Pathophysiology I: Comprehensive Exam Review

Vocabulary practice flashcards covering fundamental pathophysiology concepts across six course units: introduction and epidemiology, cellular adaptations and injury, genetic disorders, neoplasia, integumentary conditions and burns, and musculoskeletal diseases.

Pathophysiology

The study of abnormal physiological processes associated with disease or injury, focusing on how diseases begin, why homeostatic mechanisms fail, and how compensatory changes produce signs and symptoms.

Clinical Manifestations

The observable and experiential indicators—comprising objective signs and subjective symptoms—that a patient exhibits as a result of a disease process.

Signs

Objective clinical findings that can be measured or observed by an examiner, such as a fever of $38.5\,^\circ\text{C}$, a rash, or swollen joints.

Symptoms

Subjective complaints that are directly experienced and reported by the patient, such as pain, nausea, and fatigue.

Etiology

The cause(s) or origins of a disease, which may be intrinsic (e.g., genetic mutations, autoimmunity) or extrinsic (e.g., infectious pathogens, toxins, trauma).

Iatrogenic

A condition, injury, or adverse effect resulting directly from medical treatment, surgical intervention, or diagnostic procedures.

Pathogenesis

The step-by-step sequence of events by which an etiologic factor leads to structural and functional cellular and tissue alterations, culminating in clinical disease.

Incidence

The rate of occurrence of new cases of a specific disease or condition in a specified population over a defined period of time.

Prevalence

The total number of all existing cases of a disease present within a given population at a particular point in time or over a designated time period.

Allostasis

The physiological processes that maintain or restore stability (homeostasis) through active change when environmental or internal conditions fluctuate.

Allostatic Overload

The cumulative physiological wear and tear, or organ and tissue damage, resulting from compensatory stress responses that are excessive, chronic, or inadequately regulated.

Syndrome

A recognized cluster or set of signs and symptoms that occur together as part of a single disease process, frequently with an uncertain etiology or pathogenesis.

Atrophy

A decrease in cell size and function caused by diminished workload, loss of innervation, ischemia, nutrient deprivation, endocrine decline, pressure, or aging, mediated by organelle degradation via autophagy.

Hypertrophy

An increase in the volume of individual cells without an increase in cell number, driven by accelerated synthesis of structural proteins and organelles in response to heightened functional demand or hormonal stimulation.

Hyperplasia

An increase in the total number of cells in an organ or tissue, resulting in enlarged tissue mass in response to hormonal stimulation, increased physiological demand, or persistent chronic injury.

Metaplasia

A reversible cellular adaptation where one adult, differentiated mature cell type is replaced by another cell phenotype that is better equipped to survive persistent, chronic environmental stress.

Dysplasia

Disordered cellular growth and maturation characterized by pleomorphism, loss of tissue architecture, hyperchromatic enlarged nuclei, and an elevated nuclear-to-cytoplasmic ratio, often representing a premalignant lesion.

Hydropic Swelling

A rapid, reversible cellular swelling caused by failure of the energy-dependent $\text{Na}^+/\text{K}^+\text{-ATPase}$ pump, which allows sodium to accumulate inside the cell and draw in excess water.

Coagulative Necrosis

A form of necrotic cell death typically caused by ischemia, characterized by degradation and loss of cell nuclei, cell disintegration by lytic enzymes, and temporary preservation of basic tissue architecture.

Liquefactive Necrosis

A pattern of necrosis characterized by rapid enzymatic dissolution of dead tissue into a viscous liquid mass or abscess cavity, typically seen in localized bacterial infections and brain infarcts.

Caseous Necrosis

A distinct form of tissue necrosis characteristic of tuberculosis, presenting microscopically as a granuloma with Langhans giant cells and epithelioid macrophages surrounding soft, friable, "cheesy" granular debris.

Apoptosis

An energy-dependent, programmed pathway of cell death that selectively disassembles unwanted or damaged cells into membrane-bound apoptotic bodies without rupturing the membrane or triggering inflammation.

Heat-Shock Proteins

Intracellular molecular chaperones (such as HSP70) that recognize newly synthesized or unfolded polypeptides and use ATP to refold them into functional three-dimensional conformations under conditions of cellular stress.

Teratogen

Any environmental, chemical, or biological agent capable of inducing congenital structural or functional malformations during prenatal development, particularly during the first $8\,\text{weeks}$ of gestation.

TORCH Complex

An acronym designating a cluster of maternal infectious pathogens—Toxoplasmosis, Others (syphilis, VZV, HIV, parvovirus B19), Rubella, Cytomegalovirus, and Herpes simplex virus—that cause severe congenital fetal anomalies.

