Week 1: Causes of Disease

Question 1

Pathology

Answer 1

Study of disease. Study of the structural and functional changes in cells, tissues, and organs that are caused by disease.

Question 2

Clinical pathology

Answer 2

The study of the cause, mechanisms, and effects of the disease.

Question 3

Experimental pathology

Answer 3

Experimental studies on tissues, cell cultures, or animal models.

Question 4

Cytopathology

Answer 4

Examination of isolated cells.

Question 5

Histopathology

Answer 5

Examination of tissues.

Question 6

Surgical pathology

Answer 6

Histologically examining surgical tissue specimens from biopsies to determine the nature of the disease.

Question 7

Gross pathology

Answer 7

Taking samples from tissue and examining them with light microscopy and electron microscopy at cellular and molecular levels.

Question 8

Special stains

Answer 8

Special stains identify elastic tissues, veins, and abnormalities.

Question 9

Immunohistochemistry

Answer 9

Uses primary antibodies that recognize antigen of interest (i.e. CDX2). A secondary antibody has a linker system that recognizes the primary antibody.

Brown = positive

Question 10

Molecular testing

Answer 10

Identifies the genetic characteristics of a disease (i.e. genes involved in tumours)

Question 11

What is a disease, and when does it occur?

Answer 11

It is any deviation from the normal function/structure of tissues, organs, or systems. Disease occurs when cells fail to adapt to injury, or when the adaptation is harmful.

Question 12

Injury

Answer 12

Due to disturbances from physical/chemical agents.

Reversible: cell/tissue survives or adapts

Irreversible: leads to death or degeneration of the cell

Question 13

Inflammation

Answer 13

Common response to disease following injury or infection. Some diseases are primarily inflammatory (e.g. tonsilitis).

Chronic inflammatory response occurs in allergic reactions or viral/parasitic ones.

Question 14

Infection

Answer 14

One of the most common forms of disease. Usually produces mild to moderate symptoms. Infectious organisms (i.e. viruses, bacteria, parasites) can produce more serious illness in immunocompromised individuals.

The extent of cellular pathology and disease depends on factors of both the attacking organism and host’s responses.

Question 15

Immunological Reaction

Answer 15

Immune response is normally protective, but in some circumstances the reaction may become

1. Excessive (e.g. hypersensitive to allergens - anaphylactic shock)
2. May act against the body’s own cells (e.g. autoimmune disease - thyroiditis, myasthenia gravis),
3. May be absent or depressed (e.g. severe combined immunodeficiency disease, immunosuppressive therapy).

Question 16

Neoplasia

Answer 16

Autonomous proliferation of cells, usually causing tumours or masses. Can be benign or malignant.

Question 17

Metabolic or Endocrine disease

Answer 17

Disorders of enzymes, hormones, or secretory products (e.g. DM2). Some metabolic diseases are genetic (e.g. congenital adrenal hyperplasia)

Question 18

Nutritional disease

Answer 18

1. Deficiencies in proteins or calories due to insufficient supply; decreased transport, absorption, or utilization, or specific vitamin; or mineral deficiencies.
2. Excess calories/obesity increases risk of a number of conditions.

Question 19

Vascular disease

Answer 19

One of the most common causes death in developed countries. Abnormalities in blood vessels.

Narrowing of important blood vessels (atherosclerosis) underlies common causes of morbidity and mortality (heart attacks, strokes).

Question 20

Psychological factors of disease

Answer 20

Psychological stress may cause and affect disease processes and can lead to mental illness or worsen the existing somatic disease.

Also an important factor in disease caused by addiction

Question 21

Physical signs of disease

Answer 21

Objective evidence

EX Blood in stool

Question 22

Symptoms of disease

Answer 22

Subjective evidence of disease (what the patient tells you)

EX “I have stomach pain”

Question 23

Genetic insults and causes of disease

Answer 23

Includes single mutations to large alterations to chromosomes. May be congenital or acquired.

Inherited genetic causes are rare; it is more common to have sporadic mutations to DNA throughout life

Not all inherited genetic diseases manifest at birth; Huntington’s Chorea is not seen until adulthood

Not all congenital diseases are genetic; infections can result in heart defects, cataracts, microcephaly, etc)

Question 24

Environmental insults/causes of disease

Answer 24

Physical or chemical agents (i.e. drugs)
Iatrogenic (i.e. adverse event as a result of treatment)
Allergens
Personal/lifestyle habits (i.e diet, exercise, weight control, smoking)

Question 25

Iatrogenic disease

Answer 25

Diseases that are caused by medical therapy. Unintended injuries or complications resulting in death, disability, or prolonged hospital stays from health care management

Question 26

Etiology

Answer 26

Cause of a disease process.
Allow us to understand causes of disease to avoid/be educated about (i.e. hepatic cirrhosis can be caused by viruses, alcohol, storage disorders)

This may also include cause of death in autopsy context (i.e. head trauma caused by MVC)

Idiopathic disease = unknown etiology

Question 27

Complications and sequelae

Answer 27

Secondary consequences of disease or procedure (i.e. post-op infection)

Question 28

Morbidity

Answer 28

Illness that impairs well-being and normal function of patient (living with disease)

Question 29

Mortality

Answer 29

Death; differs within age groups (death from disease)

Question 30

Pathogenesis

Answer 30

Development of a given disease; the sequence of cellular events that take place from time of initial contact with the etiologic agent to the expression of the disease.

Mechanism/how the disease evolves

Question 31

Pathological and morphological manifestations

Answer 31

Pathological: Changes in structure and function of tissues, organs, and systems.

Morphologic: Changes are anatomic and microscopic; characteristic of disease

Question 32

Epidemiology

Answer 32

Study of disease in populations (i.e. causes, distributions, control). Considers health indicators, life expectancy, infant mortality.

Question 33

Incidence vs. prevalence

Answer 33

Incidence: number of new cases in the population over a time period

Prevalence: total number of cases (new and existing) in the population

Question 34

PDL1 Testing

Answer 34

PDL1 on cell membranes blocks tumour’s immune reaction.

Inhibitors can block PDL1, which stimulates immune system to attack

Cancers have a lot of PDL1 (so the tumor survives)