Pathology Flashcards
Define: Hypertrophy, atrophy, hyperplasia, metaplasia
Hypertropy: increase in cell size and metabolic activity
Atrophy: decrease in cell size and metabolic activity
Hyperplasia: increase in cell number
Metaplasia: transformation of one differentiated cell to another
Which cell types are conditioanlly dividng cells? Which cells are non dividing?
Conditional dividing cells: kidneys/liver
Nondividing: cardiomyocyte, neurons, skeletal muscle
What happens during muscle atrophy? Muscle hypertrophy?
atrophy = shrinking of cells
hypertrophy = increased cytoplasm (growth of cell size)
What is an example of hyperplasia?
Squamous epithelial hyperplasia in response to skin irritation. (i.e. lifting weights -> form callous)
What happens when you remove a portion of a healthy liver?
Liver regrows and is relatively normal
What is an example of metaplasia?
Metaplasia = conversion of one differentiated cell to another
One example is in the lungs in response to smoking
Another is the esophageal response to GERD (Barrett’s esophagus)
What are the features to be aware of for neoplasms?
Line of differentiation (i.e. adeno, fibro (connective tissue), chondro (cartilage), rhabdo (skeletal muscle), etc)
Benign of malignant
carcinoma -> malignant epithelial
sarcoma -> malignant connective tissue
oma -> benign (e.g. lipoma)
What are carcinomas? Sarcomas? Lymphomas? Melalnoma?
Which is the most common type of malignancy?
Carcinoma - malignant epithelial neoplasm
Sarcoma - malignant mesenchymal
Lymphoma - malignant lymphocytic
melanoma - malignant nelanocytic
Carcinomas are the most common (instestinal, breast etc. etc.)
What does grading and staging of tumors mean?
Grade is the degree of histologic differentiation. Looking for anaplasia (disorder) and mitotic activity
Stage is evaluation of the extent of tumor spread. Stagin uses TNM T = tissues, N = number of lymph nodes affected, M = metastasis to other organs
What are some causes of cell injury?
Oxygen deprivation
Physical agents
Chemical agents
Infectious agents
Immune system
Genetic disease
Nutritional abnormalities
What happens when Na+/K+ ATPase fails?
Could be caused by a decrease in concentration of ATP. Na+ builds up in cell, causing water to enter cell and cause swelling.
What happens during hypoxia?
Lack of ATP -> loss of cell functions (i.e. Na+/K+ ATPase)
Decrease in pH
mitochondrial damage -> leakage of apoptotic proteins which cause cell damage
What are the differences between necrosis and apoptosis?
Necrosis - always due to injury/pathology
- usually affects groups of cell
- PM ruptures and contents leak out of cell which leads to inflammation
- inflammation is BIG differentiator
Apoptosis - could be on purpose or due to injury
- can occur in only single cells (planned death)
- during breakdown, cell forms apoptotic bodies
- phagocytes pick up apoptotic bodies
- does NOT cause inflamation
What are the key cellular changes in necrosis?
Cell swelling
Increased eosinophilia (pinkness) due to loss of RNA)
Glassy homogenous pattern
Loss of nuclear material
random DNA breaks (karyolysis, pyknosis, karyorrhexis (fragmentation)
What are the cellular changes in apoptosis?
Death of single cells
Cytoplasmic blebbing
Cell Shrinkage
Chromatin condensation
Most organelles intact
Phagocytosis but NO inflammatory response
How can you identify coagulative necrosis?
Typically caused by acute ischemia
Leads to ghost cells (lack of nuclei but cells still intact)
What is liquefactive necrosis?
Typically in brain where portion of the brain liquefies in repsonse to an ischemic event
What is caseous necrosis?
Caseous = cheese like
Gross tissue looks like cheese. Microscopically, cells organized in a granuloma with a central portion of necrosis. (nectric donut)
******** TUBERCULOSIS *******
What is the mechanism of pancreative fact necrosis?
Caused by acute pancreatitis.
Alcohol / gall stones -> hypersecretion of enzymes which lead to cell damage -> activated lipases -> generation of free fatty acids -> free fatty acids + calcium = soap => saponification
What is gangrenous necrosis?
Clinical variant of coagulation necrosis which is characteristically localized to soft tissues of lower limbs due to hypoxia/ischemia
Occurs specifically in the blood vessels
What is fibrinoid necrosis?
special type of necrosis typically seen in immune reaction
