Module 1: intro to pathophysiology

pathophysiology

The study of functional or physiological changes in the body that result

from disease processes.

disease

A deviation from normal state of health or from homeostasis, marked by

specific signs and symptoms.

homeostasis

The maintenance of a relatively stable internal environment in the body.

examples of maintaining homeostasis

Blood pressure, body temperature, fluid balance

etiology

The cause of a disease (e.g., congenital defects, inherited disorders,

microorganisms, immune dysfunctions, trauma, toxins, nutritional deficits).

Idiopathic

when the cause of the disease is unknown 

Iatrogenic

a treatment, procedure, or error may cause the disease (side effect)

Ex. bone marrow damage caused by a prescribed drug

Ex. chemo and radiation can cause serious complications 

diagnosis

The identification of a specific disease through evaluation of signs,

symptoms, labs, imaging, and other tools.

Prevention

the known causes of and factors predisposing to specific diseases are being used in the development of more effective preventive programs

Primary Prevention

protect healthy people from developing a disease or experiencing an injury in the first place 

• Education about nutrition, exercise, drugs, alcohol

• Vaccines 

• Regular exams and screenings (ex. mammogram)  

Secondary Prevention

interventions happen after an illness or serious risk factors have already been diagnosed - goal is to halt or slow the progress of disease in its earliest stages

• Telling people to take daily, low dose aspirin to prevent a first or second heart attack or stroke

• Regular exams and screening tests in people with known risk factors for illness 

Tertiary Prevention

focuses on helping people manage complicated long-term health problems such as diabetes, cancer, a chronic musculoskeletal pain - goals include preventing further physical deterioration and maximizing quality of life

• Cardiac or stroke rehab programs

• Chronic pain management programs 

• Patient support groups 

Predisposing factors

the tendencies that promote development of a disease in an individual 

• Indicates a high risk for the disease but not certain development 

• May include age, gender, inherited factors, occupational exposure, certain dietary practices

Pathogenesis

refers to the development of the disease or the sequence of events involved in the tissue changes related to the specific disease process 

Acute disease

short-term illness that develops quickly with marked signs such as high fever or severe pain (Ex. acute appendicitis) 

Chronic disease

long-term  - often a milder condition that develops gradually but persists for a long time and usually causes more permanent tissue damage (Ex. rheumatoid arthritis) 

Latent stage

no clinical signs are evident, characterizes some diseases (incubation period - time between exposure to the microorganism and the onset of signs or symptoms) - Ex. HIV, TB

Signs

objective indicators of disease that are obvious to someone other than the affected individual 

• Ex. fever, rash, BP

Symptoms

subjective feelings 

• Ex. pain, nausea, fatigue

Syndrome

collection of signs and symptoms often affecting more than one organ, that usually occur together in response to a certain condition 

Remission

a period or condition in which the manifestations of the disease subside, either permanently or temporarily

• Ex. Rheumatoid arthritis, cancer

Exacerbation

worsening in the severity of the disease or in its signs and symptoms 

• Ex. asthma

Precipitating factor

condition that triggers an acute episode, such as a seizure in an individual with a seizure disorder 

Sequelae

potential unwanted outcomes of the primary condition, such as paralysis following recovery from a stroke 

Prognosis

defines the probability or likelihood for recovery or other outcomes 

Incidence

the incidence of a disease indicates the number of new cases in a given population noted within a stated time period. A significant increase or decrease in incidence of a specific disease may be analyzed to determine the responsible factors 

Prevalence

refers to the number of new and old or existing cases within a specific population and time period

Epidemic

occur when there are a higher than expected number of cases of an infectious disease within a given area, whereas pandemics involve higher number of cases in many regions of the globe 

Pandemic

involve higher numbers of cases in many regions of the globe 

Apoptosis

programmed cell death : normal occurrence in the body which may increase when cell development is abnormal, cell numbers are excessive or cells are injured or age 

Necrosis

refers the the death of one or more cells or a portion of issue or organ as a result of irreversible damage and not a programmed cellular event 

pyroptosis

intracellular infection, cell explodes, releases enzymes and cytokines, inflammation

5 common causes of cell damage: 

1. Ischemia: deceased supply of oxygenated blood to a tissue or organ, owing to circulatory obstruction 

2. Physical agents, excessive heat or cold, or radiation exposure 

3. Mechanical damage such as pressure of tearing of tissue

4. Chemical toxins 

5. Microorganisms such as bacteria, viruses, and parasites 

6. Abnormal metabolites accumulating in cells  

7. Nutritional deficits 

Hypoxia

reduced oxygen in the tissue 

Atrophy

decrease in the size of cells, resulting in a  reduced tissue mass

Hypertrophy

increase in the size of individual cells, resulting in enlarged tissue mass 

Hyperplasia

an increased number of cells resulting in an enlarged tissue mass 

Dysplasia

the term applied to tissue in which the cells vary in size and shape, large nuclei are frequently present, and at the rate of mitosis is increased 

Anaplasia

refers to cells that are undifferentiated with variable nuclear and cell structures and numerous mitotic figures 

Metaplasia

occurs when one mature cell type is replaced by a mature cell type 

Neoplasia

means “new growth” and neoplasm is commonly caused a tumor 

Necrosis

the term used when a group of cells die and cause further damage because of cellular disintegration 

Liquefaction necrosis

1. refers to the process by which dead cells liquefy under the influence of certain cell enzymes 

Coagulative necrosis

1. occurs when the cell proteins are altered or denatured and cells retain some form for a time after death - process usually occurs during an MI 

Fat necrosis

1. occurs when fatty tissue is broken down into fatty acids in the presence of infection of certain enzymes - these compounds may increase inflammation 

Caseous necrosis

1. form of coagulation necrosis in a thick, yellowish, “cheesy” substance forms 

Gangrene

refers to an area of necrotic tissue, usually associated with a lack or loss of blood supply that is followed by invasion of bacteria