Evaluation of Skin Disorders

Question 1

What does blanching indicate when using diascopy?

Answer 1

Blanching of blue to red lesions followed by gradual refilling indicates blood in the capillaries.

Absence of blanching indicates blood leaching outside of the capillaries, as in petechiae.

Question 2

A Gram Stain is used to determine….

Answer 2

Determines gram-positive vs. gram-negative

Question 3

A Tzanck test is used for what types of organisms?

Answer 3

Reveals multinucleated giant cells typical of herpes simplex or varicella-zoster viruses.

The top vesicle must be removed to obtain fresh fluid from the base of the lesion.

Question 4

KOH is used to determined what types of organisms?

Answer 4

Determines:
Hyphae and spores consistent with candidiasis.

Spaghetti and meatball appearance of tinea versicolor

Question 5

Cultures can identify what type of organisms?

Answer 5

Herpesvirus, Streptococcus, Staphylococcus or Pseudomonas require removal of the outer crust or cuticle of the lesion to obtain fluid for culture.

Question 6

How do you obtain a scabies preparation?

Answer 6

Superficial skin shaving from a skinfold area obtained from the top of a burrow and examined under oil immersion.

Question 7

What does dermoscopy reveal?

Answer 7

Changes in pigmentation. ie: melanoma

Can determine if borders are regular vs. irregular.