The Skin

Question 1

Seconday lesion

Answer 1

evolves from pirmary skin lesion, (i.e crust of chicken pox) or can be because of scratching or infection

Question 2

distribution

Answer 2

refers to where on the body the lesions are found (e.g., hands, face, trunk, flexor or extensor surfaces).

Question 3

3 layers of skin

Answer 3

1. epidermis
2. dermis
3. subcutaneous

Question 4

vellus hair

Answer 4

short, fine, inconspicuous and usually unpigmented (peach fuzz).

Question 5

terminal hair

Answer 5

Terminal hair – coarser, thicker and pigmented. Example: - scalp, eyebrows, pubic region.

Question 6

Three phases of hair

Answer 6

Catagen phase – transitional phase – 3%
Telogen phase – resting phase – 10-15%
Anagen phase – Growing phase – 85-90%

Question 7

clubbing of nails

Answer 7

rounding of the nail, soft and spongy

Etiologies: 
Congenital  
****Chronic hypoxia*** (i.e. ventricular, septal defect, severe COPD)
Heart disease
Lung cancer
Hepatic cirrhosis

_ people are also ashen appearing and cyanotic

Question 8

Psoriasis

Answer 8

• small pits in the nails, may be due to cirrohsis

Question 9

Mee’s lines

Answer 9

discolored lines, due to traumatic event such as illness or metabolic event

Question 10

Beau’s lines

Answer 10

interruption of growth of nail, appears as an indent

- may follow surgery or metabolic illness

Question 11

what causes color in skin? brown, yellow, red, blue?

Answer 11

brown: melanin
yellow: carotene, bilirubin (jaundice)
red: carboxyhemoglobin (CO poisoning), polycythemia (increased RBC counts)

bluish-red: de-oxyhemoglobin (cyanosis)

Question 12

melanocytes

Answer 12

cells containing melanin in organelles called melanosomes. The cells migrate outward to the epidermis.

• albinos: melanin is absent

Question 13

mobility and turgor

Answer 13

not ease with which skin lifts up - mobility

- note speed which which it returns to place (turgor)

Question 14

important flexor surfaces?

Answer 14

back of knees, back of neck, back of elbows

- atopic dermatitis is seen here

Question 15

extensory surface

Answer 15

extensors of elbow and knee

• cirrihosis
• syphillis (palms of hands)

Question 16

macule

Answer 16

small flat spot, less than 1.0 cm

• benign, loss of melanocytes, not much for treatments
  i. e Vitiligo

Question 17

patch

Answer 17

flat spot or lesion greater than 1.0 cm

i.e. cafe-au-lait spots, looks like little stains of coffee (associated with tumerosclerosis)

Question 18

papule

Answer 18

raised lesion up to 1.0 cm, reddened

i.e. psoriasis

Question 19

plaque

Answer 19

raised lesion greater than 1.0 cm

i.e. psoriasis

Question 20

nodule

Answer 20

firm, hard lesion, deeper than a papule, less than 1/2 cm

Question 21

cyst

Answer 21

nodule filled with material, liquid or semi-solid - often encapsulated

i.e. inclusion cyst on face, caused by blocked sebaceous gland

Question 22

vesicles

Answer 22

fluid filled lesions, less than 1.0 cm
- single or in clusters

i.e. herpes zoster virus, found in dermatome skin patches

Question 23

bulla

Answer 23

fluid filled lesion greater than 1.0 cm

i.e. insect bite

Question 24

wheal

Answer 24

superficial localized area of skin, blanche with pressure
* these are vascular lesions*

i.e. urticaria

Question 25

pustule

Answer 25

open lesions filled with pus

i.e. acne

Question 26

scale

Answer 26

flaking of dead exfoliated epidermis

Question 27

crust

Answer 27

dried residue of skin exudates such as serum, pus or blood

i.e. impetigo (responds to systemic antibiotics)

Question 28

lichenification

Answer 28

thickening of skin from rubbing or scratching

• often seen in flexing

Question 29

excoriation

Answer 29

linear erosions caused by scratching

• Koebner phenomena: skin trauma from scratching may cause new lesions - i.e. spreading of poison oak from scratching

Question 30

fissure

Answer 30

linear crack in skin

i.e. tinea pedis

Question 31

ulcer

Answer 31

a deeper loss of dermis

Question 32

patterns/different shapes?

Answer 32

linear 
cluster 
geographic (irregular)
serpiginous
heliotrope = around eyes
annular

Question 33

what is KOH used for?

Answer 33

use for looking for yeast infections (KOH destroys skin and you see the yeast cells)

Question 34

gram staining

Answer 34

looking for bacteria
- used for pustule

chains of + cocci = staph
bunches of + cocci = strep

Question 35

Tzanck smear

Answer 35

used to look for herpes - will see multi-nucleated giant cells

Question 36

Oil mount

Answer 36

used for looking for Scabei mite from skin scraping

- used for looking for parasites

Question 37

Basal Cell Carcinoma

Answer 37

• 80% of the skin cancers
• Arise from the basal layer of the epidermis
• Grow slowly, rarely metastasize
• “rodent ulcer”
• curable

Pearl white, domed shaped papule with telangiectasias.
Center can ulcerate, “rodent ulcer”.

Question 38

Squamous cell Carcinoma

Answer 38

• 16% of the skin cancers
• Arise from the upper layer of the epidermis
• Can metastasize if left untreated
• more aggressive, treated with simple excision
• can look crusty and scaley, not pearly
• Commonly found on head, neck or hands.
  May develop from a precursor actinic keratoses

Question 39

malignant melanoma

Answer 39

• 4% of the skin cancers
• Arise from melanocytes
• Can spread rapidly and metastasize, any organ, including the brain and heart
• Can have high mortality rates
• Risk, 1 in 90
• Fair skinned at higher risk, excessive sun exposure
• May require deforming surgery

Question 40

ABCDE screening for melanoma

Answer 40

Asymmetry
irregular borders: ragged, notched or blurred
color, especially blue or black
Diameter: greater than 6 mm of different from others, especially changing, itching or bleeding
Elevation or enlargment