Pathology Unit 1 Test Review

Pathology

The study of disease

Disease

Any abnormal disturbance of the function o structure of the human body as a result of some type of injury

Pathogenesis

The sequence of events producing cellular changes that ultimately lead to observable changes known as manifestations

Manifestation

Observable changes resulting from cellular changes in the disease process

Symptom

Are subjective , and only the individual can identify these manifestations (headache)

Sign

Objective manifestation that is detected by the physician during examination (fever)

Syndrome

A group of signs and symptoms that characterizes a specific abnormal disturbance (respiratory distress syndrome in premature infants)

Etiology

The study of the cause of a disease

Nosocomial

One acquired from the environment

Hospital acquired

Staph infection

Iatrogenic

Adverse responses to medical treatment itself

(Collapsed lung from line placement)

Idiopathic

No causative factor an be identified

Acute

Quick onset and last for a short period of time (pneumonia)

Chronic

Manifest more slowly and last for a very long time

(Multiple sclerosis)

Sequelae

A condition that is caused by a previously acquired disease

(A stroke resulting in long-term neurological deficits)

Diagnosis

The name of a disease an individual is believed to have

(Identified of a disease)

Prognosis

The prediction of course and outcome for a given disease

Morphology

The structure of cells or tissue

Subtractive/Lytic/destructive

Lower Atomic number

Lower exposure techniques

Additive/Sclerotic

Higher atomic number

Higher exposure techniques

Epidemiology

the investigation of disease in large groups

Prevalence

refers to the number of cases of specific disease found in a given population

Incidence

refers to the number of new cases found in a given period

Epidemic

defined as the rapid, widespread occurrence of a disease in a large number of people in a given population

Pandemic

an epidemic affecting the majority of a population of a large region or an epidemic occurring at the same time in many different parts of the world

Mortality rate

the average number of deaths caused by a particular disease in a population

National Center for Health Statistics (NCHS)

Centers for Disease Control and Prevention (CDC)

Morbidity rate

The incidence in the population of illness sufficient to interfere with an individual’s normal daily routine

Genome

The entirety of an organism’s hereditary information, including both the genes and the noncoding sequences of DNA and RNA

Physical maps

used to determine the physical location of a particular gene on a specific chromosome

Genetic maps

used to assign the distance between genetic markers, that is, mapping or linking DNA fragments to a specific chromosome

useful in tracking the inheritance of traits and diseases that are transmitted from parent to child, as genetic markers that are in proximity increase the probability that the genes will be inherited together

Single-nucleotide polymorphisms (SNPs)

A DNA sequence variation occurring when a single nucleotide in the genome differs between members of a biologic species or paired chromosomes in an individual

Haplotype (hap map)

A combination of DNA sequences at adjacent locations on the chromosome that are transmitted together

Atrophy

a generalized decrease in cell size

Hypertrophy

generalized increase in cell size

Hyperplasia

an increase in the number of cells in a tissue as a result of excessive proliferation

Metaplasia

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

Dysplasia

abnormal changes occurring in mature cells

Congenital Disease

• Diseases present at birth and result from genetic or environmental factors

  • Estimated that 2% to 3% of all live births show one or more congenital diseases

  • Major category of congenital diseases caused by abnormalities in number and distribution of chromosomes

  • (Down syndrome)

Hereditary Disease

• Caused by developmental disorders genetically transmitted from either parent to child through abnormalities of individual genes in chromosomes

  • are derived from ancestors

  • may be dominant (transmitted by a single gene from either parent) or recessive (transmitted by both parents to an offspring)

  • (Hemophilia)

Inflammatory disease

Disease that results from the body’s reaction to a localized injurious agent

Infective Disease

Invasion by microorganisms such as viruses, bacteria, or fungi

Toxic Disease

Poisoning by biologic substances

Allergic Diseases

Overreaction of body’s own defenses

(Pneumonia)

Autoimmune Disordes

Disease in which antibodies form against and injure the patient’s own tissues, in contrast to the normal process in which antibodies form in response to foreign antigens

