Looks like no one added any tags here yet for you.
pathology
study and diagnosis of disease
physiology
study of physical and biochemical functions of living organisms
pathophysiology
study of abnormalities in physiologic functioning of living beings
four interrelated topics of pathophysiology
1) etiology
2) pathogenesis
3) clinical manifestations
4) treatment
etiology
study of the cause of disease
(why did this happen?)
two types of etiology
idiopathic (unknown cause)
iatrogenic (unwanted/accidental cause)
example of multifactorial disease
coronary heart disease
(many things cause It including: diet, cigarette smoking, mental stress, genetic, high BP...)
risk factor
factor present in pt. which increases chances of disease arising (helpful in disease prevention)
congenital disease definition and example
present at birth
spina bifida
degenerative disease definition and example
gets worse as time goes on
Alzheimers or MS (multiple sclerosis)
iatrogenic disease definition and example
accidental/ unwanted side effect of medical treatment
anemia caused by chemotherapy
idiopathic disease definition and example
unknown causes
some forms of epilepsy
immunologic disease definition and example
abnormal weakness/susceptibility of immune system
rheumatoid arthritis or HIV/AIDS
infectious disease definition and example
commonplace virus, bacteria entering body
TB, influenza (flu), measles, cholera, etc...
neoplastic disease definition and example
abnormal growth of cells
cancers
metabolic disease definition and example
processing of the metabolism
central obesity
nutritional disease definition and example
lacking in one/all nutritional category
iron deficiency anemia
physical agent-induced diseases definition and example
anything chemical that is airborne that can affect the human body
asbestosis, mold exposure, CO2 poisoning
something to keep in mind with etiology
"correlation does not imply causation"
Someone who's never smoked cigarettes can get lung cancer, or, someone who doesn't drink a lot can get liver cirrhosis.
pathogenesis
Development/ evolution of a disease.
(from stimulus to expression of disease via chain of cell --> tissue --> organ --> system)
clinical manifestations
signs and symptoms of disease
sign vs symptom
sign: SEEN (can be tested)
symptoms: FELT (only by pt.)
examples of signs
enlarged lymph nodes, vomiting, high BP, high BGL, bruising, swelling...
examples of symptoms
headache, anxiety, nausea, fatigue, sore throat....
syndrome
when causes (etiology) of signs/symptoms haven't been determined (obscure)
EX: AIDS when first discovered
which of the following is an example of a clinical manifestation SIGN?
A. nausea
B. bruising
C. headache
D. loss of appetite
B. Bruising
what are the 5 stages of clinical manifestation?
1) latent (incubation) period
2) prodromal period
3) acute phase
4) latent period
5) subclinical stage
stage 1 clinical manifestation
"latent period" or "incubation period"
from inoculation (exposure) to first showing signs/symptoms
stage 2 clinical manifestation
"prodromal period"
nonspecific signs and symptoms arise (these are linked to many types of sickness/disease/ailments...i.e. cough, fever, headache...)
stage 3 clinical manifestation
"acute phase"
disease/illness at full intensity
stage 4 clinical manifestation
"latent period" or "decline"
time when signs/symptoms become mild, silent, or disappear
stage 5 clinical manifestation
"subclinical stage"
time when "normal" functioning returns, disease processes can also simply be well established by this point (EX: chronic renal disease)
acute disease
signs/symptoms develop rapidly but the disease lasts only a short time
chronic disease
signs/symptoms develop gradually and continues over a long period of time
exacerbation
increase in the severity of a disease or its signs/symptoms
remission
the temporary, partial, or complete disappearance of the symptoms of a disease without having achieved a "cure"
convalescence
stage of recovery after a disease, injury, or surgical procedure
sequela
subsequent pathologic condition resulting from an acute illness
(EX: post acute rheumatic inflammation...heart having scaring/deformation forever)
Treatment Implications
understanding the etiology, pathogenesis, and clinical manifestations tell us which treatment is best
abnormal vs normal in health care
someones "abnormal" could be someone else's "normal" It is very important to compare disease in a carefully selected "population" (think stats)
reliability
test's ability to give same results repeatedly
(imagine a target, hitting the far right corner repeatedly is reliable not valid)
validity
degree to which that measurement is the "appropriate/correct" value
(imagine a target hitting the bullseye repeatedly is both reliable for its repetition AND valid for its "correct" value)
positive predictive value
disease is PRESENT if test is POSITIVE
(YES disease if +)
negative predictive value
disease is ABSENT if test is NEGATIVE
(NO disease if -)
sensitivity
chance that a test will be POSITIVE when applied to a person WITH a disease
EX: "strep throat swab with sensitivity of 80%" = 20% will test negative and HAVE strep (false negative)
specificity
chance that a test will be NEGATIVE when applied to a person WITHOUT a disease.
