RADPATHO 2 (copy)

PATHOLOGY

The study of diseases that can cause abnormalities in the structure or function of various organ system.

DISEASE

• Pattern of the body’s response to some form of injury that causes variation of normal conditions

• Disturbance in the function or structure of the human body

• Congenital and Hereditary

• Inflammatory

• Degenerative

• Metabolic process

• Traumatic

• Neoplastic

Pathologic process can be defined as following:

ETIOLOGY

study of the cause of a disease:

• Viruses

• Bacteria

• Trauma

• Heat

• Chemical agents

• Poor nutrition

NOSOCOMIAL

diseases caused by physicians or their treatment

COMMUNITY ACQUIRED

infections that develop outside the healthcare facility

IDIOPATHIC

underlying cause is unknown

ACUTE

• quick onset and last for a short period e.g. Pneumonia

• May be followed by lasting effects –sequelae

• e.g. Stroke, or cerebrovascular accident, resulting in long-term neurologic deficits

• diseases may manifest more slowly and Last for a very long time

• e.g. Multiple sclerosis, diabetes mellitus experiencing hypoglycemia or hyperglycemia

DIAGNOSIS

is the identification of a disease an individual is believed to have

PROGNOSIS

- predicted course and outcome of the disease

MORPHOLOGY

The structure of cells or tissue

EPIDEMIOLOGY

is the investigation of disease in large groups

INFLAMMATION

Initial response of body tissues to local injury

Process:

• Dilation of arterioles, capillaries, and

• venules (hyperemia)

• Heat and redness: Venules and capillaries become abnormally permeable (allowing exudate in the surrounding tissue)

• Swelling produces pressure on sensitive nerve endings (Pain)

• Fever – common in inflammatory conditions

• Rubor (redness)

• Calor (heat)

• Tumor (Swelling)

• Dolor (pain)

• Loss of function

Clinical signs of acute inflammation

1. Alteration in blood flow and vascular permeability

2. Mitigation of circulating WBC to the interstitium of the injured tissue

3. Phagocytosis and enzymatic digestion of dead cells and tissue elements

4. Repair of injury by generation of normal parenchymal cells of proliferation of granulation and eventual scar formation

Events that occur in Inflammatory response

EDEMA

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

LOCALIZED

inflammatory reaction

ANASARCA

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

• Congestive heart failure, Liver Cirrhosis, Renal disease

ISCHEMIA

Refers to an interference with the blood supply to an organ or part of an organ.

May be caused by:

• narrowing of arterial structures (atherosclerosis)

• thrombotic or embolic occlusion

• Ganglion cells and myocardial muscles cells undergo irreversible damage if deprived of their blood supply for 3 to 5 mins.

• Commonly seen in Anemic or cyanotic patients.

INFARCT

Localized area of ischemic necrosis within a tissue or organ produced by occlusion of either its arterial supply or its venous drainage.

NECROSIS

tissue death that may be caused by lack of blood supply

GANGRENE

condition that results from death of tissue due to lack of blood supply

HEMORRHAGE

• Rupture of blood vessels

• Trauma, atherosclerosis, an inflammatory or neoplastic erosion of vessels

HEMATOMA

trapped blood within the body tissues

PETECHIAE

minimal hemorrhages into the skin, mucous membranes, or serosal surfaces

PURPURA

Slightly larger hemorrhages

ECCHYMOSIS

large (greater than 1 to 2 cm) subcutaneuos hematoma

• Atrophy

• Hypoplasia

• Aplasia

• Hypertrophy

• Hyperplasia

• Metaplasia

• Dysplasia

ALTERATIONS OF CELL GROWTH

Atrophy

reduction in the size or number of cells in an organ or tissue

Hypoplasia

underdevelopment

Aplasia

failure to develop

Hypertrophy

increase in the size of cells in an organ or tissue

Hyperplasia

increased number of cells

Metaplasia

conversion of one cell type into another cell type that is not normal for that tissue

Dysplasia

loss of uniformity of individual cells and their architectural orientation

NEOPLASIA

• - Latin words meaning “New Growth” (Tumor)

• - Abnormal proliferation of cells

• - Can be Benign or Malignant

• - Cells acts as parasites, competing with normal cells and tissues for their metabolic needs

CASHEXIA

tumor cells flourish; patient becomes weak and emaciated

ONCOLOGY

• Study of neoplasms.

• -Greek words “oncos”, meaning tumor.

Basic components of tumors

1. The parenchyma (organ or tissue), made up of proliferating neoplastic cells

Determines how the tumor behaves

2. The supporting stroma (tissue), made up of connective tissue, blood vessels, and possibly lymphatic vessels

Benign tumors

• Resemble the cells of origin in structure and function

• Remain localized

• Can be surgically removed

• e.g. pituitary, islets of Langerhans, brain, spinal cord, trachea, esophagus.