Autoantibodies

Antibody acting against its own tissue or organism

(Rheumatoid Arthisitis)

Inflammatory reaction

• Generalized pathologic process that is nonspecific to the agent causing the injury

  • Purpose is to localize the injurious agent and prepare for subsequent repair and healing of the injured tissues

  • Local and systemic effects

Capillary dilation

allow fluids and specifically leukocytes to infiltrate into the area of damage

Cellular necrosis

is common in acute inflammation

Phagocytosis

the ingestion of other cells or particles

the leukocytes serve to remove dead material through phagocytosis

Acute inflammation

Heat

• Redness of skin

• Swelling

• Pain

• Loss of function

• Elevated body temperature

Chronic inflammation

Damage caused by an injurious agent may not result in necrosis.

Longer duration of inflammation periods

Tissue regeneration

the process by which damaged tissues are replaced by new tissues that are essentially identical to those that have been lost

Debridement

removal of dead cells and materials

essential component of the healing process

may be accomplished both at the cellular level and through human intervention

Repair process

begins with the migration of adjacent cells into the injured area and replication of the cells via mitosis to fill the void in the tissue.

Remodeling

the last phase in the healing process, occurs in response to normal use of the tissue

Infection

an inflammatory process caused by a disease-causing organism

Virulence

Inflammation can occur without

the ease with which an organism can cause disease

Degenerative

• Disease caused by a deterioration of the body

  • May occur following traumatic injury, regardless
    of age

  • Process of aging

  • Factors affecting the rate of aging

    • Atherosclerosis

    • Osteoporosis

    • Osteoarthritis

Metabolic

• Disease caused by the disturbance of the normal physiologic function of the body

  • Endocrine disorders and disturbances of fluid and electrolyte imbalances

  • Endocrine disorders

    • Hypersecretion

    • Insufficient secretion

  • Fluid imbalance

    • Dehydration

  • Homeostasis

Traumatic

• Disease that may result from mechanical forces such as crushing or twisting of a body part or from the effects of ionizing radiation on the body

  • Fracture

  • Wound

  • Bruise/contusion

Neoplastic disease

• Disease that results in new, abnormal tissue growth

  • Benign neoplasm

  • Malignant neoplasm

  • Metastatic spread

    • Hematogenous spread

    • Lymphatic spread

    • Invasion

    • Seeding

  • Lesion

Cancer

general term often used to denote various types of malignant neoplasms

Carcinoma

A malignant growth comprised of epithelial cells that tend to invade surrounding tissues and give rise to metastases

Primary diagnostic modalities

computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), hybrid imaging using both CT/PET and CT/SPECT, radiography, and ultrasonography

Primary treatment modalities

radiation therapy in combination with surgery, chemotherapy, hormone or antihormone therapy, immunotherapy using biologic response modifiers such as interferons and interleukins, and targeted drug therapies

Palliative

Treatment designed to relieve pain without the goal of cure

Staging of cancer

TNM system emerged in 1950s and endorsed by AJCC

• T—Tumor size

• N—Node (lymph node involvement)

• M—Metastases

• Addition of numbers indicates the extent of malignancy and progressive increase in size or involvement of tumor (T0–T4)

  • Histopathologic type and grade

  • Scale of I–IV

  • Lymphatic or venous invasion

  • Residual tumor classification

  • Facilitates treatment planning, provides indication of prognosis, assists in evaluating results, facilitates information exchange, and allows categorization of malignancies

MRI

Magnetic resonance imaging (MRI) is an important modality used in imaging of skeletal pathology, particularly in providing soft tissue detail because of its superior contrast resolution and ability to image in multiple planes. It is considered the modality of choice for the detection and staging of soft tissue tumors involving the extremities.

