SKIN PATHOLOGY-1

Question 1

What is Leser-Trélat sign?

Deborah Dalmeida MD

Answer 1

•Paraneoplastic syndrome

Numerous seborrheic keratosis secondary to stimulation of keratinocytes by transforming growth factor-α produced by tumor cells, most commonly carcinomas of the gastrointestinal tract

Deborah Dalmeida MD

Question 2

gray-black patches of verrucous hyperkeratosis on the skin.

mc seen with obesity and insulin resistance

Axilla and neck

Deborah Dalmeida MD

Answer 2

Acanthosis nigricans

Deborah Dalmeida MD

Question 3

List 3 substances that cause urticaria via directly inciting degranulation of mast cells

(Mast cell-dependent, IgE-independent)

Deborah Dalmeida MD

Answer 3

opiates, vancomycin, and radiographic contrast media

Deborah Dalmeida MD

Question 4

What’s the morphologic description of the lesion shown?

Deborah Dalmeida MD

Answer 4

buildup of compacted stratum corneum

Deborah Dalmeida MD

Question 5

Pemphigus /Bullous pemphigoid/ Dermatitis herpetiformis?

Deborah Dalmeida MD

Answer 5

Bullous pemphigoid

[§continuous and linear deposition of IgG along the basement membrane]

Deborah Dalmeida MD

Question 6

IHC Markers for melanoma

Deborah Dalmeida MD

Answer 6

HMB 45, S100

Deborah Dalmeida MD

Question 7

What is the pathogenesis of this condition?

extremely pruritic, bilateral, symmetric and grouped vesicles

responds to a gluten free diet

Deborah Dalmeida MD

Answer 7

anti-gliadin antibodies cross react with reticulin

Deborah Dalmeida MD

Question 8

When do you suspect a melanaoma in a pigmented lesion?

(Hint: The first 5 letters of the english alphabet)

Deborah Dalmeida MD

Answer 8

Asymmetry

irregular Borders

variegated Color

increasing Diameter

Evolution or change over time, especially if rapid

Deborah Dalmeida MD

Question 9

round, flat, coin-like, waxy plaques

stuck on appearance

1. Diagnosis?

2. What does microscopy show?

Deborah Dalmeida MD

Answer 9

1. Seborrheic keratosis
2. small keratin filled cysts- horn cysts

Deborah Dalmeida MD

Question 10

Compare and contrast pemphigus and bullous pemphigoid

Deborah Dalmeida MD

Answer 10

Question 11

See the attached image. Identify the risk factors associated with this condition that worsens on sun exposure

Deborah Dalmeida MD

Answer 11

The condition shown is melasma.

Risk factors include:

1.Pregnancy

2.OCP use

3.Hormone replacement therapy

Deborah Dalmeida MD

Question 12

List 4 causes for the condition described below:

poorly defined, exquisitely tender, erythematous plaques and nodules on the the anterior portion of the shins

Deborah Dalmeida MD

Answer 12

Diagnosis is erythema nodosum.

Causes:

TB, Leprosy

Sulfonamides

Sarcoidosis

Inflammatory bowel disease

Deborah Dalmeida MD

Question 13

Microscopic features of actinic keratosis

Deborah Dalmeida MD

Answer 13

pale bluish appearance (basophilic degeneration) of collagen in the dermis

atypia of the basal cell layer

Deborah Dalmeida MD

Question 14

List 4 risk factors for the tumor shown

Deborah Dalmeida MD

Answer 14

1. exposure to UV light
2. chronic ulcers and draining osteomyelitis
3. old burn scars
4. xeroderma pigmentosum
5. actinic keratoses

Deborah Dalmeida MD

Question 15

1. Identify the lesion described:

Red, itchy rash caused by a substance (poison ivy and nickel in jewelry) that comes into contact with the skin

2. What type of hypersensitivity reaction is this?

Deborah Dalmeida MD

Answer 15

1. Contact dermatitis
2. Type IV

Deborah Dalmeida MD

Question 16

What is rhinophyma?

Deborah Dalmeida MD

Answer 16

Part of Rosacea

Characterised by :permanent thickening of the nasal skin, hypertrophy of sebaceous glands

Deborah Dalmeida MD

Question 17

Compare and contrast Steven Johnson Syndrome with Toxic epidermal necrolysis

Deborah Dalmeida MD

Answer 17

Question 18

1. Diagnosis?
2. Etiology?

Deborah Dalmeida MD

Answer 18

1. Albinism
2. tyrosinase deficiency

Deborah Dalmeida MD

Question 19

elderly

increased in sun exposed areas

Microscopy?

Deborah Dalmeida MD

Answer 19

This is a solar lentigo.

Microscopic feature: linear (nonnested) melanocytic hyperplasia restricted to the cell layer immediately above the basement membrane

Deborah Dalmeida MD

Question 20

Dystrophic nail changes in psoriasis

Deborah Dalmeida MD

Answer 20

1. Nail pitting
2. Onycholysis

Deborah Dalmeida MD

Question 21

Identify the morphologic phase of melanoma from the given description:

horizontal spread of melanoma within the epidermis and superficial dermis

tumor cells seem to lack the capacity to metastasize.

