DisorderEpidemiologyClinical featuresDiagnosisTreatmentComments
Pemphigus vulgarisRare, equal in men and women, onset at 40 to 60 years of age, more common in Jewish or Mediterranean descendantsFlaccid blisters or crushed erosions, located on head, upper trunk, intertriginous areas, and mucosa; often begins on oral mucosa, may lead to hoarseness; skin is usually painful and Nikolsky's sign positiveLight: suprabasilar blister with acantholysis
DIF: intercellular IgG and C3
Corticosteroids (prednisone, 1 mg per kg per day) taper to maintenance; may add azathioprine (Imuran), methotrexate, cyclophosphamide (Cytoxan), mycophenolate mofetil (CellCept); plasmapheresisMay be fatal if untreated, risk of infection in treated and untreated cases
Paraneoplastic pemphigusVery rare, female to male ratio is 2:1, onset at 60 years and older, associated with malignancy, most often lymphoidExtensive painful mucocutaneous erosions, resembling pemphigus vulgaris, in the presence of neoplasm; targetoid erythematous papules with dusky centers resembling erythema multiforme may also be presentLight: suprabasilar blister with acantholysis (PV-like), with basal cell vacuolation, exocytosis, and dyskeratotic keratinocytes (erythema multiforme-like)Detection and treatment of the neoplasmUsually rapidly fatal if associated with a malignant neoplasm
DIF: intercellular and basement membrane IgG and C3
IIF: positive for rat bladder (cuboidal epithelium) and stratified squamous epithelium
Bullous pemphigoidEqual in men and women, onset at 60 to 80 years of age, rarely in childrenTense bullae with clear fluid or erosions, may begin as erythematous urticarial, pruritic plaques, localized or generalized on the lower legs, forearms, thighs, groin, abdomen, but rarely on mucosaLight: subepidermal blister with mixed superficial inflammation
DIF: IgG and/or C3 at the basement membrane
Corticosteroids (prednisone) alone or with azathioprine, mycophenolate mofetil or a tetracyclineSelf-limited, rarely fatal even if untreated
Cicatricial pemphigoidRare, female to male ratio is 2:1, onset at 40 to 60 years of ageBullae rupture within hours leaving painful erosions that heal with scarring; most common sites are oral and conjunctival mucosa; skin involved in one third of cases, head and upper chestLight: subepidermal blister with mixed infiltrate in fresh lesions and predominant fibroblasts in older, scarring lesionsCorticosteroids; may add dapsone for oral involvement or cyclophosphamide or azathioprine for ocular involvement; topical treatment of oral lesions with steroid gel or dexamethasone mouthwash (Roxane)Ocular lesions may lead to blindness; oral complications include laryngeal or esophageal strictures with dysphagia, hoarseness, loss of voice, or need for tracheostomy
DIF: linear IgG and C3 on the basement membrane, +/− IgA or IgM treatment of oral lesions
Dermatitis herpetiformis (dapsone)Rare, male to female ratio is 2:1, onset at 20 to 40 years of age, but also in children, whites, rare in blacks or AsiansGrouped (herpetiform) excoriations or vesicles symmetrically located on extensor remission; watch for signs surfaces of elbows, knees, sacrum, buttocks, and shoulders with intense pruritus and burning sensationLight: neutrophilic abscesses in dermal papillae, dermal infiltrates of neutrophils and eosinophils with subepidermal vesiclesGluten-free diet; sulfones dermal infiltrates of neutrophils and eosinophilsChronic with occasional remission; watch for signs of other autoimmune disorders; may coexist with gluten-sensitive enteropathy
DIF: granular IgA deposits in the tips of the dermal papillae
Linear IgA dermatosis (LAD) or chronic bullous disease of childhood (CBDC)LAD: equal in men and women, onset after puberty, usually in 30sLAD: pruritic symmetric grouped annular crusted papules, vesicles, or bullae on extensor surfaces, elbows, knees, or buttocksLight : subepidermal bullae with infiltrate of neutrophils at basement membrane and dermal papillae tipsSulfones (dapsone) +/− low-dose prednisoneLAD: variable course
CBDC: onset before age fiveCBDC: rings of grouped bullae around old lesions on genitalia, face, or perioral areaDIF: linear deposits of IgA along the basement membrane, +/− IgG and C3CBDC: usually clears in two years or less