EX: "strep throat swab with specificity of 95%"
=
5% of people test positive to having when they don't (False Positive)
factors that influence "normality"
1) culture (poor vs rich)
2) age (infant HR vs elderly)
3) gender (hemoglobin in men vs women)
4) situational (high vs low altitude)
5) time (day vs night)
patterns of disease distribution types
endemic
epidemic
pandemic
endemic
native/confined to a particular region or people
EX: chicken pox outbreak in a classroom of children
epidemic
spread of a disease to many people at the same general time
EX: H1N1 influenza ("swine flu")
pandemic
spread to large geographic areas (world wide not just targeting one population)
EX: ebola when It came across seas to US/other countries
which of the following is an example of a factor that would affect the epidemiology of a particular disease?
A. predictive value
B. southeast Asian ethnicity
C. circadian rhythms
D. clinical manifestions
B. Southeast Asian ethnicity
Which of the following is an example of primary prevention?
A. Maintaining routine immunizations
B. Screening for cancer
C. Rehabilitating after a stroke
D. Performing monthly breast examinations
A. Maintaining routine immunizations
what are the three levels of prevention
primary, secondary, tertiary
primary prevention
lowering the susceptibility of a pt. getting a disease or reducing their ability to get exposed
EX: have pt. quit smoking
secondary prevention
early detection, screening, and management of disease
EX: early screening for breast cancer, getting lumps removed if potentially risky
tertiary prevention
rehab, supportive care, reducing disability, and restoring effective functioning
EX: oxygen and aspirin given to a pt. who's had past MI
3 ways cells respond to injury
1) withstand (reversible)
2) adapt (reversible)
3) cell death (irreversible)
Hydropic swelling (oncosis)
cellular swelling due to accumulation of water
results from broken/damaged sodium-potassium (Na+/K)...creates a gradient that makes water ENTER the cell = swelling
intracellular accumulation
Excess accumulation of substances in cells which leads to cell injury b/c of toxicity, immune response, taking up excessive space needed for functioning.
(anything from excess lipids, carbs, proteins, inorganic pigments, inorganic particles)
atrophy
decreased cell size, as well as reduced functioning (differentiation) in an attempt to save energy.
what can cause atrophy of cells
disuse, denervation, ischemia, nutrient starving, lack of endocrine signaling, persistent cell injury
hypertrophy
increase in cell mass/size in response to physiologic (body building) and pathophysiologic (heart muscle enlargement due to high BP) demands.
hyperplasia
increase in cell number (in cells capable of undergoing mitosis). Can be either physiologic or hormonal.
metaplasia
replacement of one differentiated cell type with another
adaptation: a cell is replaced by one that is better suited to tolerate injurious stimulation
(EX: ciliated columnar epithelium converts into squamous epithelium)
dysplasia
disorganized appearance of cells because of abnormal variations in size, shape, and arrangement
(adaptation gone wrong)
necrosis
cell death via rupture, messy, inflammation
(due to ischemia or toxic injury)
apoptosis
cell death via "suicide", clean, no inflammation
what are the 4 types of necrosis?
