study guide wk 1

Question 1

Know the significance of desmosomes in skin pathology

Answer 1

hold skin together

Question 2

How do melasma and Vitiligo differ?

Answer 2

Irregular, completely depigmented patches devoid of melanocytes vs. hyperpigmentation on the face

Question 3

What is the fundamental difference between freckles and Lentigo?

Answer 3

freckles: Increased melanin deposition in the basal cell layer of the epidermis Normal number of melanocytes VS. lentigo: localized proliferation of
melanocytes that appear, linear hyperplasia (age spots)

Question 4

What does the word Lentigo mean?

Answer 4

localized proliferation of melanocytes. small,brown, oval. only i basal layer

Question 5

What are the characteristics of congenital birthmarks?

Answer 5

increased melanoma risk, appearance varied….

Question 6

What is meant by the word nevus?

Answer 6

“nest” Benign tumor of melanocytes. junctional,
compound, and intradermal. Uniform tan to brown color
Sharp, well circumscribed borders. Stable. malignancy rare

Question 7

What characteristics indicate that a nevus may be dysplastic?

Answer 7

larger and irregular and may have pigment variation. nevus exhibits cytological and architectural atypia. syndrome inc. melanoma risk

Question 8

Which type of melanoma has the best prognosis, which types have the worse?

Answer 8

best: lentigo maligna melanoma (superficial)
worst:Nodular melanoma (vertical growth)
acral can be bad if not discovered (under nails, dark skinned patiets)

Question 9

What is the most common type of melanoma?

Answer 9

Superficial spreading melanoma

Question 10

In general, how is the malignant potential of melanoma assessed?

Answer 10

Staging is by depth of invasion (vertical
growth)
• Breslow’s thickness
• Clark’s levels

Question 11

What can Acanthosis Nigricans be an indication of?

Answer 11

Thickened, hyperpigmented skin in the axillae and groin–> obesity, hyper-insulinemia (rarely intestinal malignancy)

Question 12

What is the sign of Leser-Trelat?

Answer 12

Seborrheic Keratosis. Leser-Trelat (paraneoplastic

syndrome): sudden development of multiple lesions may accompany an underlying malignancy

Question 13

What is the basic pathophysiology of psoriasis?

Answer 13

Autoimmune disorder accompanied by increased
proliferation and turnover of epidermal keratinocytes
Epidermal hyperplasia (Acanthosis)
• Patchy Hyperkeratinization
• Uniform elongation and thickening of the rete
• Thinning of the epidermis over the dermal papillae
• Munro microabscesses

Question 14

What test is used in the clinic to evaluate for it?

Answer 14

Auspitz sign: capillary bleeding under scale

Question 15

What is the basic pathophysiology of Pemphigus?

Answer 15

autoimmune disorder that is characterized by intraepidermal blister formation. Production of autoantibodies directed against a part of the keratinocyte DESMODOMES called desmoglein 3
results in loss of intercellular adhesions (acantholysis) and blister formation
Intraepidermal acantholysis

Question 16

What test are used in the clinic to evaluate for pemphigus?

Answer 16

Nikolski’s sign, 3 min.

Question 17

What immunoglobulin is involved in the pathogenesis of Dermatitis Herpetiformis, and what disease is the condition thought to be linked to?

Answer 17

Production of IgA antibodies directed against gliadin and other antigens that deposit in the tips of the dermal papillae and result in subepidermal blister formation.
Celiac sprue

Question 18

What is the difference between Xerosis and Eczema (the two look similar)?

Answer 18

Xerosis:cause of pruritus and dry skin in the elderly that is due to decreased skin lipids
Eczema: IgE mediated. characterized by pruritus, causes a vesicular, erythematous rash. Chronic thickenedhyperkeratotic skin

Question 19

What is the basis of the butterfly rash of cutaneous lupus erythematous?

Answer 19

epidermal atrophy with deposition of DNA-anti DNA immune complexes in the basement membrane of the
epidermis–> around nose and cheecks

Question 20

Is Pityriasis Rosea a dangerous condition?

Answer 20

herald patch, christmas tree, maybe virally caused. NOT DANGEOUS

Question 21

What is the difference between Erythema Nodosum and Erythema Multiforme?

Answer 21

Nodosum: raised, erythematous, painful nodules of subcutaneous adipose tissue. SHINS. idiopathic-strep
Multiforme:hypersensitivity skin reaction to infections. vesicles, bullae, and “targetoid” erythematous lesions.
Stevens Johnsons syndrome

Question 22

What is the significance of actinic keratosis?

Answer 22

precursor of squamous cell carcinoma. Sun-induced

dysplasia of the keratinocytes. Bowen disease SCC in situ

Question 23

What layers are involved with the following: BCC, SCC, Melanoma

Answer 23

Basal layer of keratinocytes, SCC in stratum corneum, melanoma in epidermis –> subcutaneous layer (Breslow’s thickness, Clark’s levels)