Aneuploidy

A genomic condition characterized by an abnormal number of chromosomes in a cell, such as missing a single chromosome (monosomy) or possessing extra chromosomes (polysomy/trisomy).

Down Syndrome (Trisomy 21)

The most common chromosomal disorder, caused by an extra chromosome 21, manifesting with cognitive disability, muscular hypotonia, low-set ears, epicanthal folds, a protruding tongue, and congenital heart defects.

Klinefelter Syndrome

A sex chromosome disorder in genetic males characterized by one or more supernumerary X chromosomes ($47,\text{XXY}$), leading to hypogonadism, testicular atrophy, gynecomastia, tall stature, and reduced testosterone.

Turner Syndrome

A sex chromosome disorder in females resulting from complete or partial monosomy of the X chromosome ($45,\text{X}$), presenting with short stature, a webbed neck, streak fibrous ovaries, amenorrhea, and sterility.

Cystic Fibrosis

An autosomal recessive single-gene disorder caused by mutations in the epithelial chloride ion transporter, resulting in abnormally viscid secretions that obstruct airways, destroy pancreatic tissue, and cause chronic respiratory failure.

Hemophilia A

An X-linked recessive bleeding disorder caused by a deficiency or qualitative defect of coagulation Factor VIII, primarily affecting males and characterized by spontaneous or post-traumatic hemorrhage.

Anaplasia

The loss of cellular differentiation, specialized function, and tissue architectural organization relative to the cell of origin, serving as a defining histological hallmark of malignant neoplasms.

Proto-oncogene

A normal cellular gene encoding growth factors, receptor proteins, signal transducers, or transcription factors that promote physiological cell proliferation and survival, but which can mutate into a cancer-promoting oncogene.

Tumor Suppressor Gene

A normal gene encoding proteins that restrain cell cycle progression, repair damaged DNA, or trigger apoptosis; loss-of-function mutations in both alleles are generally required to contribute to tumorigenesis.

Retinoblastoma (Rb) Gene

A classic tumor suppressor gene encoding the nuclear protein pRb, which acts as the master cell cycle checkpoint by binding and sequestering E2F transcription factors to halt DNA synthesis.

p53 Gene

A tumor suppressor gene termed the "guardian of the genome" that halts the cell cycle at $G_1/S$ upon detecting DNA damage to permit repair or initiates apoptosis if damage is irreparable; mutated in over $50\%$ of human cancers.

Carcinogenesis

The multistep biological process of malignant transformation, divided into initiation (irreversible DNA mutation), promotion (clonal proliferation of initiated cells), and progression (acquisition of malignant phenotypic features).

TNM Staging System

A standardized clinical evaluation system that assesses the anatomical extent and spread of malignant tumors based on primary tumor size (T), regional lymph node involvement (N), and presence of distant metastasis (M).

Cancer Cachexia

A systemic wasting syndrome associated with advanced malignancies, characterized by anorexia, accelerated hypermetabolism, generalized asthenia, and progressive loss of skeletal muscle mass and adipose tissue.

Macule

A primary nonpalpable, flat, circumscribed skin discoloration up to $1\,\text{cm}$ in diameter that is level with the surrounding skin surface.

Papule

A primary solid, palpable, circumscribed skin elevation measuring less than $5\,\text{mm}$ in diameter.

Vesicle

A small, primary, elevated, fluid-filled blister measuring up to $5\,\text{mm}$ in diameter located within or beneath the epidermis.

Lichenification

A secondary skin lesion characterized by leathery epidermal thickening, coarsened skin markings, and increased skin furrows resulting from chronic scratching or persistent rubbing.

Herpes Zoster

A painful neurocutaneous eruption caused by reactivation of latent varicella-zoster virus within sensory dorsal root or trigeminal ganglia, presenting as grouped vesicles along a unilateral dermatomal distribution.

Impetigo

A highly contagious, acute superficial bacterial skin infection caused by Staphylococcus aureus or Group A Streptococci, marked by vesicles that rupture into golden-yellow, "honey-colored" crusts.

Psoriasis

A chronic T-cell-mediated autoimmune inflammatory skin condition characterized by hyperproliferative epidermal keratinocytes, manifesting as erythematous plaques covered by thick, silvery micaceous scales on extensor surfaces.

Atopic Dermatitis

A chronic, relapsing, highly pruritic inflammatory dermatosis characterized by lichenification in flexural folds, compromised barrier function, and a strong association with the atopic triad (eczema, allergic rhinitis, asthma).

