Laboratory Diagnostics of Dermatological Lesions and Disorders

Question 1

__ are indicated when the cause of a skin lesion or disease is not obvious from history and physical examination alone

Answer 1

diagnostic tests

Question 2

oblique lighting is also known as __

Answer 2

side lightening

Question 3

KOH stain is normally used for __

Answer 3

fungus

Question 4

Gram stain is used for __

Answer 4

shape of organism

Question 5

Tzank smear is used for __

Answer 5

herpes

Question 6

oil immersion is used for __

Answer 6

research setting and to look at bacteria

Question 7

special techniques for diagnostics

just read over these!

Answer 7

Magnification with a hand lens
Oblique lighting
Microscopy
 - KOH
 - Gram stain
 - Tzank Smear
 - Oil immersion
Diascopy
Dermoscopy
Skin biopsy
Wood's lamp
Patch Test

Question 8

allows you to get a closer look at enhanced morphologic detail

Answer 8

magnification with a hand lens

Question 9

4 types of microscopy

Answer 9

KOH
Gram stain
Tzank Smear
Oil immersion

Question 10

__ solution dropped onto a slice with a thin layer of specium sample ie scraping, discharge

Answer 10

KOH

Question 11

2 drops of 10% to 20% KOH and let it dry for several minutes purpose is ____

Answer 11

dissolve the keratin of the fungal elements

Question 12

__ dissolves epithelial cells to reveal hyphae, with their characteristic branching pattern, to increase the likelihood of detecting hyphae on microscopic exam of skin scraping, begin with a low light and low power

Answer 12

KOH

Question 13

If fungal elements are not detected and clinical suspicion of tinea is high, consider arranging for a ___

Answer 13

fungal culture

Question 14

the differentiate between gram positive and gram negative organisms, while simultaneously learning about the cellular morphology and arrangement

Answer 14

gram stain

Question 15

___ cells have a thick peptidoglycan cell wall that is able to retain the crystal violet-iodine complex that occurs during staining

Answer 15

gram positive

Question 16

__ cells have only a thin layer of peptidoglycan

Answer 16

gram negative

Question 17

__ cells will appear blue - purple

Answer 17

gram positive

Question 18

__ cells will appear pink - red

Answer 18

gram negative

Question 19

what solution washes the violet off and allows the red stain to absorb?

Answer 19

ETOH solution

Question 20

how long does it take for fungal cultures to come back?

Answer 20

weeks to months

Question 21

how long does it take for bacterial cultures to come back?

Answer 21

24-48 hours

( SIDE NOTE: 24 hours you get a preliminary report and then at 48 hours you receive a final report. )

Question 22

woods light

Answer 22

360-nm light source used in localizing the
site of melanin in Caucasian skin,
diagnosing infection and porphyria.

Question 23

woods light is useful in

Answer 23

diagnosing disorders of pigmentation:
Vitiligo: completely white
Erythasma: coral red
Porphyria cutanea tarda: Dark pink urine
Pseudomonas infection of skin: pale bluegreen
Dermatophytes: yellow-green
Tinea versicolor: dull yellow

Question 24

slide #33 is a case study pic w/ woods lamp

Answer 24

i think dr. butler said this appearance was due to just regular, NL sun exposure in everyday life