• -oma - Fibroma, Chondroma, Adenoma,

  Cystadenoma, Lipoma, Myoma, Angioma,

  Papilloma (polyp)

Malignant tumors (Cancer)

• Cancer – latin word karnikos meaning “crab” (has fingerlike projections)

• Invades and destroys adjacent structures and spread to distant sites (metastasize)

• Poorly differentiated (may be impossible to determine which organ they originate)

• Are called carcinomas

• Affects epithelial tissues, skin, and mucous

• membranes lining body cavities

• Adenocarcinoma, Basal cell carcinoma, Squamous Cell Carcinoma

Sarcoma

• Highly malignant tumors arising from connective tissues such as bone, muscle, and cartilage

• Less common than carcinoma, but tend to spread more rapidly

Carcinogens

– substance that promotes carcinogenesis; formation of cancer

Chemical carcinogens

Air and water pollution, cigarette smoke, asbestos, food, cosmetics, and plastic Excessive exposure to sunlight

metastasis

The spread of malignant cancer cells resulting in a secondary tumor distant from the primary lesion is termed_____

1. Seeding within the body

2. Lymphatic spread

3. Hematogenous spread

Malignant neoplasms disseminate to distant sites by one of three ways

Seeding (diffuse spread)

• Cancerous cells travel to a distant site or distant organ system

• Neoplasms invade body cavities

• GIT to the peritoneum to distant sites

Lymphatic spread

• Major metastatic route of carcinomas (Lung and breast)

• Depends on the site and natural lymphatic drainage (sentinel node)

Hematogenous spread

• Invasion of the circulatory system

• Complex process involving several steps

• Invade and penetrate blood vessels, travel as neoplastic emboli, can be trapped in small vessels

• Certain types of cancer appear more often as metastases from other areas rather than originating in a given organ

Staging of Malignant Tumor

• Extensiveness of a tumor at its primary site

• Presence or absence of metastases to lymph nodes and distant organs

• Determines the most appropriate therapy

Malignant tumor

Localized tumor – surgically removed

Hodgkin’s disease – radiation therapy

Prostate cancer – hormonal therapy

Chemotherapy

T

• The ___ refers to the size and extent of the main tumor. The main tumor is usually called the primary tumor.

• it can be 1, 2, 3 or 4, with 1 being small and 4 large

N

• The ___ refers to the number of nearby lymph nodes that have cancer.

• it can be between 0 (no lymph nodes containing cancer cells) and 3 (lots of lymph nodes containing cancer cells)

M

• The ___ refers to whether the cancer has metastasized. This means that the cancer has spread from the primary tumor to other parts of the body.

• it can either be 0 (the cancer hasn't spread) or 1 (the cancer has spread)

TNM SYSTEM

• In situ—Abnormal cells are present but have not spread to nearby tissue.

• Localized—Cancer is limited to the place where it started, with no sign that it has spread.

• Regional—Cancer has spread to nearby lymph nodes, tissues, or organs.

• Distant—Cancer has spread to distant parts of the body.

• Unknown—There is not enough information to figure out the stage.

Grading of Malignant Tumor

• Assesses aggressiveness or degree of malignancy

• Indicates its biological behaviour

• Allows prediction of its responsiveness to therapeutic agents

• How abnormal the tumor cells and the tumor tissue look under a microscope

Grade 1

The cancer cells look very similar to normal cells and are growing slowly (Well differentiated) (low grade)

Grade 2

• The cells look unlike normal cells and are growing more quickly than normal

• Moderately differentiated (intermediate grade

Grade 3

The cancer cells look very abnormal and are growing quickly Poorly differentiated (high grade)

Grade 4

Tumors tend to grow rapidly and spread faster (Undifferentiated) (high grade)

GX means that the grade can't be assessed. It is also called undetermined grade.

Hereditary Diseases

• Passed from one generation to the next

• Reflects abnormality in the DNA

• Enzyme deficiency

• Albinism (absence of pigmentation), Phenylketonuria (build up of phenylalanine)

• Globin molecule defect

• Sickle cell disease and thalassemia (abnormal hemoglobin), Glucose-6-Phosphate Dehydrogenase Deficiency (adverse reaction to drugs)

• Mutations – alterations in DNA structure -May become permanent if they affect gonadal cells

Autosomal Dominant disorders

• Transmitted from one generation to the next (Hetrozygous)

• Achondroplasia (dwarfism), Neurofibromatosis (tumors of the nervous system), Marfan’s syndrome (disorder of the connective tissue), Familial Hypercholesterolemia (high levels of LDL in the blood)

Autosomal Recessive disorders

• Homozygous for the defective gene

• Close intermarriages

• Phenylketonuria, Cystic fibrosis (affects cells that produce mucus, sweat, and digestive juices), Galactosemia, Glycogen and Lipid storage diseases, Tay-Sachs disease (absence of a vital enzyme called hexosaminidase-A (Hex-A)), Sickle cell anemia

Acquired Immunodeficiency Syndrome

• Commonly affects young homosexual men, IV drug abusers, Hemophiliacs, and in recipients of transfusions

• Characterized by a profound and sustained impairment of cellular immunity that results in recurrent or sequectial oppurtunistic infections and particularly aggressive form of Kaposi’s sarcoma

• Affects the skin and causes an ulcerated hemorrhagic dermatitis

• Small bowel metastasis can produce reddish or bluish red nodules

• Attributable to infection with retroviruses (HIV)

• Pulmonary infections are common in patients with AIDS

• Pneumocystis Carinii Pneumonia (usually fatal is untreated)

• GI manifestations Rectum and colon, Shigellosis, Amebiasis, Candidiasus, and Giardiasis