Computed Tomography

Computed tomography (CT) is an important tool in skeletal imaging because the examination can be performed quickly and noninvasively, even in cases of trauma. CT can define the presence and extent of fractures or dislocations to assess abnormalities in joints and associated soft tissues, and to help diagnose spinal disorders

Nuclear Medicine

Nuclear medicine retains an advantage not offered by either MRI or CT in skeletal imaging: the ability to look at the entire body at one time in a convenient fashion. It provides decision making as to whether any pathology shown is an old injury or a new problem, with activity indicating that the bone involved is affected by some new process.

Osteogenesis imperfecta (OI) (brittle bone disease)

a serious but rather rare heritable or congenital disease affecting the connective tissue

• most commonly the result of an autosomal dominant defect

  • Classified I–VIII

  • Mutations in structural genes that encode alpha 1 and alpha 2 peptides of type I collagen

  • Specific mutations occur in the COL1A1, COL1A2, CRTAP, and LEPRE1 genes

OI congenita

present at birth. Infants with this disease usually have multiple fractures at birth that heal only to give way to new fractures. This results in limb deformities and dwarfism, and may lead to death.

OI tarda

fractures might not appear for some years after birth and then generally stop once adulthood is reached

Osteogenesis Imperfecta (OI)

will demonstrate multiple fractures in various stages of healing and a general decrease in bone mass

bone cortex is thin and porous, and the trabeculae are thin, delicate, and widely separated

• Subtractive Pathology

Achondroplasia

Most common inherited disorder

• results in bone deformity, decreased bone formation and disproportionate dwarfism

  • most common form of dwarfism

• Autosomal dominant gene at 4p chromosome (FGFR3 gene)

  • this gene does not skip generations

  • 50% chance of transmitting it to their children

• The disturbance in endochondral bone formation causes the cartilage located in the epiphyses of the long bones not to convert the bone in the normal manner which impairs the longitudinal growth of the bones.

• Treatment

  • Occasionally, orthopedic surgery may be necessary in the management of complications associated with achondroplasia

  • The Ilizarov procedure has also been used in an attempt to lengthen the shortened limbs

Achondroplasia (radiology)

• Bone age radiographic studies of the left hand to include the distal radius may be used to monitor persons

• images are analyzed to compare the chronologic age with the radiographic bone age by using one of two methods: (1) the atlas matching method, which was established by Greulich and Pyle (GP) in the 1950s; or (2) the point scoring system of Tanner and Whitehouse

Osteopetrosis (Marble bone disease)

• terms used to characterize a variety of dysplasias involving an increase in bone density and defective bone contour, often referred to as skeletal modeling

• Seventy-five percent of autosomal dominant osteopetrosis results from mutations in the CLCN7 gene

Albers-Schönberg disease

autosomal dominant osteopetrosis type II (ADOII), is the most common form of osteosclerotic osteopetrosis

Craniotubular dysplasias

a group of rare autosomal recessive or dominant hereditary diseases which mainly result in abnormal or defective bone contour of the cranium and long bones

• Radiographs are useful in demonstrating this alteration in contour, sclerosis, and changes within the cortical bone

Fibrous Dysplasia

A rare idiopathic condition characterized by the proliferation of fibroblasts in the medullary cavity

• Radiographically, fibrous dysplasia presents as well-circumcised lesions with no periosteal reaction and a “ground glass” matrix due to the decrease in bone density

Osteopetrosis (Radiology)

Radiographic appearance and change in technical factors

both the osteosclerotic and craniotubular hyperostotic disorders are additive conditions and require an increase in exposure factors to adequately penetrate the bony anatomy because of abnormal bone density

adequate radiographic density may never be achieved

demonstrate an increase in the density and thickness of the cortex and an increase in the number and size of trabeculae, with a marked reduction of the marrow space

Additive Pathology

Syndactyly

associated with Apert syndrome

• a genetic syndrome involving mutations of the FGFR2 gene

• characterized by skeletal abnormalities and craniosynostosis

Polydactyly

the presence of an extra digit or digits

• treatment includes surgical intervention and therapy

• Clubfoot

a congenital malformation of the foot that prevents normal weight bearing

• plantar flexion deformity characterized by the fixation of the foot in adduction, supination, and varus with corresponding soft tissue abnormalities

