patho chapter 1

Pathology

study of diseases that can cause abnormalities in the structure or function of various organ systems

Disease

the pattern of the body's response to some form of injury that causes deviation from or variation of normal conditions

hemi-

half

cyano-

blue

bi-

two

lipo-

fat

chondro-

cartilage

-clast

destroyer

Why is an understanding of pathology important for radiographers?

-adjustment in patient position

-change in routine projections

-alteration of the density of anatomical structures

(alteration of technical factors)

Signs are

measurable

symptoms are

subjective

Signs

measurable or objective manifestations

Symptoms

feelings that the patient describes- subjective manifestations

Asymptomatic

without subjective or objective manifestations

Diagnosis

identification of disease process

Etiology

study of the cause of the disease process

Idiopathic

underlying cause is unknown

Prognosis

probable patient outcome

Syndrome

linked combination of signs and symptoms

Latrogenic

disease caused by physician or treatment

Nosocomial infections

contracted from the acute care facility

Community-acquired infections

contracted in a public setting outside of the acute care facility

Inflamation

the initial response of body tissues to local injury

Five clinical signs of inflammation

Rubor (redness)

Calor (heat)

Tumor (swelling)

Dolor (pain)

Loss of function

1st event that occurs in Inflammatory Response

alterations in blood flow and vascular permeability

2nd event that occurs in Inflammatory Response

Migration of circulating white blood cells to the interstitium of the injured tissue

3rd event that occurs in Inflammatory Response

Phagocytosis and enzymatic digestion of dead cells and tissue elements

4th event that occurs in Inflammatory Response

Repair of injury by regeneration of normal parenchymal cells or proliferation of granulation tissue and eventual scar formation

Permeable membrane

allows fluids/cells to pass from one tissue to another tissue or location

Granulation tissue

Fibrous scar replaces destroyed tissue (ex- heart muscle)

Pyogenic bacteria

Thick, yellow fluid called pus (dead white cells)

Abcess

localized, usually encapsulated, collection of fluid- beneth the skin

Bacteremia

Potential involvement of other organs and tissues in the body by organisms invading the blood vessels

Edema

the accumulation of abnormal amounts of fluid in the intercellular tissue spaces or body cavities

Anasarca

Generalized edema occurs with pronounced swelling of subcutaneous tissues throughout the body

Elephantiasis

Localized lymphatic obstruction resulting in localized edema

Ischemia

an inadequate blood supply to an organ or part of the body, especially the heart muscles.

what can cause Ischemia

-narrowing of an artery, as in atherosclerosis

-thrombotic occlusion

-embolic occlusion

Gangrene

tissue necrosis caused by loss of blood supply

Infarction

localized area of ischemic necrosis within a tissue or organ

Hemorrhage

the rupture of a blood vessel that allows blood to escape externally or internally, within surrounding tissues or a cavity

Petechiae

small, pinpoint hemorrhages (usually less than 2 mm in diameter)

Purpura

the appearance of multiple purple discolorations on the skin caused by bleeding underneath the skin (usually 2-10 mm in diameter)

Ecchymosis

type of hemorrhage that is more than 10 mm in diameter

Hematoma

accumulation of blood trapped within body tissues

Atherosclerosis

narrowing of an artery

Hypotension

Alterations of cell growth happens when

there is a change in the number and size of cells, their differentiation, and their arrangement

Neoplasia

an abnormal proliferation of cells that are no longer controlled by the factors that govern the growth of normal cells

Atrophy

reduction in the size or number of cells

Hypertrophy

Increase in the size of the cells of a tissue or organ in response to a demand for increased function

Hyperplasia

increase in the number of cells

Dysplasia

loss of uniformity of individual cells in a tissue or organ

Oncology

study of neoplasms (tumors)

Benign

growth which closely resembles its cells of origin in structure and function

Malignant

Neoplastic growth that invades and destroys adjacent structures

Metastasize

malignant neoplasms travel to distant sites

Carcinoma

malignant neoplasm of epithelial cell origin

Anaplastic

Undifferentiated cell growth - without form (bizarre)

Sarcoma

highly malignant tumor originating from connective tissue

Lymphatic spread

major route of carcinoma to metastasize

Hematogenous spread

malignant tumors that have invaded the circulatory system and travel as neoplastic emboli

grading

assessment of aggressiveness or degree of malignancy

Staging

1) extensiveness of tumor at the primary site

2) presence or absence of metastases to lymph nodes and distant organs

Epidemiology

study of determinants of disease events in given populations

Morbidity

rate that an illness or abnormality occurs

mortality

Reflects the number of deaths by disease per population

Hereditary diseases results from

an abnormality in the DNA

Hereditary process

genetic information contained in the nucleus of each cell passed to the next generation

Autosomes

Forty-four chromosomes other than X and Y

Dominant genes

Always produce an effect

Recessive genes

manifest themselves when a person is homozygous for the trait

Mutations

alterations in the DNA structures that may become permanent hereditary changes

Three types of immune reactions

anaphylactic, cytotoxic reaction, and delayed

Antigen

Foreign substance that triggers an immune response

Antibody

immunoglobulin responding to the antigen; make harmless

Immune

Protected against antigens; antibodies binding with antigens to make them harmless

Active immunity

Forming antibodies to counteract an antigen by way of vaccine or toxoid

Vaccine

Contact with dead or deactivated microorganisms to form antibodies

Toxoid

Treated toxin with antigenic power to produce immunity by creating antibodies

Anaphylactic reaction

Hypersensitive reaction resulting in a histamine release

Standard precautions

Protection utilized when delivering healthcare services for any person

Personal Protective Equipment

PPE- gowns, masks, gloves, shoe covers, and eye protection used to prevent transmission of potential infectious agents

Transmission-based precautions

Additional protective equipment to prevent the spread of highly infectious pathogens through contact, droplet, or airborne transmission

Airborne

patient has known suspected infection with pathogens transmitted by the airborne route

Droplet

patient has known or suspected infection with pathogens transmitted by respiratory droplets

Contact

patient has known or suspected infection that represents risk for contact transmission

Enteric

patient has known or suspected infection of the gastrointestinal track