Pigmented Lesions

Question 1

vitiligo is destruction of melanocytes mediated by what?

Answer 1

the immune system

Question 2

what is happening at the margin of vitiligo lesions?

Answer 2

lymphoproliferation

Question 3

vitiligo is often associated with what other conditions?

Answer 3

autoimmune disorders

thyroid (hypo/hyper)

DM2

Question 4

what is the most common depigmentation disorder of the skin?

Answer 4

vitiligo

1% of gen. pop.

Question 5

what is the epidemiology of vitiligo?

Answer 5

male = female

children=adults

FH in 25-30%

Question 6

what kind of lesion is present in vitiligo?

Answer 6

unpigmented macules (5-50mm) with sharply defined borders

Question 7

what are the 4 types of vitiligo?

Answer 7

generalized

localized

segmental

acral/acrofacial

Question 8

vitiligo often shows _________phenomenon

Answer 8

Koebner’s - lesions at sites of trauma or stress

Question 9

how is the diagnosis of vitiligo typically made?

Answer 9

clinical presentation

may need Woods lamp esp. in lighter skinned individuals

Question 10

the wavelength of a woods lamp is mostly ____ ________the visible spectrum of light

Answer 10

lower than

Question 11

what’s the treatment fo vitiligo?

Answer 11

sun protection is the main treatment

cosmetic coverage

*topical steroids

*phototherapy - kill of proliferation

depigmentation (kill off remaining melanocytes)

surgical grafting - leaves scarring from graft

*active only

Question 12

what kind of phototherapy is used for active vitiligo?

Answer 12

narrow band UVB (311-312 nm)

destroys immune cells attacking melanocytes

stimulates cytokine/gf release which stimulates melanocyte growth

Question 13

what genes are defective in albinism?

Answer 13

the genes that produce melanin

Question 14

What is the gene frequency for albinism?

Answer 14

1 in 70

but it is autosomal recessive

Question 15

what are the two major dermatologic risks of albinism?

Answer 15

sunburn

skin cancer - particularly squamous cell carcinoma

Question 16

what are solar lentigines?

Answer 16

liver spots

localized proliferation of melanocytes and melanization

Question 17

what does the lesion of solar lentigines look like?

Answer 17

hyperpigmented, well-circumscribed lesions

Question 18

what skin types are most at risk for solar lentigines?

Answer 18

Fitzpatrick Types 1-3

Question 19

What two conditions must solar lentigines be distinguished from?

Answer 19

actinic keratosis

lentigo maligna

Question 20

How do you distinguish solar lentigines from pre-malignant or malignant lesions?

Answer 20

warning signs:

rapid growth change

pain

itching

easy or recurrent bleeding

poor healing

Question 21

what is the prevention for solar lentigines?

Answer 21

regular sunscreen use and limiting direct sun exposure

Question 22

what is melasma?

Answer 22

progressive, macular, nonscaling, hypermelanosis of sun-exposed areas of face

Question 23

what is acanthosis nigricans?

Answer 23

dark, hyperkeratotic streaks in skin folds

Question 24

acanthosis nigricans is a common finding in what two types of patients?

Answer 24

diabetic

obese

Question 25

what is post-inflammatory hyperpigmentation?

Answer 25

irregular, darkly pigmented macules and patches at sites of previous injury or inflammation (acne, psoriasis, trauma, lichen planus, etc.)

Question 26

patients with which skin types are most susceptible to post-inflammatory hyperpigmentation?

Answer 26

Skin types IV-VI

Question 27

how long do hyperpigmented lesions last?

Answer 27

months to years

Question 28

what is the treatment of hyperpigmented lesions?

Answer 28

bleaching agents: hydroquinone 3% or azelic acid 20%

not great, hard to control