HISTOPATH 1 Flashcards
study of all changes in cells, tissues, and organs that underlie a disease
Pathology
starting point in every disease process
Cells
3 CLASSES
OF CELLS
Labile
Stable
Permanent
Cells frequently dividing to replace lost body cells
LABILE CELL
Replaces majority of body cells due to their limited lifespan
LABILE CELL
example of LABILE cell
Epithelial cells of skin
Exception: cancer cells
(immortalized cells)
Cells not frequently dividing; only divides to replace injured cells
STABLE CELL
example of STABLE cell
Parenchymal cells of liver and kidneys
Cells that do not undergo replication upon maturation
PERMANENT CELL
example of PERMANENT cell
neurons (nerve cells)
4 ABNORMALITIES IN CELL GROWTH
Aplasia
Agenesia
Hypoplasia
Atresia
T/F
Young cells typically undergo maturation with interval in between. There could be abnormalities along the way before it reaches maturation
TRUE
Incomplete/defective development of tissue/organ
Aplasia
abnormalities in cell growth wherein the affected organ shows no resemblance to the normal mature structure
Aplasia
abnormalities in cell growth that usually occur in PAIRED ORGANS (KIDNEYS, GONADS)
Aplasia
Complete non-appearance of organ
Agenesia
Failure of tissue/organ to reach normal mature adult size
Hypoplasia
Failure of organ to form an opening
Atresia
Imperforate anus and microtia (absence of ear canal) are both abnormalities in cell growth called as
Atresia
T/F
Body cells may be exposed to stressful stimuli. Under normal condition, cells will able to adapt (through several adaptation mechanisms). If exposure to stressful stimuli is prolonged and the degree of stress is severe, cells will fail to adapt which can cause injury (reversible or irreversible).
TRUE
6 CELLULAR ADAPTATION MECHANISMS
Atrophy
Hypertrophy
Hyperplasia
Metaplasia
Dysplasia
Anaplasia
Acquired decrease in tissue/organ size
Atrophy
Normal decrease in tissue/organ size as a consequence of maturation
Physiologic atrophy
Decrease
in tissue/organ size is associated
with a disease
Pathologic atrophy
State the cellular adaptation mechanism:
Thymus at puberty
PHYSIOLOGIC atrophy
State the cellular adaptation mechanism:
Decrease in uterus size after birth
PHYSIOLOGIC atrophy
TYPES OF PATHOLOGIC ATROPHY
“HE VAPE”
Hunger/starvation atrophy
Exhaustion atrophy
Vascular atrophy
Atrophy of disuse
Pressure atrophy
Endocrine atrophy
Decreased tissue/organ size if blood supply to an organ becomes reduced/below critical level
Vascular atrophy
Decreased tissue/organ size due to persistent pressure on the organ or tissue that may directly injure the cell or may secondarily promote diminution of blood supply (vascular atrophy)
Pressure atrophy
A correlated types of PATHOLOGIC ATROPHY
Pressure atrophy
Vascular atrophy
Decreased tissue/organ size due to lack of hormones needed to maintain normal size and structure
Endocrine atrophy
Decreased tissue/organ size due to lack of nutritional supply to sustain normal growth
Hunger/starvation atrophy
Too much workload, causing general wasting of tissues – leading to decreased tissue/organ size
Exhaustion atrophy
Inactivity/diminished activity or function causing decreased tissue/organ size
Atrophy of disuse
Increase in tissue/organ size due to increase in cell size making up the organ
Hypertrophy
Increase in tissue/organ size but NO NEW CELLS PRODUCED
Hypertrophy
Increase in tissue/organ size due to increase in cell number making up the organ
Hyperplasia
Increase in tissue/organ size; NEW CELLS PRODUCED
Hyperplasia
Reversible type of hypertrophy
Physiologic Hypertrophy
Normal increase in tissue/organ size due to increased cell size
Reversible
Physiologic
Hypertrophy
Increased tissue/organ size due to increased cell size caused by a disease
Pathologic
Hypertrophy
Increased cell size as a response to a deficiency
Compensatory
hypertrophy
Increase in tissue/organ size when one of the paired organs is removed
Compensatory
hypertrophy
State the cellular adaptation mechanism:
Bulging of skeletal muscles due to frequent exercise
Physiologic
Hypertrophy
State the cellular adaptation mechanism; also state the reason for its occurrence:
Increased size of myocardium (heart muscle)
Pathologic
Hypertrophy
due to HTN or aortic valve disease
cellular adaptation mechanism that may occur if a patient is experiencing hypertension or aortic valve dse
Pathologic
Hypertrophy
(inc. size of myocardium)
cellular adaptation mechanism that may occur if an individual is consistently exercising
Physiologic
Hypertrophy
(bulging of skeletal muscles)
State the cellular adaptation mechanism:
Enlargement of one kidney (renal)
Compensatory hypertrophy
(occur when one of the kidney is removed)
Normal increase in cell no.
