Pathology For Radiology Technologist I

Flashcards related to Pathology for Radiology Technologist I lecture notes.

Pathology

The science that deals with the study of diseases.

Gross Features (Macroscopic)

Change in size, color, and consistency of the diseased organ.

Microscopic Features

Cellular and extracellular changes, such as the detection of malignant cells.

Biopsy

Examination of a tissue specimen.

Autopsy

Examination of tissue obtained from dead bodies.

Frozen Section Examination

Used for rapid diagnosis during surgery.

Cytology

Examination of body fluids or smears to detect any abnormal cells, such as malignant and inflammatory cells.

Purpose of Fixation

To prevent autolysis, bacterial decomposition, and putrefaction.

Lesions

The changes in tissues and cells produced by diseases.

Etiology

Factors and causes of disease.

Pathogenesis

Mechanism of disease.

Complication

Secondary effect of disease.

Prognosis

The course and fate of disease.

Cell Injury

Adaptive capability of cells to stimulus are exceeded or no adaptive response is possible.

Ischemia

Obstruction of arterial blood flow

Infectious agents

Viruses, bacteria, fungi, protozoa and metazoa all cause diseases.

Physical agents

Extremes of temperature, radiation, and electric shock.

Immunologic reactions

Autoimmune reactions against one's own tissues.

Reversible injury (Degeneration)

caused by mild injury, resulting in intracellular accumulation of water, fat, Protein, cholesterol, glycogen, iron, calcium or pigments.

Necrosis

Irreversible injury, resulting in death of groups of cells in living tissue. It is accompanied by acute inflammatory reaction

Apoptosis

death of individual cells surrounded by viable cells

Cellular Swelling

Is the first manifestation of almost all forms of injury to cells, it occurs due to incapability of cells to maintain ionic & fluid homeostasis.

Steatosis (fatty change)

intracellular accumulation of triglycerides within parenchymal cells

Point of no return

Irreversible mitochondrial damage and disturbances in cell membrane function

Necrosis

Irreversible injury, resulting in death of groups of cells

Apoptosis

Death of individual cells surrounded by viable cells with activation of an internally suicide program

Hyaline Degeneration

Alteration within cells or in the extracellular space that gives a homogeneous glassy pink appearance in routine histologic sections stained with hematoxylin and eosin

Russel bodies

This is hyaline change in plasma cells in chronic inflammation due to distension with immunoglobulins

Neurofibrillary tangle

Aggregation of proteins that are present in the brain of Alzheimer disease

Mucoid Degeneration

Accumulation of excessive amount of mucin in unusual location

Xanthomas and xanthelasma

Clusters of foam cells in tumor-like masses

Intracellular Accumulation

Metabolic derangements in cells can lead to the intracellular accumulation of abnormal amounts of various substances that remains either transiently or permanently

Amyloidosis

Extracellular accumulation of abnormal folded protein →→cell death

Lipofuscin pigment

An insoluble pigment, also known as lipochrome or wear-and tear pigment (aging pigment).

Melanin

Most common ; brown black pigment normally present in hair , skin, choroid of eye, meninges and adrenal medulla.

Leukoderma

Patchy skin hypopigmentation. May be congenital or acquired as in leprosy.

Hemosiderin (iron)

Systemic overload of iron.

Hemosiderosis

When accumulation of hemosiderin is primarily within tissue macrophages & is not associated with tissue damage

Hemochromatosis

When there is more extensive accumulation of hemosiderin, often within parenchymal cells, which leads to tissue damage, scarring & organ dysfunction

Bilirubin

A yellowish pigment, mainly produced during the degradation of hemoglobin. Excess accumulation of bilirubin causes yellowish discoloration of the sclerae, mucosae, & internal organs

Anthracosis

inhalation of carbon particles engulfed by macrophages. This pigment blacken the tissues of the lungs e.g. cigarette smoking, , air pollutant of urban life. coal dust in coal workers

Pathological Calcification

Abnormal intracellular or extracellular depositions of calcium salts.

Dystrophic Calcification

Occurs locally in dying tissue.

Metastatic Calcification

Calcification of normal tissues due to hypercalcemia

Inflammation

A local protective response of living vascularized tissues to kill and remove injurious agents& prepare for repair.

Add the suffix ―itis‖ to organ name

Examples:- - Tonslitis, Rhinitis,

Transient Vasoconstriction

A neural mechanism that lasts for few seconds or minutes followed by vasodilatation

Permanent Vasodilatation

result of redness and hotness in inflamed area

Increase hydrostatic pressure

lead to transudation of fluid into extracellular space

exudate

The protein-rich fluid which is now found in the extravascular space

margination

When blood slowing occurs, some leukocytes (mainly neutrophils and monocytes) fall out of the central column and begin to line the endothelium

pavementing

Adhesion of the marginating leukocytes to the endothelial surface occurs, aided by complementary receptors on the surfaces of leukocytes and endothelial cells

Emigration of leucocytes

Insertion of leukocyte pseudopodia into the junction between the endothelial cells → escape of leukocytes into the extravascular space

Chemotaxis

It is the directed movement of emigrating leukocytes to the site of injury.

