Clinical Microbiology HW#11

Chapter 21

1. All of the following are protective factors of the skin and its secretions EXCEPT

pyocyanin production

protective factors of the skin and its secretion:

lysozyme production.

salt.

tightly packed cells.

keratin.

2. Which region of the skin supports the largest bacterial population?

Armpits

3. An eight-year-old girl has scabs and pus-filled vesicles on her face and throat. Three weeks earlier she had visited her grandmother, who had shingles. What infection does the eight-year-old have?

Chickenpox

4. All of the following are characteristic of Pseudomonas aeruginosa EXCEPT

gram-positive cell wall

Characteristics of Pseudomonas aeruginosa:

growth in moist environments

rod-shaped

resistance to many types of disinfectants and antibiotics

production of pyocyanin

5. Koplik spots are a diagnostic indicator of

Measles

6. Thrush and vaginitis are caused by

Candida albicans

7. All of the following are characteristic of the Group A beta-hemolytic streptococci EXCEPT

methicillin resistance

Characteristic of the Group A beta-hemolytic streptococci:

the ability to damage cell membranes

the ability to dissolve blood clots

hyaluronidase production

M proteins

8. Exfoliative toxin is responsible for

scalded skin syndrome

9. The eradication of smallpox was possible because

there are no animal reservoirs of the virus

10. Which of the following leads to all the others?

staphylococcal infection

11. The patient has a papular rash. Microscopic examination of skin scrapings reveals small eight-legged animals. The etiology is

Sarcoptes

12. The patient has vesicles and scabs over her forehead. Microscopic examination of skin scrapings shows gram-positive cocci in clusters. The etiology is

Staphylococcus aureus

13. A 35-year-old woman has a red, raised rash on the inside of her thighs. Gram-stained skin scrapings show large budding cells with pseudohyphae. The infection is caused by

Candida albicans

14. Which of the following is likely to spread MRSA among athletes?

All of the following: taping gels; whirlpool baths; shared equipment; physical contact

15. The majority of the staphylococci isolated from human skin are coagulase-positive

FALSE

16. The abbreviation GAS refers to pathogenic strains of Staphylococcus

FALSE – streptococci

17. Candidiasis often occurs following antibiotic therapy for bacterial infections

TRUE

18. Newborns' eyes are treated with an antibiotic

as a routine precaution

19. Acanthamoeba infections are usually transmitted via insects

FALSE

Chapter 21 Reading Question

1. You have a culture of bacteria that you suspect is either Staphylococcus aureus or Streptococcus pyogenes. Is there any morphological difference between the two?

Yes. S. aureus tends to grow in clusters, whereas S. pyogenes tends to grow in chains.