Cellular Adaptation and Cell Necrosis

Question 1

Cellular Adaptation

Answer 1

• prolonged exposure of cells to adverse/exaggerated normal stimuli which evokes various changes at level of individual cells, tissues, or whole organs
• once removed… most cells return to normal, some do not

Question 2

What is Atrophy? What are some examples?

Answer 2

• decrease in the size of a tissue, organ, or the entire body
• physiologic: thymus, bones, & ovaries/uterus/breasts after menopause
• pathologic: Alzheimer dementia (BEST), kidneys w/atherosclerosis, testicular atrophy

Question 3

What is Hypertrophy? What is the best example?

Answer 3

• increase in size of tissues or organs due to enlargement of individual cells
• Physiologic: skeletal muscle of body builders due to weights
• Pathologic: LVH (hypertrophy of heart due to HTN)

Question 4

What is Hyperplasia? What is the best example?

Answer 4

• increase in number of cells that can cause enlargement of tissues or organs
• i.e. BPH, pregnant uterus, polyps of colon/stomach

Question 5

Can hyperplasia and hypertrophy be seen together?

Answer 5

Yes, i.e. hyperplastic prostate (BPH) or uterine smooth muscle cells during pregnancy

Question 6

What is Metaplasia? What is the best example?

Answer 6

• change in type of cell
• always pathologic
• i.e. squamous metaplasia of bronchial epithelial cells in long term smokers
• i.e. gastric or glandular metaplasia in Barrett’s Esophagus from GERD

Question 7

What is Dysplasia? What is the best example?

Answer 7

• “dis”ordered tissue growth of tissues resulting from chronic irritation/infection
• pre-cancerous
• cervical epithelia neoplasia or CIN on PAP smear –> cervical cancer

Question 8

What is Anaplasia? List other names both pathologically and clinically?

Answer 8

• undifferentiation and uncontrolled growth of cells

- aka malignancy, carcinoma, cancer, neoplasm

Question 9

List the 5 microscopic hallmarks of anaplasia

Answer 9

1. Pleomorphism (cells and nuclei vary in size and shape)
2. Nuclei irregular and hyperchromatic
3. extremely high N/C ratio (1:1)
4. large nucleoli present w/in nucleus
5. large #’s of mitotic figures

Question 10

What is Cell Necrosis?

Answer 10

death of cells or groups of cells w/in living organism

Question 11

What is the difference between necrosis and autolysis?

Answer 11

• necrosis is seen in the living (w/inflammation)

- autolysis seen in tissues after death

Question 12

What are the different types of necrosis?

Answer 12

1. coagulative
2. liquefactive
3. caseous
4. fat

Question 13

What is the most common type of necrosis? Give examples.

Answer 13

• coagulative necrosis: cell proteins are altered or denatured; often caused by anoxia
• typically occurs in solid internal organs (heart, kidney, spleen, liver)
• i.e. heart tissue undergoing MI

Question 14

What is Liquefactive necrosis? What is the best example?

Answer 14

• dead cells liquefy; soft and gel-like
• brain infarcts (CVA)
• also seen in lung abscess (staph aureus)

Question 15

What is Caseous Necrosis? What is the best example?

Answer 15

• a form of coagulative necrosis where thick, yellow, cheesy substance forms
• i.e. TB, characterized by lung granulomas called Ghon Complex
• Also some fungal infections (histoplasmosis)

Question 16

What is fat necrosis? What is the best example?

Answer 16

• specialized form of liquefaction necrosis caused by action of lipolytic enzymes
• i.e. Pancreas - enzymes are released into fat tissue after rupture of pancreas, causing breakdown into free fatty acids to then bind with calcium forming soaps. Looks like white, calcified specs.

Question 17

What is the difference between wet & dry gangrene?

Answer 17

• necrotic tissue infected by bacteria usually caused by atherosclerosis or DM
• Wet: inflammation, liquefaction (i.e wet decubitus ulcers)
• Dry: dried out necrotic tissue turns black and mummified (dry gangrene)

Question 18

What are dystrophic calcifications? What is the best example?

Answer 18

• necrotic tissue attracts Ca2+ extracellular deposits; can be gritty to rock hard
• calcifications in Atherosclerotic coronary arteries contributes to narrowing of vessels
• Also seen in stenosis, breast cancers, congenital Toxoplasmosis

Question 19

What are Metastatic Calcifications? What is the best example?

Answer 19

• deranged Ca2+ metabolism –> increased serum levels –> deposition of Ca2+ in other places (gallbladder, kidney, bladdr)
• also seen in Vitamin D toxicity, hyperparathyroidism, chronic renal failure