Microbiology: Random + Not in Sketchy

Question 1

Virulence factor in Staph Aureus that contributes to skin infections

Answer 1

Panton-Valentine leukocidin (PVL)

- Forms pores in neutrophil membranes → lysis

Question 2

Associated with folliculitis via hot tubs, whirlpools, swimming pools, etc.

Answer 2

Pseudomonas aeruginosa

Question 3

Honey-colored crusts is known as ______ and associated with two different bugs

Answer 3

Impetigo, Strep Pyo and Staph Aureus (not in sketchy)

Question 4

Orange peel appearance is known as ________ and associated with this bug

Answer 4

Erysipelas (a form of cellulitis), usually Strep pyogenes

Question 5

Weird characteristic of the bullae seen in SSSS

Answer 5

Staphyloccocal scalded skin syndrome via superantigen exfoliative toxins: Bullae lacks bugs and leukocytes.

Question 6

SSSS bullae have positive ______ sign

Answer 6

Nikolsky sign: Light rubbing of skin results in exfoliative of epidermis due to epidermal/dermal dissociation. (which means it attacks the desmosomes…?)

Question 7

Large eosinophilic cytoplasmic inclusions in affected superficial epithelial cells are associated with _______ virus and are called ________

Answer 7

Molluscum Contagiosum Virus (MCV, part of Pox Virus family)

- Brick-shaped (dumb bell shaped in sketchy micro)

Question 8

What is a herald patch and what is it associated with? (two different organisms technically)

Answer 8

Herald patch is a single round or oval, 2.5 cm diam, that eventually becomes scaly and clears centrally (collarette of scale (important)). It is associated with Tinea Corporis or Pityriasis Rosea (HHV-6, 7, or 8)

• KOH test to rule out fungi

Question 9

What does the triad of Herald Patch, Christmas Tree Distribution, and absence of symptoms except possible mild pruritus refer to?

Answer 9

Pityriasis Rosea

- Note: Christmas tree distribution = long axis of oval plaques oriented along skin lines.

Question 10

Wood’s Lamp: Blue Green

Answer 10

Microsporidium (Tinea capitus)

Question 11

Wood’s Lamp: Coral Red

Answer 11

Cornyebacterium erythematous

- erythracsma

Question 12

Wood’s Lamp: Pink or Orange

Answer 12

Porphyria Cutanea Tarda

Question 13

Onychomycosis = major bug

Answer 13

dermatophyte trichophyton

- candida can also do it.

Question 14

dermatophyte test media

Answer 14

yellow-phenol indicator in media and turns red when dermatophyte is present (2-4 weeks)