The pemphigoid group of diseases

Question 1

BP epidemiology

Answer 1

• usually occurs after age 80
• associated with neurologic disease such as CVA or MS which predate the pemphigoid
• can be precipitated by medications

Question 2

BP clinical manifestations

Answer 2

Progression: localized erythema that becomes pruritic urticarial plaques-> EM like red/cyanotic plaques in 1-3 weeks-> tense vesicles and bullae on the surface
- MC sites are lower abdomen, groin, flexor arms and legs

Question 3

Localized clinical variants of BP

Answer 3

Vesicular, vegetating, hyperkeratotic, erythrodermic

Question 4

DDx of BP

Answer 4

Epidermolysis bullosa acquisita
DH
Pemphigus
bullous SLE
bullous drug eruption 
Others: bug bits, cellulitis, EM, contact derm

Question 5

Course and prognosis of BP

Answer 5

If generalized, poor prognosis especially if BP180 autoantibody +
If localized-> may become generalized or regress
- no clinical/immunologic/immunogenic factors predict disease duration

Question 6

Lab diagnosis of BP

Answer 6

• often see elevated IgE and eosinophilia

Question 7

W/U of BP

Answer 7

Two biopsies (1. perilesional for DIF and 2. intact elsion for histopathology)
Serum for BP180, 230 as well as desmoglein 1 and 3 autoantibodies (BP180 titers decrease with disease activity)

Question 8

DIF findings in BP

Answer 8

• linear deposits of IgG +/ C3 along BMZ

- salt split skin would show auto-antibodies on the roof (unlike epidermolysis bullosa acquisita)

Question 9

Treatment of BP (mild/localized)

Answer 9

Topical steroids to affected areas, low dose systemic steroids (0.3mg/kg/day), antiinflammatory antibiotics

Question 10

Treatment of BP (moderate to severe)

Answer 10

systemic steroids (0.5-1mg/kg/day) with Calcium, VitD, and PPI protection
very potent topical steroids to whole skin surface
anti-inflammatory antibiotics

Question 11

Treatment of BP (refractory)

Answer 11

• can add nicotinamide to anti-inflammatory antibiotics
• Imuran (be sure to look at TPMT activity)
• methotrexate (with folic acid)
• dapsone
• chlorambucil
• rituximab

Question 12

Treatment of BP (exceptional cases)

Answer 12

• CellCept 0.5-1gm BID
• IVIG
• cyclophosphamide
• plasmaphoresis

Question 13

Localized pemphigoid examples

Answer 13

• Cicatricial (Mucous membrane)
• localized childhood vulvar pemphigoid (use group III-V steroids)
• pretibial pemphigoid (non-scaring usually in women)
• chronic pemphigoid of Brunsting-Perry (crops of grouped blisters on the head and neck that heal with atrophic scars)
• dyshidrosiform pemphigoid (vesiculobullous hemorrhagic lesions of palms and soles)
• Pemphigoid vegetans (erosive and vegetating plaques)

Question 14

MM Pemphigoid epidemiology

Answer 14

• patients older than 40 with female predominance

Question 15

MM Pemphigoid etiology

Answer 15

autoantibodies to BMZ antigens (lamina lucida proteins involved in keratinocyte adhesion to extracellular matrix)

Question 16

Oral MM pemphigoid

Answer 16

MC site is desquamative gingitivits

• vermillion border spared unlike pemphigus
• relatively painless erosions

Question 17

Ocular MM pemphigoid

Answer 17

MC presentation is unilateral conjunctivitis which progresses to bilateral

• gradual scaring of conjunctiva leads to obliteration of conjunctival sac
• leads to blindness in ~20% of patients

Question 18

Treatment of MM Pemphigoid

Answer 18

treat as like BP (be aggressive in ocular/laryngeal/genital involvement)

Question 19

Topical treatment of MMP

Answer 19

• oral (hydrogen peroxide + dexamethasone + diphenydramine all swish and spit OR fluocinonide gel)
• eye (artificial tears + systemic steroids as topicals less effective)

Question 20

Systemic treatment of MMP

Answer 20

Dapsone
Steroids
steroid sparing agents such as Imuran, Cyclophosphamide, methotrexate, cyclosporine, or CellCept

Question 21

Benign chronic bullous dermatosis of childhood clinical presentation

Answer 21

Large tense blisters on face (around mouth), lower trunk, inner thighs, and genitalia

• resolves by puberty at the latest
• normal jejunal biopsy

Question 22

Benign chronic bullous dermatosis of childhood DIF

Answer 22

linear IgA deposits at BMZ

Question 23

Benign chronic bullous dermatosis of childhood treatment

Answer 23

Dapsone as in DH followed by steroids if needed

Question 24

Herpes gestationis etiology

Answer 24

Genetic predisposition

- mediated by IgG1 specific for the 180kDa component of hemidesmosomes

Question 25

Herpes gestationis clinical presentation

Answer 25

• tends to recurr in subsequent pregnancies and be more severe
• associated with premature birth
• usually starts in 2nd or 3rd trimester
• resolves 1-2 months post-partum
• edematous plaques occur in crops on abdomen and extremities then coalesce into polycyclic rings covering much of the skin
• heal with PIH
• affects baby’s skin in 10% of cases

Question 26

Herpes gestationis dx

Answer 26

Band-like deposit of C3 at BMZ (like in BP)

- IIF shows IgG BMZ antibodies that are capable of fixing complement (** HG IgG which is unique feature)

Question 27

Herpes gestationis tx

Answer 27

topical steroids if mild

oral steroids typically (watch for reversible adrenal insufficiency in newborns)