Subepidermal Vesiculobullous Dermatitis

Question 1

Subepidermal Vesiculobullous Dermatitis

DDX

Answer 1

1. Bullous pemphigoid
2. Dermatitis herpetiformis
3. Epidermolysis bullosa acquisita (EBA)
4. Porphyria cutanea tarda

Question 2

Bullous pemphigoid (BP)

Clinical

Histology

DDX

DIF

Answer 2

Clinical: older pts with itchy, tense vesicles/bullae on flexor surfaces

Histology:

1. Eos in papillary dermis and along DE junction

DDX: bullous drug, EBA

DIF: linear basement membrane deposition of IgG and C3

Question 3

Dermatitis herpetiformis

Clinical

Histology

DIF

DDX

Answer 3

Clinical: younger adults with h/o celiac; grouped vesicles on extensors

Histology:

1. Neutrophils +/- eos in papillary dermal tips
2. subepidermal split may be subtle

DIF: Papillary dermal deposition of IgA

DDX:

1. Linear IgA bullous dermatosis (need DIF to distinguish)
2. Bullous lupus

Question 4

Epidermolysis bullosa acquisita

Clinical

Histology

Answer 4

Clinical: adults with autoummune diseases, noninflammatory bullae on extensors

Histology:

1. pauci-inflammatory blister with few lymphs
2. rare inflammatory bullae with neuts
3. few eos

Question 5

Porphyria cutanea tarda

Site

Histology

Answer 5

Acral sites

Histology:

1. Cell-poor blister
2. Festooning (dermal papillae preserved)
3. Caterpillar bodies