Deep Partial-Thickness Burn

A second-degree thermal injury involving the entire dermis while sparing deep hair follicle appendages, presenting as a mottled, waxy-white wound surrounded by erythema that typically requires excision and skin grafting.

Full-Thickness Burn

A third-degree thermal injury destroying the epidermis, entire dermis, and underlying subcutaneous tissue, producing a leathery, hard, non-elastic eschar that is white, cherry-red, or charred black.

Burn Shock

A complex state of hypovolemic and distributive shock following extensive thermal injury, caused by systemic capillary leak, rapid intravascular fluid/protein loss into tissues, generalized edema, and cellular $\text{Na}^+$/water influx.

Compartment Syndrome

An orthopedic emergency characterized by increased interstitial tissue pressure within an enclosed osteofascial muscle compartment, causing compromised capillary perfusion, severe ischemic pain, paresthesias, and tissue necrosis.

Osteoporosis

A systemic metabolic bone disease characterized by microarchitectural deterioration of bone tissue where osteoclastic resorption outpaces osteoblastic bone formation, resulting in reduced bone mineral density and fragility fractures.

Rickets

A pediatric metabolic bone disorder characterized by inadequate mineralization of newly synthesized osteoid at the epiphyseal growth plates prior to closure, typically resulting from vitamin D deficiency and presenting with soft, bowed long bones.

Osteomalacia

An adult metabolic bone disorder marked by defective mineralization of the organic bone matrix after epiphyseal plate closure, leading to soft bones, generalized skeletal tenderness, proximal muscle weakness, and pseudofractures.

Paget Disease of Bone

A chronic metabolic bone condition initiated by localized, excessive osteoclastic resorption followed by disordered, hyperactive osteoblastic bone formation, producing structurally fragile, deformed, and enlarged woven bone.

Osteomyelitis

A serious infectious process involving cortical bone and the medullary cavity, most commonly caused by Staphylococcus aureus binding to bone collagen via hematogenous spread or direct traumatic inoculation.

Duchenne Muscular Dystrophy

An X-linked recessive degenerative myopathy caused by absence of the structural membrane protein dystrophin, resulting in progressive muscle fiber necrosis, proximal weakness, calf pseudohypertrophy, and loss of ambulation.

Gower Sign

A classic clinical sign of proximal muscle weakness where a child must use their hands to physically "climb up" their own legs and thighs to rise from a seated position on the floor.

Myasthenia Gravis

An autoimmune disorder caused by autoantibodies that bind, block, and degrade post-synaptic nicotinic acetylcholine (ACh) receptors at the neuromuscular junction, leading to muscle weakness and pathological fatigability.

Fibromyalgia

A chronic non-articular syndrome characterized by widespread musculoskeletal pain lasting longer than $3\,\text{months}$, accompanied by tenderness at specific anatomical pressure points, hyperalgesia, fatigue, and unrefreshing sleep.

Osteoarthritis

A progressive, non-inflammatory degenerative joint disease caused by biomechanical and enzymatic breakdown of articular cartilage, accompanied by subchondral bone sclerosis, osteophytes, and activity-induced joint pain relieved by rest.

Heberden and Bouchard Nodes

Palpable bony osteophyte enlargements characteristically seen in osteoarthritis of the hands, affecting the distal interphalangeal (DIP) joints and proximal interphalangeal (PIP) joints, respectively.

Rheumatoid Arthritis

A chronic, systemic autoimmune disease characterized by symmetric inflammatory synovitis, formation of invasive vascularized pannus tissue, destruction of articular cartilage, and joint stiffness lasting over $1\,\text{hour}$ in the morning.

Swan Neck and Boutonniere Deformities

Characteristic digit deformities in advanced rheumatoid arthritis; the first exhibits PIP hyperextension with DIP flexion, while the second exhibits PIP flexion with DIP hyperextension.

Ankylosing Spondylitis

A chronic inflammatory arthritis of the axial skeleton characterized by sacroiliitis, erosive vertebral inflammation, and progressive bony bridging that produces fusion of the spine ("bamboo spine").

Septic Arthritis

A medical emergency characterized by purulent closed-space infection of a synovial joint cavity, typically caused by Staphylococcus aureus or Neisseria gonorrhoeae, presenting with acute swelling, heat, and severe pain.

Podagra

An acute, exquisitely painful inflammatory monoarthritis of the first metatarsophalangeal (MTP) joint caused by the deposition and phagocytosis of monosodium urate crystals in gout.