infarction
An area of dead cells resulting from lack of oxygen
Endemic
Disease that is usually present in a specific region and culture
Compensatory Hyperplasia
An adaptive response that allows certain organs like the liver to regenerate
Pathologic hyperplasia
Abnormal proliferation of normal cells, caused by excessive hormonal stimulation, or the effect of growth factors on target cells
Hormonal hyperplasia
is also a physiologic response resulting from hormonal stimulation. This type of hyperplasia occurs mainly in estrogen-dependent organs such as the uterus and breast.
Hypoxia
the inadequate supply of oxygen to the tissue despite adequate perfusion of the tissue by blood. Inadequate oxygen supply will impair aerobic cellular respiration, interfering with energy (ATP) production in the cell. Anaerobic cellular respiration will occur, leading to a decrease in pH and further metabolic impairment. Hypoxia may be caused by:
Reduction of oxygen content of inspired air
Decrease in hemoglobin available for oxygen binding
Cardiovascular and/or respiratory disease
Pyropoptosis
Differs from apoptosis in that pyroptosis results in the lysis or dissolution of the cell, releasing destructive lysosomal enzymes into the tissue, which cause inflammation (swelling, redness, and pain) as well as damage to nearby cells and reduced function.
Liquefaction necrosis
Occurs when the necrotic material becomes softened and then liquefied under the influence of certain cell enzymes.
Coagulation necrosis
results from the denaturation of proteins, usually following hypoxic injury caused by ischemia (i.e., myocardial infarction). The cells retain some form for a period of time after death.
Fat necrosis
s a condition in which neutral fats of adipose (fat) cells are broken down into fatty acids by infectious material or by enzymes.
Caseous necrosis
is a form of coagulation necrosis in which a thick, yellowish, “cheesy” substance forms (as is found in cases of tuberculosis).
Explain how the condition of hyperplasia may eventually progress to neoplasia (cancer).
Hyperplasia involves the rapid increase in cell number, usually resulting in a larger cell mass. In the case of pathologic hyperplasia the increase is abnormal and could be a result of hormonal stimulation or effect on growth factors. This could in some cases lead to dysplasia in which the shape and structure of the cells also become abnormal. If the uncontrolled growth of abnormal cells continues, a cancer may develop.
Explain why the formation of necrotic tissue from a microbial infection would not be attributed to the process of apoptosis.
Apoptosis involves cell death caused by normal processes—it is often called programmed cell death. There need not be any external factors involved as the cell’s death is determined by its genes.
