Histopath - Skin Pathology

Question 1

What are the 3 broad layers of skin?

Answer 1

Epidermis
Dermis
Subdermis

Question 2

What are the 5 layers of the epidermis?

Answer 2

Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale

(Corn Lovers Grow Some Bales lol)

Question 3

What are the main cells of the epidermis?

Answer 3

Keratinocytes

Question 4

How do the keratinocytes move through the epidermis?

Answer 4

From the stratum basale, upwards to the corneum where they shed off and are renewed every 15-30 days

Question 5

What can be found in the dermis?

Answer 5

Collagen
Elastin fibres
Eccrine swear glands
Sebaceous glands
Hair follicles
+ highly vascular

Question 6

Function of subcutaneous tissue

Answer 6

Fatty tissue acts as shock absorber

Question 7

What is hyperkeratosis?

Answer 7

Increase in S. corneum / increased keratin

Question 8

What is parakeratosis?

Answer 8

Thickening of skin due to scratching as a result of abnormal retention of nuclei in the stratum corneum

Question 9

What is acanthosis?

Answer 9

Increase in stratum spinosum layer

Question 10

What is acantholysis?

Answer 10

Decreased cohesions between keratinocytes

Question 11

What is spongiosis?

Answer 11

Intercellular oedema between keratinocytes

Question 12

What is lentiginous?

Answer 12

Linear pattern of melanocyte proliferation within stratum basale

Question 13

What would you see in vesiculobullous lesions?

Answer 13

Bullae

Question 14

What would you see in spongiotic lesions?

Answer 14

Oedema

Question 15

What would you see in psoriaform lesions?

Answer 15

Thickened skin

Question 16

What would you see in lichenoid lesions?

Answer 16

Sheeny plaque

Question 17

What is the presentation of eczema/dermatitis?

Answer 17

Inflamed, dry itchy rashes

Question 18

Acute histology of eczema/dermatitis

Answer 18

Spongiosis, inflammatory infiltrate in dermis, dilated dermal capillaries

Question 19

Chronic histology of eczema/dermatitis

Answer 19

Acanthosis, hyperparakeratosis, crusting, scaling

Question 20

What is presentation of psoriasis?

Answer 20

Well demarcated pink scaly plaques

Question 21

Histology of psoriasis

Answer 21

Parakeratosis, loss of stratum granulosum

Question 22

4 types of bullous diseases

Answer 22

1. Dermatitis herpetiformis
2. Bullous pemphigoid
3. Pemphigus vulgaris
4. Pemphigus foeliaceus

Question 23

What is dermatitis herpetiformis associated with?

Answer 23

Coeliac

Question 24

Pathophysiology of dermatitis herpetiformis

Answer 24

IgA Abs bind to basement membrane -> subepidermal bulla

Question 25

Clinical features of dermatitis herpetiformis

Answer 25

Itchy vesicles on extensor surfaces of elbows, buttocks

Question 26

Histology of dermatitis herpetiformis

Answer 26

Microabscesses Subepidermal bullae Neutrophil & IgA deposits

Question 27

Pathophysiology of Bullous pemphigoid

Answer 27

IgG Abs bind to hemidesmosomes of basement membrane -\> subepidermal bulla

Question 28

Clinical features of Bullous pemphigoid

Answer 28

Large tense bullae on erythematous base

Question 29

Histology of Bullous pemphigoid

Answer 29

Subepidermal bulla with eosinophils Linear deposition of IgG along basement membrane

Question 30

Pathophysiology of Pemphigus vulgaris

Answer 30

IgG Abs bind to demosome proteins 1,3 -\> intraepidermal bulla

Question 31

Clinical features of Pemphigus vulgaris

Answer 31

Easily ruptured (red, raw) flaccid blisters

Question 32

Histology of Pemphigus vulgaris

Answer 32

Intraepidermal bulla Netlike pattern of intercellular IgG deposits

Question 33

Pathophysiology of Pemphigus foliaceus

Answer 33

IgG Ab against desmoglein 1 attacks outer layer of keratinocytes on stratum corneum

Question 34

Clinical features of Pemphigus foliaceus

Answer 34

V rare No intact bullae Appears excoriated

Question 35

Histology of Pemphigus foliaceus

Answer 35

3 levels of split

Question 36

3 types of skin cancers

Answer 36

1. Squamous cell carcinoma 2. Basal cell carcinoma 3. Melanoma

Question 37

Most common kind of skin cancer

Answer 37

BCC

Question 38

What is the pre-malignant stage of SCC called?

Answer 38

Bowen's disease

Question 39

When does SCC become malignant?

Answer 39

Once it has invaded basement membrane

Question 40

Clinical feature of SCC

Answer 40

Ulcerates

Question 41

Clinical feature of BCC

Answer 41

Pearly-rolled edge, often with telangiectasia

Question 42

What are benign melanocytic lesions called?

Answer 42

Naevi/moles

Question 43

Histology of malignat melanoma

Answer 43

Atypical melanocytes - initially growing horizontally in epidermis (radial growth phase), then vertical growth into dermis

Question 44

What is the staging system used for prognosis of malignant melanomas?

Answer 44

Breslow thickness