Skin and Soft Tissue

Question 1

What are the 4 classic presentations of an SSTI?

Answer 1

1-Rubor (erythema)
2-Calor (warmth)
3-Tumor (edema/swelling)
4-Dolor (tenderness)

Question 2

What term is described as a crackling or the feeling of rice krispys under a tissue?

Answer 2

Crepitus

*often gas gangrene

Question 3

Rebound of a furuncle is called what?

Answer 3

Fluctuance

Question 4

Bruising can be called?

Answer 4

Purpura

Question 5

Another word for blisters is?

Answer 5

Bullae

Question 6

Folliculitis is a minor infection associated with friction and sweat gland activity and is caused by what?

Answer 6

• Staph aureus
• Hot tub folliculitis is pseudomonas aeruginosa

*treated with soap and water and topical antibiotics

Question 7

Acne is inflammation of hair follicle and associated sebaceous gland and is caused by what?

Answer 7

Propionibacterium acnes as well as hormonal influences

Question 8

Pus is comprised of what?

Answer 8

WBC’s accumulation and cellular debris

Question 9

A fluctuant, tender, erythematous nodule with surround erythema that results from the nacres/liquefying of tissue is likely what?

Answer 9

Soft tissue abscess

*often polymicrobial but staph aureus most common. Treated by incision and drainage, maybe systemic antibiotics

Question 10

Multiple furuncles (boils) congregate to form what?

Answer 10

Carbuncle

*infection spreads to subcutaneous tissue, usually s. aureus, treated by I and D

Question 11

“Ringworm” is really a yeast infection in the keratinized layers cause by what?

Answer 11

Dermatophyte fungi

Question 12

What are the 3 most common causes of body skin yeast infections?

Answer 12

1-Trichophyton
2-Microsporum
3-Epidermophyton

*Candida albicans is most common vaginal

Question 13

Impetigo has characteristic honey crusts, is highly contagious, is in the epidermis and is caused by what?

Answer 13

Group A strep or Staph aureus

Question 14

Erysipelas is a deep dermis infection with rubor, calor, tumor and dolor and is caused by what?

Answer 14

Group A strep

*treat with penicillin usually

Question 15

Cellulitis is caused by group A strep or staph Aureus and effects primarily what skin layer?

Answer 15

Subcutaneous tissue

Question 16

“Flesh eating” Group A strep or S. aureus that cause a rapid extension of infection are referred to as?

Answer 16

Necrotizing fasciitis

*able to digest fascial barriers. many times polymicrobial with G (+) and anaerobes

Question 17

Which anaerobe has spores and can cause necrotizing fasciitis?

Answer 17

Clostridium perfringens

Question 18

Polymicrobial infection of the genitals and perineum is referred to as?

Answer 18

Fournier’s gangrene

*a necrotizing fasciitis

Question 19

Poor circulation near a wound is optimal for what organisms?

Answer 19

Anaerobes

Question 20

What potential pathogen is the all-time champ, is acute, aggressive, causes locally destructive purulent lesions, and colonizes anterior nares in 10-30% of the population?

Answer 20

Staphylococcus Aureus

*gram (+) cocci

Question 21

Alpha-toxin of S. Aureus causes what?

Answer 21

Scalded skin syndrome

Question 22

A problem in super absorbent tampons or sinus surgeries if the dressings are not changed frequently, TSST-1 is an S aureus toxin that causes what?

Answer 22

Staph toxic shock syndrome

Question 23

What does the staph exotoxin do in the GI tract?

Answer 23

Acts as an enterotoxin and causes staphylococcal food poisoning

Question 24

What gene is required for MRSA strains?

Answer 24

mecA gene (makes new PBP with reduced affinity for B-lactams)

Question 25

What are the drugs of choice for MSSA?

Answer 25

• Anti-staph pcn (nafcillin, oxacillin)

- cephalosporins

Question 26

With higher risk in crowded living, skin-skin contact, poor hygiene and IV drug users, what is the treatment for MRSA?

Answer 26

• Trimethoprim-sulfa
• doxycycline
• vancomycin,
• linezolid
• daptomycin

Question 27

What are two sequelae of Group A strep (strep pyogenes)?

Answer 27

• Rheumatic fever after pharyngitis

- Post-strep glomerulonephritis after pharyngitis

Question 28

Which Strep exotoxins can act as super antigens?

Answer 28

Exotoxins A and B

Question 29

Which strep exotoxins are cytotoxic and lyse leukocytes, tissue cells and platelets?

Answer 29

Streptolysins O and S

Question 30

What are three strep inflammatory enzymes?

Answer 30

1-Streptokinase (protease)
2-Hyaluronidase (degrades carbohydrate)
3-DNase

Question 31

What anaerobic, spore-forming, gram-positive rod with square ends is found in soil and human colon and produces hydrogen, CO2 gases and exotoxins?

Answer 31

Clostridium perfringens

*can result in gas gangrene. more typical in crushing injuries where blood flow is decreased

Question 32

What gram negative rod is associated with animal bites?

Answer 32

Pasteurella multocida

Question 33

What gram negative rod is a prototypical non-fermenter, is an environmental pathogen and causes hot tub folliculitis or infection after burns?

Answer 33

Pseudomonas aeruginosa

Question 34

What gram negative rod is in salt-water environments (shellfish) causes fever, sepsis and hemorrhagic bullae and is associated with iron overload (cirrhosis)?

Answer 34

Vibrio Vulnificus

Question 35

A mycetoma of “Madura foot” is caused by what?

Answer 35

• Bacterial actinomyces or nocardia

- Fungal

Question 36

“Rose gardeners thumb” presents usually as erythematous furuncles up the lymph chain and is caused by what?

Answer 36

Sporothrix schenckii

*Called sporotrichosis

Question 37

What is the best specimen when trying to diagnose an SSTi?

Answer 37

Pus or fluid from the infection

Question 38

When the abscess is in the skin think?

Answer 38

Staph aureus

Question 39

When the abscess is in the mouth/rectum/vagina think?

Answer 39

Polymicrobial

Question 40

With Cellulitis and erysipelas think?

Answer 40

Strep Pyogenes (group A strep)