19.2: Blistering Dermatoses

Question 1

What is the pathophysiology of pemphigus vulgaris?

Answer 1

-Autoimmune destruction of desmosomes

Question 2

What type of immunoglobin is involved in pemphigus vulgaris? What protein is it directed against?

Answer 2

IgG against desmoglein

Question 3

What is the IF staining pattern associated with pemphigus vulgaris?

Answer 3

IgG surrounding keratinocytes in a “fish net” pattern

Question 4

Fishnet pattern on IF stain of epidermis = ?

Answer 4

Pemphigus vulgaris

Question 5

What is the protein that holds together epidermal cells?

Answer 5

Desmosomes, formed of desmoglein

Question 6

What is the protein that holds the epidermis to the BM?

Answer 6

Hemidesmosomes

Question 7

In what layer of the skin do blisters from pemphigus vulgaris form?

Answer 7

Epidermis–specifically the stratum spinosum detaches

Question 8

Why is it that the blisters with pemphigus vulgaris rupture easily?

Answer 8

Only a partial, thin layer of epidermis comprises the blister

Question 9

Which involves the skin and oral mucosa: pemphigus vulgaris or bullous pemphigoid

Answer 9

Pemphigus vulgaris

Question 10

What is the pathophysiology of bullous pemphigoid?

Answer 10

Autoimmune attack against the hemidesmosomes

Question 11

What is the antibody class that is implicated with bullous pemphigoid? What is it directed against?

Answer 11

IgG against the BM

Question 12

How does bullous pemphigoid present?

Answer 12

Tense subepidermal blisters of the skin with oral mucosa sparing

Question 13

Which has tense bullae, and which has flaccid bullae: bullous pemphigoid; pemphigus vulgaris

Answer 13

Tense = bullous pemphigoid

Flaccid = Pemphigus vulgaris

Question 14

In what skin layer do the blisters with bullous pemphigoid form?

Answer 14

between the dermis and the epidermis

Question 15

What are the IF findings of bullous pemphigoid?

Answer 15

Linear IgG antibodies along the BM

Question 16

Why are the bullae tense and hard to rupture with bullous pemphigoid?

Answer 16

Whole epidermis is present in the wall of the blister

Question 17

What is dermatitis herpetiformis?

Answer 17

-Autoimmune deposition of IgA at the tips of the dermal papillae (“just the tips”)

Question 18

What type of immunoglobin is implicated in the pathogenesis of dermatitis herpetiformis? What are these directed against?

Answer 18

• IgA

- Ab against gluten

Question 19

What GI disease is associated with dermatitis herpetiformis?

Answer 19

Celiac Sprue

Question 20

What is the treatment for dermatitis herpetiformis?

Answer 20

Gluten control

Question 21

What is erythema multiforme, and what are the skin characteristic of this disease?

Answer 21

-HSR with targetoid rash and bullae

Question 22

targetoid rash and bullae = ?

Answer 22

Erythema multiforme

Question 23

What infectious disease is associated with erythema multiforme?

Answer 23

HSV

Question 24

Erythema multiforme with oral mucosal involvement and fever is what?

Answer 24

Steven-Johnson’s syndrome

Question 25

What is toxic epidermal necrolysis?

Answer 25

Severe form of SJS

Question 26

What, generally, is SJS?

Answer 26

Diffuse sloughing of skin resembling a large burn

Question 27

What usually causes SJS?

Answer 27

Adverse drug reaction

Question 28

What is the antiepileptic agent that classically is associated with SJS?

Answer 28

Lamotrigine