• generally corrected by casting or splinting the foot in the correct anatomic position

Incidence

malformation of the acetabulum

Because the acetabulum is shallow, the head of the femur is displaced superiorly and posteriorly

Larsen syndrome

a disorder that affects the development of bones

Mutation of FLNB gene affecting production of filament B protein

Radiography

are often difficult to interpret in the neonate

anteroposterior (AP) pelvis and bilateral frog-leg views are obtained and compared with standardized lines

Sonography

may be used to diagnose this anomaly early in life through visualization of the cartilaginous structures of the hip

Treatment

immobilization through casting or splinting the affected hip to allow the development of the femoral head and acetabulum, and the formation of a functional joint

Scoliosis

an abnormal lateral deviation of the spine

most commonly with vertebral rotation

Transitional vertebra

Usually LS junction

Cervical ribs at C7

Spina bifida

the failure of the lamina to unite posteriorly, resulting in an incomplete closure of the vertebral canal

• common in the lumbosacral area

• Treatment

  • determined on the basis of the extent of the anomaly and requires the services of a variety of physicians

Radiography (vertebral anomalies)

important in the diagnosis and treatment

requires initial AP or posteroanterior (PA) and lateral standing radiographs

measure the spine’s curvature

Treatment (Vertebral anomalies)

placing the individual in a brace or body cast in persons with curves of 25 to 35 degrees

Surgical treatment with spinal fusion is prescribed for curves greater than 40 degrees

Scheuermann disease (Scheuermann kyphosis)

characterized by an increase in thoracic and thoracolumbar kyphosis

• Diagnosis is obtained through thoracic radiography

  • defined by the presence of irregular vertebral endplates and anteriorly wedged vertebrae

Klippel-Feil syndrome

a congenital syndrome characterized by multiple nonsegmentations and fusions of the cervical spine (Fig. 2.19), spina bifida, Sprengel deformity (undescended scapula), and scoliosis

• caused by gene mutations and can be inherited in an autosomal dominant or recessive manner

Craniosynostoses

A congenital premature closure of one or more of the cranial sutures before the brain is fully formed

cranium continues to grow in the other parts of the skull where the sutures remain unfused to accommodate brain growth, which alters the shape of the head

Often associated with Apert syndrome

Anencephaly

• a congenital abnormality in which the brain is underdeveloped and the cranial vault is incomplete

• abnormality results in death shortly after birth and may be diagnosed before birth by ultrasonography

• Neural tube defect

Osteomyelitis

an infection of the bone marrow and surrounding bone caused by a pathogenic micro­organism spread via the bloodstream (hematogenous) from an infection within a contiguous site, or through direct introduction of the microorganism

Staphylococcus aureus, E. coli, and Group B streptococci

• Signs and Symptoms

• dull pain, heat swelling, and redness in the affected area, and varying degrees of fever

• Contiguous infections

• Direct introduction of microorganism

• Diagnosis

  • The infection spreads rapidly, with the acute stage of osteomyelitis characterized by the formation of an abscess, leading to an inflammatory reaction within the bone that causes a rise in internal bone pressure

  • Elevated ESR or CRP

  • Bone necrosis within 24 to 48 hours not evident radiographically until 14 days after onset.

  • Sequestrum

    • is dead, devascularized bone that appears very dense

  • Involucrum

    • a shell of new supporting bone laid down by the periosteum around the sequestrum

  • Nuclear medicine and MRI

    • MRI demonstrates water-like signal characteristics

  Subtractive Pathology

Tuberculosis

a chronic inflammatory disease caused by Mycobacterium tuberculosis

• usually arises secondary to pulmonary TB and tends to be more advanced and is often left untreated for a longer period compared with pulmonary tuberculosis

  • Pott disease

    • Tuberculosis of the Radiographic appearance

      • the ends of the long bones display a “worm-eaten” appearance, with the disease slowly destroying the epiphyses, spreading to the articular cartilage, and, in some cases, infecting the joint space