Phagocytosis

the process by which the phagocytic cells recognize then engulf abnormal particles such as bacteria, dead cells, fibrin and articles to be phagocytized

opsonization

bacteria are coated by an opsonin which is an immunoglobulin or complement factor

Degranulation

performed granule-stored products are discharged or secreted into phagosomes

Chemical mediators of acute inflammation

Any substances that secreted and activated to help inflammatory process acts on blood vessels, inflammatory cells or other cells

Fate of acute inflammation - Spread

Spread (Septicemia , toxemia, lymphangitis, lymphadenitis Thrombophlebitis)

Fibrosis (Scarring): a.

a. After extensive tissue destruction. b. When the inflammatory injury involves tissues that are incapable of regeneration. c. When there is abundant fibrin exudation.

Fibrosis (Scarring): b.

a. After extensive tissue destruction. b. When the inflammatory injury involves tissues that are incapable of regeneration. c. When there is abundant fibrin exudation.

Fibrosis (Scarring): c.

a. After extensive tissue destruction. b. When the inflammatory injury involves tissues that are incapable of regeneration. c. When there is abundant fibrin exudation.

Another name for Abscess Formation Progression to Chronic Inflammation

thrombophlebitis

Suppurative/ Purulent acute inflammation Characteristic

pus is purulent thick, turbid yellowish inflammatory exudate

Serous inflammation:

Examples:-  Skin blisters due to skin burns.  Inflammation of serous membranes (pleura, pericardium and peritoneum)

Fibrinous inflammation

Characterized by: - an inflammatory exudate rich in fibrin, with poor fluid. Examples:- Lobar pneumonia or inflammation of serous membranes

Catarrhal inflammation

A mild form of acute inflammation of mucous membranes with excess mucus secretions

Pseudomembranous /Membranous inflammation

Occur in mucous membrane with dirty grayish false membrane forming on surface e.g. toxins of diphteria and irritant gases

Allergic inflammation

characterized by: - the presence of excessive serous fluid and many eosinophils in the inflammatory exudate. Examples:- Allergic rhinitis or Allergic conjunctivitis

Chronic Inflammation

Inflammation of prolonged duration weeks to years, in which inflammation, tissue destruction occur in same time

Granulomas/ granulomatous inflammation

A special form of chronic inflammation characterized by nodular collections of many macrophages with mixture of lymphocytes, plasma cells, giant cells.

Chronic Specific Inflammations

Show microscopic features of chronic inflammation with additional features specific to its type.

Granulomas/ granulomatous inflammation Characteristic

Macrophages have an important role

Healing by regeneration

Proliferation of cells to replace the damaged components by same type of cells and return to a normal state

Healing By Fibrosis

Replace the damaged components by scar formation due to deposition of connective (fibrous) tissue

Fibrogenesis

Migration and proliferation of fibroblasts to the site of damage by action of growth factors include PDGF, FGF, TGF – beta & Cytokins e.g. TNF, IL-1

Angiogenesis

Formation of new blood vessels by action of growth factors include VEGF, PDGF, FGF &TGF – beta

First intention healing (primary union)

Small wounds that easily close edges with epithelial regeneration predominating over fibrosis

Second intention healing (Second union)

Larger wounds that have large gap, large amount of granulation tissue & fibrosis

Bone Healing

The repair of a bone fracture

Routes of infection

Inhalation, ingestion or local contact with skin or mucous membranes, blood or blood product transfusion

Mycobacterium tuberculosis

Rod shaped Acid fast bacilli that cause tuberculosis

Primary tuberculosis

The first time TB bacilli enter the body

Organism reach organ again thru endogenous or exogenous routes

Patient has acquired secondary tuberculosis

Ghon`s focus in the Primary Pulmonary Tuberculosis

Small yellow subpleural granuloma in mid lung field

Caseating granuloma

Central caseous necrosis surrounded by epitheloid cells , Langhan‘s giant cells& lymphocytes in the granulomas of tuberculosis

Leprosy

Hansen disease, is a chronic, slowly progressive, destructive infective granulomatous disease involving peripheral nerves, skin, and mucous membranes, caused by Mycobacterium leprae

Leprosy

Chronic, slowly progressive, destructive infective granulomatous disease involving peripheral nerves, skin, and mucous membranes, caused by Mycobacterium leprae

Tuberculoid leprosy

In which lesion of tuberculosis lack caseous necrosis, occurs in patients with high resistance and is the mildest form of Leprosy

Lepromatous leprosy

Exhibits multiple tumor like lesions of the skin, eyes, testes, nerves, lymph nodes, and spleen caused by nodular infiltrates of foamy macrophages loaded with bacilli

Actinomycosis

Granulomatous disease caused by gram-positive anaerobic bacteria Actinomyces Israeli, normally present in the oral cavity and intestine as harmless commensals

Cervicofacial Actinomycosis

In which bacterial invasion of buccal mucosa may sometimes follow dental extraction and blood spread causes pulmonary

Gross pathology due to

C/b Multiple abscesses with indurated fibrotic walls in Pulmonary Actinomycosis

Tuberculosis

Chronic infectious granulomatus inflammation

Infection - causes

Bacterial, viral, protozoal, or fungal

2 Types of Exogenous

Bacterial as E.coli and Endotoxins

Define INFLAMMATION

Local protective response of living vascularized tissue to irritant

Microbial infections

Bacteria and their toxins, viruses, fungi, and parasites

Physical irritants

Burns, excess cold, ultraviolet light, irradiation

Mechanical irritants?

Trauma