Intro to Patho Flashcards
Disease definition
An interruption, cessation, or disorder of a body system or organ that is characterized by an etiological agent, signs and symptoms, and changes in anatomy.
What are the causes of disease called?
etiologic factors
What are risk factors?
Variables that increase a person’s probability of having a disease
What is pathogenesis?
sequence of events in cells and tissues between exposure to etiologic agent and manifestation of disease
**How the disease process evolves
Morphology
The fundamental structure or form of cells and tissues
Histology
Study of cells and extracellular matrices of tissues
What is a lesion?
A traumatic or pathological discontinuity of an organ or tissue
Syndrome
Compilation of signs and symptoms characteristic of a disease state
What is an adverse outcome of a disease or treatment?
a complication
What are sequelae?
Lesions or impairments that are caused by or follow disease
Validity
extend to which a measurement tool measures what it is actually intended to.
Example: validity of a sphygmomanometer may be determined by comparing results to intra-arterial measurments
Reliability
Extent to which an observation, if repeated, gives the same results (includes differences in measurement by the observer)
Example: differences in blood pressure measurement technique may vary the reliability between nurses
Standardization
Ways to improve the validity and reliability of measured values.
Test sensitivity
The proportion of people who have a disease and test positive for that disease on a given test
If a person tests negative on a very sensitive test, they do not have the disease.
Test specificity
The proportion of people who do NOT have a disease who test negative for the disease on a given test.
What does specificity indicate?
A true-negative result.
A test that is 95% specific correctly identifies 95 of 100 normal people. The other 5% are false-positive results.
Predictive value
Extent to which a test can predict the presence of a disease
Positive predictive value
proportion of true-positive results that occur in a population
example: People who are diagnosed with breast cancer after finding nodules in a cancer screening would make up the positive predictive value
Negative predictive value
True negative results that occur in a population
example: Proportion of people who do not have breast cancer and also do not have nodules found in the cancer screening make up the negative predictive value
Preclinical stage of disease
It is not clinically apparent, but it is destined to progress to clinical disease
Subclinical disease
Disease is not clinically apparent, and is also not destined to progress.
Clinical disease
Signs and symptoms are present
What is incidence vs prevalence in epidemiology?
Incidence: The number of new cases in a population that is at risk at a specific time.
Prevalene: the measure of existing disease (not just new cases!) in the population as a whole at a specific time.
What is the natural history of a disease?
The disease’s natural progression without treatment