Happens in response to a need
Physiologic
hyperplasia
Abnormal increase in cell no.
Pathologic
hyperplasia
T/F
If there is a compensatory hypertrophy, there is also compensatory hyperplasia.
TRUE!!
Hypertrophy and hyperplasia are two different processes but usually occur together. Triggered by the same stimulus.
State the cellular adaptation mechanism:
↑ breast & uterus size during pregnancy
Physiologic
hyperplasia
State the cellular adaptation mechanism:
↑ breast size during puberty due to glandular stimulation
Physiologic
hyperplasia
State the cellular adaptation mechanism:
Erythroid bone marrow hyperplasia (red cell precursor/immature RBCs in the bone marrow may undergo an ↑ in size, usually in individuals living in high altitude)
Physiologic
hyperplasia
what cellular adaptation mechanism that usually occur in individuals living in high altitude
Physiologic hyperplasia
(reversible if they transfer to low altitude)
State the cellular adaptation mechanism:
Graves disease
Pathologic
hyperplasia
*Graves disease is also described as diffuse crowding of epithelial cells
State the cellular adaptation mechanism:
Endometriosis due to inc. estrogen
Pathologic
hyperplasia
State the cellular adaptation mechanism:
TB of cervical lymph nodes (↑ no. of lymph nodules)
Pathologic
hyperplasia
Involves transformation of adult cell type into another adult cell type
REVERSIBLE
Metaplasia
2 types of metaplasia
Epithelial Metaplasia
Mesenchymal Metaplasia
Cells involved in transformation from adult cell type to another adult cell type are epithelial cells
Epithelial Metaplasia
Cells involved in transformation from adult cell type to another adult cell type are connective tissue cells
Mesenchymal Metaplasia
Original tissue: Ciliated columnar epithelium of bronchi
Stimulus: ?
Metaplastic tissue: ?
Stimulus: Cigarette smoking
Metaplastic tissue: Squamous epithelium
Original tissue: Transitional epithelium of bladder
Stimulus: ?
Metaplastic tissue: ?
Stimulus: Bladder trauma
Metaplastic tissue: Squamous epithelium
Original tissue: Columnar glandular epithelium
Stimulus: ?
Metaplastic tissue: ?
Stimulus: Vit K deficiency
Metaplastic tissue: Squamous epithelium
Original tissue: Esophageal squamous epithelium
Stimulus: ?
Metaplastic tissue: ?
Stimulus: Gastric acidity (triggered by excessive coffee
Metaplastic tissue: Columnar epithelium
What is the affected tissue when a person is a persistent cigarette smoker? What will be the resulting metaplastic tissue?
Ciliated columnar epithelium of bronchi –> Squamous epithelium
What is the affected tissue when a person experienced a bladder trauma? What will be the resulting metaplastic tissue?
Transitional epithelium of bladder –> Squamous epithelium
What is the affected tissue when a person has Vit K deficiency? What will be the resulting metaplastic tissue?
Columnar glandular epithelium –> Squamous epithelium
What is the affected tissue when a person consumes excessive coffee causing gastric acidity? What will be the resulting metaplastic tissue?
Esophageal squamous epithelium –> Columnar epithelium
aka Dysplasia
Atypical metaplasia/
Pre-neoplastic lesion
aka Anaplasia
Dedifferentiation
No transformation; only change in cell size, shape, & orientation (cell arrangement)
May lead to cancer, but not necessarily
Dysplasia
Dysplasia: reversible or irreversible?
Reversible
Anaplasia: reversible or irreversible?