1) coagulative
2) liquefactive
3) fat (adipose)
4) caseous
Coagulative necrosis
degradation of cell structures (nucleus, membrane, etc)
"black"
marked by mitochondrial dysfunction (begins with ischemia)
EX: bed sores, necrosis from diabetes in feet
liquefactive necrosis
produced by liquification of lysosomal enzymes which creates a cyst/abscess of dead tissue
"wet"
EX: brain cysts
fat "adipose" necrosis
death of adipose tissue as a result of trauma or pancreatitis
"chalky"
fats are hydrolyzed into glycerol and fatty acids
caseous necrosis
"clumpy cheese"
EX: lung damage from TB
gangrene
cell death in a large area of tissue which occurs when there is no blood supply to a part of the body
what are the three types of gangrene
1) dry (dry, black, wrinkled)
2) wet (liquefactive)
3) gas (anaerobic bacteria)
apoptosis by external pathways
neighboring cells give signals for each other to stay alive
if these signals are removed, cell death program is activated (fas ligand
apoptosis by internal pathways
DNA damage that is beyond repair, mitochondrial damage with leakage apoptosis activators, high levels of p53 protein
which type of irreversible cell injury initiates an inflammatory response?
A. apoptosis
B. necrosis
C. hydropic swelling
D. intracellular accumulations
B. necrosis
ischemia and hypoxic injury
ischemia (low blood supply) causes hypoxia (low O2 levels)
poor perfusion = low levels of power (ATP) in cell
ischemia - re perfusion injury
restoring O2 can cause cell injury rather than reversing it
calcium overload (due to low ATP, ion pumps don't work!) which leads to apoptosis
nutritional injury
need adequate fats, proteins, carbs, vitamins for cell functioning and ATP
some cells more likely to get injury than others (low iron intake affects RBCs and anemia or vitamin D with bones)
infectious and immunologic injury
-bacteria: release of endo- or exotoxins which triggers body's immune system to self attack
-virus: gain entry into host and replicate its own DNA to cause cell injury (ex: Hep. B virus)
chemical injury
toxic chemicals, poisons, or pollutants cause cellular injury (direct or indirect)
direct: lead poisoning (on neural tissue)
indirect: carbon tetrachloride (in cleaning agents) converts into CCl3- in liver, causing liver failure
physical and mechanical injury
-Extremes in temperature
-Abrupt changes in atmospheric pressure
-Mechanical deformation
-Electricity
-Ionizing radiation
in what two ways does radiation effect cells
1) genetic damage (changes the DNA code)
2) acute cell destruction (gonadal, mucosal, fetal, hematopoietic)
somatic death
death of the entire body
-cool, pale, diaphoretic (clammy), blood pooling, rigor mortis, etc
congenital disorder
disorder present at birth
(can be genetic or environmental)
congenial malformation
structural defects caused by errors in fetal development
(typically genetic, but can also be environmental)
diploid (2n)
two copies of each chromosome (23 + 23 = 46)
haploid (n)
unpaired chromosomes (23) (get one set from egg and one from sperm)
autosomes
first 22 pairs of chromosomes
sex chromosomes
last pair of chromosomes (#23) what differentiates a man (XY) vs a woman (XX)
four types of genetic disorders
1) chromosomal abnormalities
2) mendelian single-gene disorders
3) non-mendelian single-gene disorders
4) polygenic / multifactorial disorders
chromosomal abnormalities
wrong NUMBER of chromosomes (called aneuploidy)
change in shape of one or more chromosomes
aneuploidy
wrong number of chromosomes (either >46 or <46)
(caused by nondisjunction)
monosomy
gamete lacking 1 chromosome
polysomy
gamete having too many chromosomes
Example of Autosomal Aneuploidy
-Trisomy 21 (Down Syndrome)
-Trisomy 18 (Edwards Syndrome)
-Trisomy 13 (Patau Syndrome)
"Trisomy" meaning
having 3 sets of a chromosomal "pair" (should only be 2 in a pair not 3)
Example of Sex Chromosome Aneuploidy
-Klinefelter Syndrome (extra X in males: so its XXY or XXXY)
-Turner Syndrome (monosomy X in females: one X no Y)