Deborah Dalmeida MD

Answer 21

Radial growth phase

Deborah Dalmeida MD

Question 22

Identify the lesion described:

• well-demarcated, pink to salmon-colored plaque covered by loosely adherent scale that is characteristically silver-white in color
• multiple, minute, bleeding points when the scale is lifted from the plaque - Auspitz sign

Deborah Dalmeida MD

Answer 22

Psoriasis

Deborah Dalmeida MD

Question 23

Histologic hallmark of all types of acute eczematous dermatitis

Deborah Dalmeida MD

Answer 23

Spongiosis

Deborah Dalmeida MD

Question 24

Joint deformity assoc with psoriatic arthritis

Deborah Dalmeida MD

Answer 24

Pencil in cup

Deborah Dalmeida MD

Question 25

List 3 factors involved in the pathogenesis of the condition depicted Deborah Dalmeida MD

Answer 25

1. development of a ***keratin plug*** that blocks outflow of sebum to the skin surface 2. ***hypertrophy of sebaceous glands*** during puberty under the influence of ***androgens*** 3. lipase-synthesizing bacteria ***(Cutibacterium acnes)*** Deborah Dalmeida MD

Question 26

1. List 4 causes for the lesion shown 2. What ype of hypersensitivity reaction does it represent? Deborah Dalmeida MD

Answer 26

1. Herpes simplex, mycoplasma Sulfonamides Malignant disease Collagen vascular disease 2. Type 4 hypersensitivity reaction Deborah Dalmeida MD

Question 27

Pemphigus /Bullous pemphigoid/ Dermatitis herpetiformis? Deborah Dalmeida MD

Answer 27

Pemphigus [deposition of immunoglobulin along the plasma membranes of epidermal keratinocytes in a reticular or fishnet-like pattern.] Deborah Dalmeida MD

Question 28

Pemphigus /Bullous pemphigoid/ Dermatitis herpetiformis? Deborah Dalmeida MD

Answer 28

Dermatitis herpetiformis [discontinuous, granular deposits of lgA selectively localized in the tips of dermal papillae] Deborah Dalmeida MD

Question 29

Identify the condition characterised by the eosinophilic inclusions shown. What are they called and what do they represent? Deborah Dalmeida MD

Answer 29

Lichen planus Civatte (Colloid bodies)/apoptotic keratinocytes Deborah Dalmeida MD

Question 30

Potential marker or precursor of melanoma Deborah Dalmeida MD

Answer 30

Dypslastic nevus Deborah Dalmeida MD

Question 31

List 4 histopathologic features of psoriasis Deborah Dalmeida MD

Answer 31

Acanthosis Parakeratosis Hypogranulosis/absent granular layer Munro microabscess Deborah Dalmeida MD

Question 32

**What is the infectious condition associated with the lesion described?** multiple, symmetric , itchy, violaceous, flat-topped papules on the wrist and elbows Wickham striae Deborah Dalmeida MD

Answer 32

Th lesion described is Lichen planus. The infectious condition assoc with it is HCV induced chronic hepatitis Deborah Dalmeida MD

Question 33

tan to brown, _uniformly_ _pigmented_, small macules to papules with well-defined, rounded borders Microscopy: aggregates or nests of round cells that grow along the dermoepidermal junction Deborah Dalmeida MD

Answer 33

Junctional nevus Deborah Dalmeida MD

Question 34

**1. Identify the tumor described:** Location: Inner canthus eye Clinical presentation: Pearly papule with telangiectasias **2. What kind of an ulcer can this lesion exhibit?**

Answer 34

1. Basal cell carcinoma 2. Rodent ulcer

Question 35

List 3 histopathologic features seen in the attached image. Which condition is it associated with?

Answer 35

1. a. Hyperkeratosis b. Hypergranulosis c. Saw tooth appearance of rete ridges d. Band like lymphocytic infiltrate 2. Lichen planus

Question 36

**Identify the morphologic phase of melanoma from the given description:** appearance of a nodule correlates with the emergence of a clone of cells with metastatic potential

Answer 36

Vertical growth phase

Question 37

Middle aged female erythematous papules and pustules over the face Flushing episodes exacerbated by spicy food/ alcohol/stress

Answer 37

Rosacea

Question 38

I) Identify this Skin malignancy a. See attached image b. HMB 45 , S100 positive II) What are the 2 mutations assoc with this tumor?

Answer 38

i) Malignant melanoma ii) loss of **p16/INK4a** and activating mutations in **BRAF**

Question 39

How do freckles differ from lentigo, morphologically?

Answer 39

**Freckles:** _normal number_ of melanocytes with ↑ melanin pigment **Lentigo:** linear (nonnested) melanocytic hyperplasia *(which means melanocytes are increased in number)*

Question 40

Hyperkeratotic, pearly gray-white **sandpaper** consistency Can lead to squamous cell carcinoma of skin

Answer 40

Actinic keratosis

Question 41

1. Identify the lesion indicated by the white arrow 2. What's the cause?

Answer 41

1. Senile purpura ## Footnote 2. ↑X-linking collagen/elastic tissue → fragile vessels → Senile purpura

Question 42

Dermatologic condition resulting from localized mast cell degranulation and resultant dermal microvascular hyperpermeability Wheals present

Answer 42

Urticaria

Question 43

1. Etiology? 2. Which investigation highlights the depigmented areas?

Answer 43

1. Autoimmune 2. Woods Lamp

Question 44

Identify the lesion described: ## Footnote cords and islands of variably basophilic cells with hyperchromatic nuclei; tumor cells at the periphery of the island exhibit palisading; retraction artifacts

Answer 44

Basal cell carcinoma

Question 45

What are the two scales used to determine the depth of invasion in malignant melanoma

Answer 45

1. Breslow Index 2. Clark’s levels of invasion