Trauma and Infections (Lab)

Question 1

Define:
Abrasion
Contusion
Laceration
Fracture

Answer 1

• loss of epidermis by frictional forces
• Rupture of blood vessels (bruise)
• Tearing of tissue (bridging of soft tissue)
• skeletal injruy

Question 2

What are coup and contrecoup?

Answer 2

Coup is on the side of impact

Contrecoup is on the opposite side of impact

Question 3

What causes marbling of skin?

Answer 3

Perivascular bacteria cause a reaction between Hemoglobin and hydrogen sulfide resulting in discoloration of the skin

Question 4

Define:
Puncture wound
Incision
Hesitation mark
Defensive incision
Chop wound

Answer 4

• deeper that wide
• cut with clear margins (no bridging)
• non fatal incisions (often seen in suicide)
• Wounds on the hands and arms
• Wedge cut

Question 5

What is the most sensitive histological finding of acute ionizing radiation?

Answer 5

Vascular dilation

Question 6

What serious affect may be seen 120 days after ionizing radiation?

Answer 6

Severe anemia. Hematopoietic stem cells are a big target of radiation and RBCs live for about 120 days.

Question 7

What imaging finding is pathomneumoic of Anthrax?

Answer 7

Mediastinal widening

Question 8

What are the toxins of Anthrax?

Answer 8

A toxin is made up of edema factor and lethal factor.
EF induces binds calcium and calmodulin, causing increase in cAMP.
LF is a protease that destroys MAPKK –> cell death

Question 9

Differentiate Staph aureus and Staph epi.

Answer 9

aureus: coag +, more virulent, super antigen
epi: coag -, opportunistic (needle drug use)

Question 10

Is S aureus or epi a more common cause of skin infection?

Answer 10

aureus