Introduction to Patho Flashcards
etiology
the underlying cause of the disease
pathogenesis
mechanism that results in the presenting signs and symptoms
sign
objective evidence of a disease
such as blood in the stool, skin rash, cough
symptom
something that can only be detected or sensed by the patient
morphology
study of form and structure
subclinical
not severe enough to present definite or readily observable symptoms
sequelae
a condition that is a consequence of a previous disease or injury
complication
unfavorable evolution
medical problem that occurs during a disease, or after a procedure or treatment
resolution
reduction in the severity of a pathological state
scarring, healing
illness
sickness of deviation from a healthy state
broader more generic and less ominous meaning than disease
disease
biomedical condition with objective data defining it and tends to be chronic
organ system dysfunction
can disease occur without perceiving the presence of an illness
YES
HTN, atherosclerosis, cervical cancer
germ model
caused by a microorganism of some form
causative agent that brings it about
fungal, shingles, port’s disease (TB infxn)
biomedical model
cause and effect relationship
biological factors as causative agents
driving the current practice of medicine
examples of using biomedical model
RA, diabetes, atherosclerosis, CAD
biopsychosocial model
biological, psychological and social factors, play a role in human functioning in the context of disease
ICF model
metaplasia
one adult cell is replaced by another adult cell
arises through genetic reprogramming
hyperplasia
increase in cell number –> increase in organ size
dysplasia
abnormal tissue growth / development, leads to abnormal growth and/or presence of abnormal cells
cancer
what is the etiology of COVID-19
SARS CoV-2 virus
stands for severe acute respiratory syndrome
what is the pathogenesis of COVID-19
inhaled
disturbance in ACE 2/angiotensin; ACE-2 receptor is a functional receptor for the virus
hyper inflated systemic inflammatory response
what is the severity of COVID-19 positively correlated to
level of inflammatory cytokines - TNF IL-6
what are the outcomes of cell injury
reversible injury: normal cell which can lead to stress which causes an adaptation OR injurious stimulus which leads back to cell injury
irreversible injury: necrosis or apoptosis, which is cell death
mechanisms of cell injury
reduced O2 available ischemia/hypoxia/hypoxemia aberrant immune reactions (RA) infectious agents genetic abnormalities (cystic fibrosis) nutritional imbalance (ricketts) physical factors/injury free radical damage
how does reduced O2 availability cause cell injury
decreased blood flow to the tissue reduces O2 availability which then increases reliance on glycolysis, decreased ATP synthesis and lowers pH. Resulting in intracellular accumulation of ions and fluids = SWELLING
how does ischemia cause cell injury
blood flow below normal messes up cell homeostasis
how does hypoxia cause cell injury
deficiency or absence of O2
blood flow may be adequate but O2 content is compromised
how does immune reactions cause cell injury
overly aggressive inflammatory response
autoimmune diseases –> body does not recognize its cells as “Self” and mounts an immune response
how does infectious agents cause cell injury
bacteria, viruses, fungi, mycoplasma, rickettsia, protozoa, prions, helminths
basically invade tissue that causes a response that can lead to cell death or an attack on the immune system which then elicits an inflammatory response altering cell tissue
how does genetic abnormalities cause cell injury
genetic cell changes that can lead to permanent cell damage resulting in genetic abnormalities like down syndromee, marfans syndrome, sickle cell, cystic fibrosis
how does nutritional imbalance cause cell injury
rickets is a Ca or a vit D deficiency resulting in bony neck line, big lumpy joints, bowed legs
inadequate nutrition intake can alter the function of reabsorption for healthy bone and organ function, resulting in permanent damage (irreversible)
how does physical factors/injury cause cell injury
trauma - MVA, athletics, penetrating wounds
Extremes in environmental factors: cold. heat, radiation
reversible or can be irreversible
how does free radical damage cause cell injury
cell death
main consequence of cell injury?
reduced organ function
consequence of mild injury
sub lethal alterations/injury and inflammation in the affected cells with revery causes a return to preinjury state
consequences of more severe injury
lead to tissue alterations and inflammation, repair most likely will not restore damaged tissue and/or tissue function to preinjury state
reversible cell injury
many PT interventions are designed to influence this process
can get back to normal, if not very close to it
chronic cell injury
represents an adaptation to a chronic insult
leads to decrease function –> can’t fix usually
irreversible cell injury
cell death
occurs secondary to apoptosis or necrosis
chronic insult: fat accumulation
may cause materials to accumulate in cells, results in morphologic changes
from binge drinking –> fatty liver
unhealthy eating habits –> atherosclerosis lesions –> cholesterol
chronic insult: atrophy
decrease in cell size secondary to loss of cell substances or cell number
smaller organ/tissue
does NOT imply cells are dead, only reduced functional capacity and/or reduced number of cells
hypertrophy
increase in size of cells –> increase organ
can be physiologic vs/ pathologic
what triggers cell death/apoptosis
regulated, controlled process killing off injured cells
important role in embryogenesis
when the cell is killed, what happens?
it begins to get cleaned by phagocytes engulfs apoptotic cells
lysosomal activation –> ___ –> ____
autophagy –> forms pus
autophagy
catabolism of cellular components
this breakdown of products may be damaging and forms pus
necrosis
form of tissue injury that results in cell death within living tissue
what is necrosis caused by
factors external to the cell or tissue, such as infection, toxins or trauma
normal housekeeping does not occur = accumulation of decomposing cell debris
what does necrosis result in
unregulated digestion of cell components
uncontrolled release of products of cell death into the extracellular space
inflammatory response !!
classic example of necrosis
gangrene
what else can cause necrosis?
unregulated digestion of cell components
