Cell Adaptation/Necrosis Flashcards
Prolonged exposure of cells to adverse/exaggerated normal stimuli –> evokes various changes of individual cells/tissues/whole organs. When cause removed, adapted cells revert to normal and some do not (detrimental results)
Cell adaptation
**6 ways cell adapt to change**
- Atrophy
- Hypertrophy
- Hyperplasia
- Metaplasia
- Dysplasia
- Anaplasia
Decrease in size of tissue, organ, or entire body
atrophy
2 types of atrophy
- physiologic
- pathologic
3 examples of physiologic atrophy
- Involution of thymus
- Menopause (ovaries/uterus/breasts)
- Osteoporosis (bones and muscles in elderly thin/prone to fx)
3 examples of pathologic atrophy
- kidneys shrinking due to atherosclerosis
- testicular atrophy
- Alzheimer Dementia
Ischemic organs are typically small or large? What is this an example of?
Small, due to atherosclerosis (hardening of arteries decreases blood supply). An example of pathologic atrophy.
Widening of sulci, narrowing of girations, spares occiput
Pathologic atrophy from Alzheimer’s Disease
**Best example of pathologic atrophy?**
Alzheimer’s Disease
Increase in size of tissues/organs due to enlargement of individual cells
Hypertrophy
Example of physiologic hypertrophy
Enlargement of skeletal muscles in body builders due to weights
Example of pathologic hypertrophy
Enlargement of heart which occurs as adaptation to increased workload (HTN)
What is the best example of pathologic hypertrophy?
Typically seen w/ HTN (enlarged heart)
- Concentric pathologic hypertrophy of left ventricular muscle, an adaptive response to left ventricular pressure overload
Adaptive increase in number of cells, causes enlargement of tissues/organs
Hyperplasia
Example of hyperplastic hyperplasia
Hyperplastic polyps of color or stomach (benign)
Example of hyperplasia in women?
Edometrial hyperplasia due to estrogens (benign, causes vaginal bleeding)
Can hyperplasia and hypertrophy be seen together?
Yes
Example where hyperplasia is seen along w/ hypertrophy in women?
-Physiologic hypertrophy of uterine smooth muscle cells w/ pregnancy is accompanied by hyperplasia
Example where hyperplasia is seen along w/ hypertrophy in men?
-Hyperplastic prostate (BPH- benign prostatic hyperplasia) results in both size AND number of glands and stroma
Adaptive change of one cell type for another cell type to suit the environment
Metaplasia
2 examples of metaplasia
- bronchial epithelium changes w/ smoking cigarettes
- gastric or glandular metaplasia of GE junction in Barrett Esophagus
Is metaplasia reversible? Why?
Yes, it is always pathologic, never physiologic
Normal epithelium in non-smoker changes to which epithelium in smoker?
mucus-secreting ciliated pseudostratified columnar epithelium replaced by stratified squamous epithelium
The #1 type of squamous metaplasia of bronchial epithelium
Squamous Cell Carcinoma
Disordered growth of tissues from chronic irritation or infection
Dysplasia
Pre-cancerous condition
Dysplasia
Best example of dysplastic changes as it relates to disease
Cervical dysplasia (CIN: cervical intraepithelial neoplasia) ** association of dysplasias/cervical cancers w/ HPV
HPV loves which type of epithelium?
Stratified squamous epithelium
Type of mild dysplasia
CIN 1 (cervical intraepithelial neoplasia)
Undifferentiated and uncontrolled growth of cells
Anaplasia (the hallmark of malignant transformation) = cancer
4 names of anaplasia
- Cancer
- Neoplasm
- Carcinoma
- Malignancy
4 examples of anaplasia
- Squamous cell carcinoma of cervix
- Lung cancer
- Malignant Melanoma
- Renal Cell Carcinoma (RCC)
5 microscopic hallmarks of anaplasia
- Cell and Nuclei w/ pleomorphism (varied size/shape)
- Nuclei are irregular and hyperchromatic (purple)
- Super high nuclear/cytoplasmic ratio (N/C ratio is 1:1 and normally is 1:6)
- Large nucleoli within nucleus
- Large numbers of abnormal mitotic figures
Death of cells or groups of cells (tissues) within a LIVING organism
Necrosis
Necrosis in tissues after death of an organism
Autolysis
**4 types of necrosis**
- Coagulative
- Liquefactive
- Caseous
- Fat
Most common form of necrosis
Coagulative necrosis
Type of necrosis when cell proteins are altered/denatured (cooking eggs). Histologically, cell outlines are preserved and cytoplasm is finely granular
Coagulative necrosis
Type of necrosis which occurs in solid internal organs (heart, kidney, spleen, liver) and is caused by Anoxia (lack of O2 in blood supply) Best example?
Coagulative necrosis -Heart tissue w/ MI
Type of necrosis where dead cells liquify due to certain cell enzymes. Tissues become soft/gel like
Liquefactive necrosis
Where does liquefactive necrosis occur most often?
Brain, cells lose contours and liquefy (typical of brain infarct). Soft and transformed into fluid filled cavity
Another example of liquefactive necrosis other than brain?
Bacterial infections in which cavity may develop (abscesses in lungs)
A form of coagulative necrosis where thick, yellowish, cheesy substance forms
Caseous necrosis
2 examples of caseous necrosis
-TB -Fungal infections such as Histoplasmosis
Ghon Complex (development of lung granulomas). Usually heals containing infection.
Caseous necrosis found in TB
Specialized form of liquefacation necrosis caused by action of lipolytic enzymes
Fat necrosis
Example of fat necrosis
-After rupture of pancreas due to trauma or acute pancreatitis, enzymes are released into adjacent fat tissue causing degradation of fat into glycerol and FFA
With pancreatic trauma, once the fat is degraded to form glycerol and free fatty acids (FFA), what do the FFA bind with and form?
Bind with Ca and form soaps causing white calcified specks (a sign of fat necrosis)
Bacterial infection of coagulated tissue leading to inflammation and secondary liquefaction
Wet gangrene
Provides a good medium for infection by bacteria
Necrotic tissues
Wet Gangrene is also called what?
Advanced decubitus ulcers
Necrotic tissue becomes black and mummified
Dry gangrene (necrotic tissue dries out)
What 2 underlying conditions contribute to gangrene?
- Infarction of intestines -
- Infarction in a limb (usually caused by atherosclerosis or diabetes)
Necrotic tissue attracts calcium salts and frequently undergoes calcification (macroscopic deposition of Ca in injured/dead tissues)
Dystrophic Calcifications
- Visible to naked eye
- Range from gritty/sand like grains to firm/rock hard material
Dystrophic Calcifications
4 examples of dystrophic calcifications
Calcifications of:
- Atherosclerotic coronary arteries (narrowing of vessels)
- Mitral/Aortic valves (impeding blood flow = stenosis)
- Breast cancers (seen on mammography)
- Infant periventricular calcifications (congenital toxoplasmosis) - pregnancy and litter boxes
- Deranged calcium metabolism (NOT cell injury).
- Associated w/ increased serum Ca levels, leads to deposition of Ca in other locations
Metastatic Calcifications
Metastatic calcifications are seen in what 3 disorders?
- Hyperparathyroidism
- Vit D toxicity
- Chronic Renal Failure
- Metastatic calcifications forms Ca stones in which 3 organs?
- Due to what?
- Gallbladder
- Kidneys
- Bladder
- (due to precipitation of salts from solution into tissues)