Adaptation, injury, and approach to disease (notes) Flashcards
reversible deficiency of blood flow for the metabolic needs of the tissue (4 minutes for brain, 20 minutes for heart, 2 hours for liver).
Ischemia
ischemic death of tissue usually due to arterial occlusion by a blood clot that formed at the site (thrombosis) or traveled there (thromboembolism).
Infarction
the appearance a dead organ or tissue takes on in a person who remains alive.
Necrosis
programmed cell death, a pathway induced by a tightly regulated intracellular program of activating enzymes that degrade the cell’s own parts.
Apoptosis
a localized area of liquefactive necrosis, usually due to acute necrotizing infection, usually best treated by draining the infected liquid.
Abscess
A single diagnosis that explains all of a patient’s symptoms, signs and other manifestations of disease is most likely the correct diagnosis.
Occam’s razor
Disease has a spectrum of effects on a person. Define adaptation
set of physiologic and morphologic changes, modulating the function of a person, organ or cell, bringing her or him or it to a new altered steady state of homeostasis, which can usually be sustained indefinitely
What type of disease allows adaptation?
mild disease
Describe moderate disease wrt adaptation
Moderate disease causes injury because it exceeds the ability to adapt.
Define injury
the reversible pathophysiologic and morphologic response to a stress or noxious stimulus exceeding the capacity to adapt, but not enough to kill the cell, organ or person.
What disease causes injury too great for a cell, organ or person to survive?
severe disease
Describe the result of slow chronic loss of small amounts of blood from the gastrointestinal tract causes a person’s blood-making organ, the bone marrow, to adapt and make more blood.
anemia
Describe the result to blood loss that is simply too much or too rapid,
the injury to vital organs is irreversible and incompatible with life.
Describe the spectrum from adaptation through injury to death
occurs at the level of tissues (less than a whole organ) and the individual cells that make up tissues and organs.
As a general principle, vital organs have a large reserve capacity
T/F Disease commonly uses up an organ’s reserve capacity silently until it is too late
true
The same spectrum of response to disease occurs at the level of individual body organs. Describe it wrt blood loss and the kidney
- If the blood supply to a kidney becomes inadequate, the kidneys adapts by doing less work. It makes less urine.
- If inadequate blood supply to a kidney becomes chronic, it shrinks; this is the process of atrophy.
- If the inadequacy of blood supply is too severe, the kidney dies.
Death of an organ is called
necrosis
Describe the disease process of atherosclerosis
- atherosclerosis gradually narrows the lumen of critical blood vessels in the heart
- suddenly something (like severe exertion) demands more blood flow than can be delivered
- or something (like a blood clot) reduces blood flow below the minimum needed at rest
- the person dies suddenly.
Disease causes visible manifestations in what? What is the other name for visible manifestations of disease?
cells, tissues, organs and people
morphology
What is the appearance of disease without the aid of a microscope?
gross morphology
What is a term for a discrete visible manifestation of disease?
Lesion
most commonly used for a well circumscribed visible manifestation of a disease
cause of a disease is commonly referred to as what?
etiology
What is normal function?
What is abnormal function, rendered abnormal by disease?
Physiology
Pathophysiology
Describe pathogenesis
the sequence of events in the response of the person, organ or cell to the etiologic agent of a disease, from the initial stimulus to the ultimate manifestation of the disease