Chapter 3 Q&A

Question 1

1. 74 yo woman with acute chest pain and SOB; LAD coronary artery occluded; labs and ECG show acute MI; what would you see in affected heart muscle 4 weeks later?

Answer 1

Collagen rich scar tissue: the necrotic myocardium is replaced by collagen-rich scar tissue weeks to months later

Question 2

2. 4 yo boy falls on rusty nail and punctures skin; wound is cleaned and covered with sterile gauze; what is the initial event in healing process?

Answer 2

Formation of a fibrin clot to fill gap created by the wound (forms on the wounded skin as a barrier to invading microorganisms)

Question 3

3. 82 yo man dies 4 years after developing CHF; has history of multiple MI’s over past 10 years; trichrome stain of heart muscle shows which predominant type of collagen?

Answer 3

Type I (mature scare composed mostly of this)
Type III collagen in early matrix of granulation tissue
Type II in cartilage
Type IV in basement membranes

Question 4

4. 25 yo woman with deep, open laceration over right forearm in motorcycle accidnet; wound cleaned and sutured; which cell type mediates contraction of wound to facilitate healing?

Answer 4

Myofibroblasts: responsible for wound contraction and deforming pathologic process called wound contracture; they express alpha-smooth muscle actin, desmin, and vimentin, and they respond to pharmacologic agents that cause smooth muscle to contract or relax

Question 5

5. What is required for proper collagen assembly in scar tissue?

Answer 5

Vit C

Question 6

6. 70 yo woman with diabetes develops an ulcer on right leg; ulcer bed covered with granulation tissue; what principle cellular components are in bed of wound?

Answer 6

Cells and proliferating capillaries (granulation tissue has these two major components, like the fibroblasts, myofibroblasts and macrophages)

Question 7

7. Which proteins help stimulate healing and angiogenesis in wound of 70 yo woman?

Answer 7

Metalloproteinase (matrix MPs enable cells to migrate by degrading matrix proteins; members of this family include collagenase, stromelysin, and gelatinase)

Question 8

8. 68 yo man presents for repair of abdo aortic aneurysm; atherosclerosis noted at surgery; with renal cortical infarct as a result of surgery, what would be the most likely outcome?

Answer 8

Scar formation: infarct of kidney can heal by fibrosis; ECM framework destroyed

Question 9

9. 40 yo woman has painless lesion on right ear lobe; ears pierced 4 mos ago; what is the path of the lesion?

Answer 9

Maturation arrest of collagen assembly (keloid is exuberant scar tending to progress beyond site of initial injury and recurs after excision); keloids characterized by changes in ratio of type III to type I collagen

Question 10

10. 58 yo woman has lumpectomy for breast cancer; after surgery, firm .3 cm nodule along edge of surgical incision; nodule has chronic inflammatory cells, multinucleated giant cells, extensive fibrosis; how were the cells formed?

Answer 10

Foreign material (granulomatous inflammation is a subtype of chronic inflammation, which develops when acute inflammatory cells cannot digest the injurious agent)

Question 11

11. 57 yo man with history of alcoholism presents with yellow discoloration of skin and sclerae; lab studies show elevated serum levels of liver enzymes (AST and ALT); based on the histology, what could this be attributed to?

Answer 11

Chronic viral hepatitis: hepatocytes form regenerative nodules that lack central veins and expand to obstruct blood vessels and bile flow.

Question 12

12. 10 yo boy trips at school and scrapes palsm of hands; wounds cleaned and covered with sterile gauze; what characterizes healing of superficial abrasions?

Answer 12

Regeneration: superficial abrasions of skin heal by this process; cellular migration is predominant means by which wound surface is reepithelialized
Fibrosis: aberrant healing with collagen-rish scar tissue
Granulation tissue: repair of deep wonds
Primary and secondary intentions: healing in deeper wounds

Question 13

13. What helps restore normal epithelial structure and function in 10 yo boy who tripped?

Answer 13

Contact inhibition of epithelial growth and motility (need basal epithelial cells at wound margin to become activated and reestablish contact with other basal cells through extensive cell migration and mitosis)

Question 14

14. 34 yo woman with benign nevus removed from back; which cell adhesion molecules are part of provisional matrix that forms during early wound healing?

Answer 14

Fibronectins (deposit at site of tissue injury; chemoattractant for variety of cells recruited to wound site over next several days);
cadherins and integrins not part of ECM, but are found at cell surface like selectins

Question 15

15. Which glycoproteins plays important role in regulating migration and differentiation of leukocytes and CT cells during wound healing 34 yo woman with benign nevus?

Answer 15

Integrins

Question 16

16. 29 yo carpenter gets traumatic laceration to left arm; what determines if this wound will heal by primary or secondary intention?

Answer 16

Apposition of edges (primary occurs with closely apposed edges and minimal tissue loss; secondary occurs in gouged wound when edges are far apart and there is substantial tissue loss)

Question 17

17. Activated fibroblasts, myofibroblasts, and capillary sprouts are most abundant in wound of the 29 yo carpenter at which of the following times after injury?

Answer 17

3-5 days
neutrophils 12-24 hours after injury
mature scar tissue 2 weeks after injury

Question 18

18. 9 yo boy with deep laceration over right eyebrow playing ice hockey; wound cleaned and sutured; what are macrophages doing in wound 24-48 hrs after injury?

Answer 18

Phagocytosis

Question 19

19. Which collagen is deposited first during wound healing in 9 yo boy with injury after ice hockey?

Answer 19

Type III (along with proteoglycans, glycoproteins, they make a temporary matrix)

Question 20

20. 16 yo boy suffers concussion during ice hockey game and rushed to ER; CT shows cerebral contusion of left frontal lobe; kid comatose but regains consciousness; what is mediator of scar formation in central nervous system?

Answer 20

Glial cells

Question 21

21. 30 yo firefighter suffers extensive third-degree burns over arms and hands; patient at high risk for developing which complication?

Answer 21

Contracture

Question 22

22. 23 yo man suffers crush injury of foot, becoming secondarily infected; has amputation, then complaint of chronic pain at site of amputation; firm nodule seen at scar site

Answer 22

Neuroma: bulbous lesion consists of disorganized axons and proliferating Schwan cells and fibroblasts; the cut ends not in perfect alignment or are prevented from establishing continuity by inflammation

Question 23

23. 34 yo man with 5-day history of painful sore on hand; .5 cm abscess on extensor surface of left hand that drains thick, purulent material; diapedesis of leukocytes into and around patient’s infected wound occurs primarily where?

Answer 23

Postcapillary venule

Question 24

24. 35 yo pregnant woman with chronic gastritis presents to ER with acute abdo pain; PE shows hepatomegaly, ascites, mild jaundice; patient develops acute hepatic failure and expires; also thrombosis of hepatic veins; there is lesion in distal stomach, what describes the finding?

Answer 24

Ulcer