Irreversible
With transformation of adult cells into embryonic or fetal cells (young)
Anaplasia
T/F
Neoplasia is also considered as a cellular adaptation mechanism
FALSE
Causes of cell injury
Anoxia
Infectious agents
Mechanical agents
Chemical agents
No. 1 cause of cell injury
Anoxia (O2 deprivation) - can also lead to cell death
Type of injury wherein the affected cell may recover
Reversible Injury
Type of injury wherein the affected cell will never recover (further undergo cell death); considered as a point of no return
Irreversible injury
Duration for a hypoxic injury to be IRREVERSIBLE in neurons
3-5 minutes
Duration for a hypoxic injury to be IRREVERSIBLE in myocardial cells and hepatocytes
1-2 hours
Duration for a hypoxic injury to be IRREVERSIBLE in skeletal muscles
many hours
Gross changes that can be observed to assume that the cell injury is still REVERSIBLE
- Organ pallor/pale
- Increased organ weight
Earliest microscopic changes to assume that the cell injury is still REVERSIBLE
- Cellular swelling (reason for inc. wt) – 1st to occur
- Fatty degeneration
IRREVERSIBLE INJURY changes are due to
Enzymatic digestion of cells
Protein denaturation
To determine that the cell injury is IRREVERSIBLE, these cell parts are observed
Cytoplasm
Nucleus
Cytoplasmic changes in irreversible injury
- Larger cells “cloudy swelling”
- ↑ eosinophilia (orange or bright pink cytoplasm)
Nuclear changes in
irreversible injury
- Pyknosis – nuclear condensation (small nucleus)
- Karyorrhexis – nuclear fragmentation/segmentation
- Karyolysis – dissolution of nucleus
ending of irreversible injury
CELL DEATH
PATTERNS OF CELL DEATH
Apoptosis
Necrosis
Physiologic (programmed) cell death
Apoptosis
Normal cell death for all cells except for permanent cells (neuron)
Apoptosis
Death of single cell in a cluster of cells
Apoptosis
Course of events in APOPTOSIS
Cell shrinkage →
Intact membrane integrity →
No leakage of cellular components →
NO INFLAMMATION
Course of events in NECROSIS
Cell swelling →
Non-intact membrane →
Leakage of cellular components →
INFLAMMATION
Pathologic (accidental) cell death
Necrosis
5 Chief morphologic features in apoptosis
- Chromatid condensation
- Chromatid fragmentation
- Cell shrinkage
- Cytoplasmic bleb formation
- Phagocytosis of apoptotic cells – removed by neighboring cells
TYPES OF NECROSIS
Coagulative
Liquefactive
Caseous
Fibrinoid
Fat
Gangrenous
Necrosis due to sudden cut off of blood supply (O2)/ischemia
Coagulative
necrosis
Hydrolytic enzymes’ action is blocked (lysozyme released upon cell death) in this type of necrosis
Coagulative
necrosis
MICROSCOPIC APPEARANCE of coagulative necrosis
Preserved cell
outline, empty
(ghostly)
GROSS APPEARANCE of coagulative necrosis
Somewhat firm,
boiled-like
material
Coagulative necrosis is usually common in these organs
Solid organs (liver, kidneys, myocardial infarct)
Softening of organs due to action of hydrolytic enzymes
Liquefactive
necrosis
Complete digestion of cells
Liquefactive
necrosis
GROSS APPEARANCE of liquefactive necrosis
Soft, liquefied, creamy yellow
Liquefactive necrosis usually occur in these conditions
Brain infarct
Suppurative bacterial infection
Coagulative + Liquefactive
Caseous
necrosis
cheese-like
Caseous
necrosis
MICROSCOPIC APPEARANCE of caseous necrosis
Amorphous granular debri surrounded by granulomatous inflammation
GROSS APPEARANCE of caseous necrosis
Greasy
resembling
“cheese”
Caseous necrosis is usually seen in these condition
TB
Fibrin deposition in vessel wall
Fibrinoid
Necrosis
MICROSCOPIC APPEARANCE of Fibrinoid Necrosis
Thickened blood vessels
GROSS APPEARANCE of Fibrinoid Necrosis
NO GROSS changes!!!
Fibrinoid necrosis usually occur in this condition
Immune reactions of the blood vessels