9 - 52 - PEMPHIGUS

Question 1

give examples of Intraepidermal Blistering Diseases Without Autoantibodies

Answer 1

■ Familial benign pemphigus (Hailey-Hailey disease)

■ Bullous impetigo, staphylococcal scalded-skin syndrome

■ Blisters from herpes simplex and zoster

■ Allergic contact dermatitis (eg, rhus dermatitis)

■ Epidermolysis bullosa simplex

■ Incontinentia pigmenti

Question 2

give examples of Mouth Ulcers/Erosion Without Autoantibodies

Answer 2

■ Aphthous ulcers

■ Candidiasis

■ Lichen planus

■ Behçet disease

Question 2

give examples of Subepidermal Blistering Diseases With Autoantibodies

Answer 2

■ Bullous pemphigoid

■ Herpes gestationis

■ Cicatricial pemphigoid

■ Epidermolysis bullosa acquisita

■ Linear IgA disease and chronic bullous disease of childhood

■ Dermatitis herpetiformis

■ Bullous lupus erythematosus

Question 3

give examples of Subepidermal Blistering Diseases Without Autoantibodies

Answer 3

■ Erythema multiforme

■ Toxic epidermal necrolysis

■ Porphyria

■ Junctional or dystrophic epidermolysis bullosa

Question 3

Question 4

distribution of lesions in PV

Answer 4

The primary lesion of PV is a flaccid blister, which may occur anywhere on the skin surface, but typically not the palms and soles

Question 5

primary lesion of PV

Answer 5

flaccid blister

Question 5

erosions can be extended into visibly normal skin by pulling the remnant of the blister wall or rubbing at the periphery of active lesions; additionally, erosions can be induced in normal-appearing skin distant from active lesions by pressure or mechanical shear force.

This phenomenon is known as?

Answer 5

Nikolsky sign

Question 6

pemphigus vegetans manifestations and areas of predilection

Answer 6

excessive papillimatosis and crusting, referred to as vegetating lesions occurring more frequently in intertriginous areas, in the scalp, or on the face

Question 6

Conditions where nikolsky sign can be elicited?

Answer 6

PV, staphylococcal scalded skin syndrome, Stevens-Johnson syndrome, and toxic epidermal necrolysis

Question 7

mucous membranes most often affected by PV

Answer 7

oropharyngeal cavity and nasal mucosa

Question 8

In the majority of patients, what are the **presenting sign of PV **and may be the only sign for an average of 5 months before skin lesions develop

Answer 8

painful mucous membrane erosions

Question 9

clinical manifestations and areas of predilection of PF

Answer 9

• The characteristic clinical lesions of PF are scaly, crusted erosions, often on an erythematous base.
• In more localized and early disease, these lesions are usually well demarcated and scattered in a seborrheic distribution, including the face, scalp, and upper trunk

Question 10

localized form of PF with better prognosis

Answer 10

Pemphigus erythematosus

Question 11

drug-induced pemphigus is commonly caused by what medications?

Answer 11

penicillamine and captopril

Question 12

associated conditions with PV

Answer 12

Myasthenia gravis, thymoma

Recent epidemiologic studies have identified that pemphigus vulgaris patients have a higher prevalence of autoimmune thyroid disease, rheumatoid arthritis, and Type 1 diabetes compared with the general population

Question 13

PF antigen (as well as the fogo selvagem antigen)

Answer 13

desmoglein 1, a 160-kDa protein

Question 14

PV antigen

Answer 14

desmoglein 3, a 130-kDa protein

Question 15

T/F

All patients with PV have antidesmoglein 3 antibodies, and some of these patients also have anti–desmoglein 1 antibodies

Answer 15

True

Question 16

Patients with mucosal-dominant PV tend to have only antibodies to what?

Answer 16

Patients with mucosal-dominant PV tend to have only antidesmoglein 3 antibodies

Question 17

mucocutaneous PV usually have antibodies to what?

Answer 17

both **anti–desmoglein 3 and anti–desmoglein 1 **antibodies

Question 18

PF patients typically have antibodies against only what antigen?

Answer 18

desmoglein 1

Question 18

this IgG subclass , which does not fix complement, has been shown to be both pathogenic and the predominant IgG subclass in both PF and PV

Answer 18

IgG4

Question 19

hallmark of pemphigus

Answer 19

finding of immunoglobulin G (IgG) autoantibodies against the cell surface of keratinocytes

Question 20

substrate used to detect pemphigus antibody in PV with higher sensitivity

Answer 20

monkey esophagus

Question 21

substrate used to detect pemphigus antibody in PF with higher sensitivity

Answer 21

**guinea pig esophagus or normal human skin** is a superior substrate for detecting PF antibodies.

Question 22

more sensitive and specific than immunofluorescence, and their** titer correlates better** than that of indirect immunofluorescence with **disease activity**

Answer 22

ENZYME-LINKED IMMUNOSORBENT ASSAY

Question 23

specimen for ELISA

Answer 23

patient serum ## Footnote These assays use desmogleins 1 and 3 bound to plates, which are then incubated with patient sera and developed with anti-human IgG reagents

Question 24

histopathology of early blisters in PF

Answer 24

acantholysis (loss of cell-to-cell contact) just below the stratum corneum and in the granular layer

Question 25

characteristic histopathologic finding in PV

Answer 25

suprabasal blister with acantholysis

Question 26

remains the mainstay of therapy for pemphigus

Answer 26

systemic administration of glucocorticoids, usually prednisone

Question 27

full systemic dose of glucocorticoids

Answer 27

1.5 mg/kg/d of prednisone equivalent for 2 to 3 weeks ## Footnote * However, many patients can be brought under control with a 0.5- to 1.0-mg/kg/d single daily dose, especially if used in combination with adjunctive immunosuppressive therapy * For patients who do not initially respond or worsen, splitting the dose using a twice- or 3-timesdaily schedule may achieve disease control.

Question 28

Minimal therapy definition for systemic steroids

Answer 28

5 to 10 mg daily of prednisone equivalent

Question 29

monoclonal anti-CD20 antibody approved by the FDA for therapy of pemphigus vulgaris

Answer 29

rituximab ## Footnote Rituximab targets B cells, the precursors of antibody-producing plasmablasts. The B cell also acts to process autoantigen and present it to T cells that provide “help” in stimulating the autoantibody response.

Question 30

In patients with normal TPMT levels, the consensus dosing regimen that defines treatment failure with azathioprine

Answer 30

2.5 mg/kg/d for 12 weeks