Introduction to Pathology Flashcards
What is a disease?
Molecular, cellular, tissue, organ, and organismic damage caused by an etiology and dealt through pathologic mechanisms
What is etiology?
Etiology is the cause of a disease (infection, injury, genetic, chemical)
What is pathogenesis?
The mechanisms through which a disease damages the body.
What is a symptom?
Something your patient has recognized and tells you “I have a dry throat”
What is a sign?
A quantitative result of physical or laboratory testing “The patient has a temperature of 102 F and a low white blood cell count”
Is all cell damage irreversible?
No! If cells are minimally hurt they can bounce back by eliminating toxins and sloughing off excess cellular material.
What are hallmarks of cell damage?
Plasma membrane blebs (loss of circular shape).
Ribosomes detached from rough ER
Mitochondrial swelling.
Aggregated centrioles and microtubules.
Increased intracellular volume (maybe to dilute toxins?)
What is hypertrophy? Where does it often occur?
Increase in cell size (not number). This often occurs when cells swell in response to antigens. Another great example is exercise. As you exercise, your muscles grow larger, not more numerous.
What is hyperplasia? Where does it often occur?
Increase in cell number. Hyperplasia is intentional or organized cell proliferation. Non-invasive, non-cancerous, but just an increase in cell number. This can often happen around glands.
What is metaplasia?
Change in cell type! This can happen as a response to toxins in the environment (the columnar cells of the airway become squamous when exposed to cigarette smoke, and the esophageal lining changes drastically under chronic exposure to gastric reflux).
What is dysplasia?
Unorganized, but noninvasive, growth of cells in a tissue. Dysplasia is hindered by the confines of the tissue. It is often a precursor to neoplasia (cancerous growth)
What is neoplasia?
Uncontrolled, invasive growth. The growth can be benign or malignant.
What is atrophy? What are common causes of atrophy?
Decrease in cell size.
- Decreased “load” (you work a muscle less, or change the weight load on your bones and they will change shape)
- Decreased nutrition (no nutrients, cell will shrink to a sustainable size)
- Inhibition of molecules signaling growth “trophic signaling”
- Chronic injury (pancreatitis?)
- Lack of oxygen (cell is starved, can’t survive)
- Increased pressure (bed rest can kill/weaken muscle groups)
- Chronic disease
How do hypertrophic cells show up in microscopic stains?
They’re always larger, can have lots of fluid or fat built up (this would show as clear or very light pink in the stain), and can have enlarged nuclei.
How does hyperplasia show up in microscopic stains?
Increased thickness of tissue (with a semi-conserved shape). Increased number of cells of one type. They will still appear organized.
What would metaplasia look like in a microscope slide?
Epithelial metaplasia would show up as a disruption in a nice consistent wall of epithelial columnar cells (or could be another type) by a clump of clearly divergent cell types. Would be localized. Metaplasia is more common in tissues that can be exposed to irritants and toxins.
What would dysplasia look like in a microscope slide?
You’d have a mass of cells that were not polarized (aren’t maturing normally from the basal membrane to the apical lumen-facing cells. normally apical cells will have more cytosol, maybe even not have their nuclei anymore. Basal cells will be dense and seem directed towards apex). Dysplasia would have a mass of cells that looked like they should maybe be basal cells going all the way throughout. The cells wouldn’t be facing a given direction or anything but would just be filling space where possible. But dysplasia is NONINVASIVE so it would be localized changes in structure.
What would neoplasia look like in a microscope slide?
Invasive, unorganized growth of cells into underlying tissue. Often you’ll see scar-tissue developing as a response, neutrophils also invading the area.
How would you tell the difference between benign and malignant neoplasia in a microscope slide?
Benign seem like they have something of a pattern. Malignant look ugly! They spread out in any direction possible, are a lot more stringy, and have nuclei with very odd shapes.
What phase is used to describe a benign growth?
“___oma”
What phrase is used to describe a malignant growth?
“carcinoma” “sarcoma”
How would hyperplasia or hypertrophy appear different than neoplasia in an organ?
Neoplasia will have a “growth”, something that sticks out and is clearly different in structure. The cells are not differentiated throughout the growth. Hyperplasia or hypertrophy would lead to an increased organ size or thickness, but for the most part structure is conserved. You could have localized increased size, but looking “swollen” versus looking like an extra blob
What is apoptosis?
Mediated/intentional cell death. Usually caused by internal signals (cytochrome c release from mitochondria) but can come from external signals (TNF).
What is necrosis?
Cell death via damage. Not intentional, always caused not-on-purpose
How does an apoptotic cell look different than a normal cell?
The apoptotic cell has fragments of nuclei blown apart all throughout the cell, each encapsulated by a vacuole. Looks like bubble wrap with drops of dye in it.
Normal cell has one large nucleus, circular, most of the other organelles won’t show up in a stain.
In microscope slides, what organelle do you look to to observe cell damage?
The nucleus! It will change structure for both apoptosis and necrosis.
