Blisters

Question 1

What are the major bullous diseases

Answer 1

Pemphigus foliaceous: all ages, red/crusting, few fragile blisters, can be associated with SLE (pemphigus erythematosus), can be drug induced

Pemphigus: elderly, oral lesions, esophageal erosions, flaccid blisters, non-itchy, + Nikolsky’s, paraneoplastic variant

Cicatricial pemphigoid: elderly, itch, oral and eye involvement, few tense blisters on face and neck, heals with scar

Pemphigoid: elderly, itchy, uritcarial plaques, tense blisters, palms and soles

Dermatitis herpetiformis: middle age, very itchy, gluten-sensitive enteropathy, small bowel lymphoma

Question 2

What diseases target the granular layer

Answer 2

Bullous ichthyosiform erythroderma

pemphigus foliaceus and erythematosus

Question 3

What diseases target the upper and mid spinous layer

Answer 3

Dermatophyte infxn
Dyshidrosis
eczematous blister
friction blister
insect bite and scabies
miliaria rubra
viral blisters

Question 4

What diseases target the basal layer

Answer 4

Erythema multiforme (epidermal type)
Epidermolysis bullosa simplex
fixed drug eruption
kerosene necrosis
lichen planus
TEN

Question 5

What diseases target the lamina lucida layer

Answer 5

BP
Cicatricial pemphigoid
DH
Epidermolysis bullosa acquisita/letalis
herpes gestationis
suction blister
thermal lesions

Question 6

What diseases target the basal lamina and sublaminar connective tissue layer

Answer 6

Bullous dermatosis of hemodialysis
bullous eruption of SLE
Epidermolysis bullosa dystrophica
Erythema multiforme (dermal type)
Ischemic bullae (drug overdose)
Lichen sclerosus et atrophicus
porphyria cutanea tarda

Question 7

What diseases target the subcorneal layer

Answer 7

Candida
impetigo
miliaria crystallina 
SSSS
subcorneal pustular dermatosis

Question 8

What diseases target the lower spinous layer

Answer 8

Benign familial chronic pemphigus
keratosis follicularis
pemphigus vulgaris
transient acantholytic dermatosis

Question 9

Target molecule in Pemphigus vulgaris

Answer 9

Desmoglein 3 and 1

Question 10

Target molecule in Pemphigus foliaceous

Answer 10

Desmoglein 1

Question 11

Target molecule in Paraneoplastic pemphigus

Answer 11

Desmoglein 3, desmoplakin 1 and 2, BP230, envoplakin, periplakin, and others

Question 12

Target molecule in IgA Pemphigus

Answer 12

Desmocollin 1

Question 13

Target molecule in BP

Answer 13

BP180, 230 (hemidesmosome and lamina lucida)

Question 14

Target molecule in Herpes gestationis

Answer 14

BP180, 230 (hemidesmosome and lamina lucida)

Question 15

Target molecule in Cicatricial pemphigoid

Answer 15

BP180, laminin V (hemidesmosome and lamina lucida)

Question 16

Target molecule in Epidermolysis bullosa acquisita

Answer 16

Type VII collagen (anchoring fibrils)

Question 17

Target molecule in Linear IgA

Answer 17

LAD antigen (BP180) (hemidesmosome and lamina lucida)

Question 18

Target molecule in Bullous SLE

Answer 18

Type VII collagen (anchoring fibrils)

Question 19

Target molecule in dermatitis herpetiformis

Answer 19

unknown

Question 20

Biopsy work up for blisitering disorders

Answer 20

Take one from the edge of a fresh lesion and one from normal, non-edematous skin

Question 21

What disease process would you want to take a biopsy of the actual lesion (not edge) to perform DIF on?

Answer 21

HSP and vasculitis lesions

Question 22

Dermatitis herpetiformis clinical presentation

Answer 22

usually in 2nd-5th decade
usually in caucasian patients
intensely burning urticarial papules, vesicles symmetrically distributed across extensor surfaces, scalp, and buttocks

Question 23

DDx of DH

Answer 23

bullous erythema multiforme and bullous pemphigoid

Question 24

Associated diseases in DH

Answer 24

Celiac disease

thyroid dysfunction

Question 25

Linear IgA bullous dermatosis clinical presentation

Answer 25

May look like DH, BP, or cicatricial pemhigoid

Question 26

Etiology of Linear IgA bullous dermatosis

Answer 26

Medications such as vancomycin (within 1-15 days after first dose)

Question 27

Histology of DH

Answer 27

IgA deposits in upper dermis | - also see antibodies against epidermal transglutaminase 1 on Indirect immunoflorescence/ELISA

Question 28

Histology for Linear IgA

Answer 28

IgA linear across basement membrane zone

Question 29

How many DH patients have the gluten sensitive enteropathy

Answer 29

majority (there is a direct correlation between IgA anti-endomysial antibodies and the severity of gluten induced jejunal damage)

Question 30

Does dapsone fix the enteropathy

Answer 30

No, just the dermatitis herpetiformis. People still need to be on gluten free diet to avoid MALT lymphoma formation

Question 31

Diagnosis of DH

Answer 31

- Subepidermal cleft with neutrophils and few eos at tips of dermal papillae - IgA on DIF in granular deposits on tips of dermal papillae and along BMZ (not altered if pt on dapsone but gone if gluten free) - anti-endomysial IgA or anti-transglutaminase IgA testing on serum - also screen with CBC, TSH, and blood glucose

Question 32

Diagnosis of linear IgA

Answer 32

just have the IgA at BMZ not dermal papillae tips

Question 33

Treatment of DH

Answer 33

Dapsone and sulfapyradine/sulfasalazine (2nd line) | - reported treatment with tetracycline and nicotinamide combined

Question 34

Monitoring while on Dapsone

Answer 34

- first check G6PD level | - then weekly CBC x 1 mo, monthly x 6mo, then two times per year

Question 35

Adverse reactions to Dapsone

Answer 35

Agranulocytosis, aplastic anemia, peripheral motor neuropathy (resolves over months to years once discontinued)

Question 36

Dapsone hypersensitivity syndrome

Answer 36

- occurs 1 mo or more after starting, Mono like illness + exanthematous rash +/- hepatitis and hypothyroidism - treat with atleast 1 mo of prednisone while monitoring organ dysfunction via labs