Module 5 Flashcards
(35 cards)
Define “disease”.
Disease is a particular abnormal condition that negatively affects the normal anatomy (structure) or physiology (function) of part or all of an organism.
Acute disease vs. Chronic disease
Acute disease: severe and sudden in onset, distinct, short course (< 3 months)
The flu, broken bone, asthma attack, heart attack
Chronic disease: progress more slowly, ambiguous signs and symptoms, persistent or long-lasting illness that may not be curable
HIV/TB infection, osteoarthritis, asthma, heart disease
Stage: deviations from normal structure or function have begun but no measurable or identifiable changes have occurred
Subclinical (preclinical) Period
related: incubation period
Stage: the beginning of the disease (observable, measureable changes)
onset or baseline
Stage: earlysigns or symptoms which often indicate the onset of adiseasebefore more diagnostically specific signs and symptoms develop
Prodromal period (prodrome)
Clinical stages of disease
exacerbation vs. remission vs. recurrence (relapse)
Exacerbation – increased intensity of disease
Recovery - restoration of normal anatomy or physiology
Remission - reduction of clinical signs or symptoms
Cure – end of medical condition
Recurrence (relapse) – signs and symptoms reappear
Death
Etiologies
idiopathic
iatrogenic
nosocomial
Idiopathic – disease with unknown (unexplained) etiology
Iatrogenic – disease caused by medical examination or treatment
Nosocomial – disease that originates from the hospital/healthcare environment.
T or F: most diseases are multifactorial
T
Incidence vs. prevalence
Prevalence describes the number of cases of a disease existing in a given population during a specific period or at a particular moment; proportion of people affected
How widespread is the disease?
Incidence describes the number of new cases of a disease in a specified period of time (often within a specific population)
Risk of contracting a disease during a specific period of time
Incidence or prevalence?
In 2016, there were 220 new travel related cases of Zika virus infection in Canada.
There are 600,000 people living with heart disease in Canada
84% of Ontarians will suffer from low back pain during their life
Type 2 diabetesis one of the fastest growing diseases inCanadawith more than 60,000 diagnoses made eachyearly
I
P
P
I
Signs vs. symptoms
Signs are objective. They are direct observation(s) made by medical professionals.
Symptoms are subjective. They are described by the patient (or a proxy - their decision maker or caretaker).
Pain, fatigue, nausea, sensory impairment, bowel irritability
Term: Set of medical signs and symptoms that are correlated with each other and, often, with a particular disease or disorder
Syndrome
Sensitivity vs. specificity
The sensitivity of a clinical test refers to the ability of the test to correctly identify patients with the disease (i.e. true positives) = a/(a+c)
The specificity of a clinical test refers to the ability of the test to correctly identify those patients without the disease (i.e. true negatives) =b/(b+d)
Type I error vs. type II error
type I - false positive (test was positive but they do not have the disease)
type II - false negative (test was negative but they do have the disease)
Totipotent vs. pluripotent vs. multipotent stem cells
toti - placenta + embryo (gives rise to total organism)
pluri - 3 germ layers (cannot make placenta)
multi - limited range - haematopoietic stem cells (HSC) - WBCs
Labile tissues vs. stable tissues vs. permanent tissues
Labile tissues have many active stem cells that are ready to replace cells that are frequently depleted or damaged
Skin, gut, airways, bone marrow
Stable tissues - few active stem cells, replicate when needed
Liver, the proximal tubules of the kidney and endocrine glands.
Permanent tissues - non-dividing, contain no stem cells
Nervous tissue and most muscle (ie. the effects of post-stroke on brain)
EXAM Q: Differentiate the types of cell injury.
mild vs. severe cell injury
Injury can be MILD (reversible) or SEVERE (non-reversible)
Most common source of cell injury?
hypoxia - inadequate tissue oxygenation
note: different from ischemia…which is decreased BF
Lactic acid build up can lead to inhibited function of enzymes….like what?
Na/K ATPase - leads to increased intra Na and causing swelling
SO dismutaste (antioxidants)
T or F: Mild injury can be acute or chronic.
What are signs of acute injuries?
T
hydropic changes (intracell water), steatosis (fat)
What are signs of chronic injuries?
hydropic changes (intracell water), steatosis (fat), protein accumulation, tar
What is metaplasia?
process where one mature cell type differentiates into another
How does a severe injury lead to cell death?
necrosis*
Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma which result in the unregulated digestion/disruption of cell components.
Necrosis is almost always detrimental and can be fatal
What is the general process of apoptosis?
Trigger initiates apoptosis
Cell manufactures lethal cocktail of suicidal molecules (caspases) which causes cell death
Metabolism slows down
Cells shrivel
Nucleus destroyed
Membrane blebbing
