In The Name Of GOD

Bullous systemic lupus erythematosus

Vesicles & bullae in patients with SLE Classic lesions of discoid , systemic, or subcutaneous lupus erythematosus (rarely) Previous history of SLE Befor making the diagnosis in patients with bullous lesions

Lesions characteristics: Not symmetrical Not pruritic Not predilection for extensor surfaces of arms,elbows, or scalp Photodistributed or widespread Dramatic response to dapsone therapy

Tense vesiculobullous lesions on the neck

Bullous eruption of systemic lupus erythematosus

Histopathology 3 histologic patterns: 1- Basal layer vacuolization + subsequent blister formation 2-Vasculitis + subepidermal blister & pustule formation 3-Dermatitis herpetiformis-like histologic pattern (most common)

Vasculitis - Small vessel ,neutrophil –rich leukocytoclasstic vasculitis - Beneath the blister - 25% of cases

Histopathology Supepidermal bulla with interface changes in intact areas Neutrophils along DEJ Perivascular and periadnexal infiltrate with increased mucin

Bullous Systemic Lupus Erythematosus: Subepidermal blister ,neutrophils are predominant in the blister & superficial dermis

Systemic lupus erythematosus (Bullous)

IF Testing IgG & C3 deposition Epidermal basement membrane zone (in all cases)

IF Testing Linear pattern > 50% of cases Granular bandlike : 25% of cases IgM deposition : 50% of cases IgA deposition : 60% of cases

Granular patterns In general,deposition of circulating immune complexes in situ or in situ binding of Ag and Ab

Direct immunofluorescent studies will show homogeneous linear staining along the dermal-epidermal junction. Salt split skin studies show localization to the floor

C3 linear basement membrane zone (40x)

IIF study IIF study of serum Circulating anti-squamous basement membrane zone antibodies (rarely) against type VII collagen

IIF study Salt-split skin preparation more sensitive substrate localization to the split floor (as EBA)

Ultrastructural Study Immunelectron microscopic examination: Electron-dense deposits of IgG lower edge of basal lamina & immediately adjacent dermis

Differential Diagnoses Bullous Pemphigoid Dermatitis Herpetiformis Epidermolysis Bullosa Acquisita (EBA) Drug-Induced Bullous Disorders Linear IgA Dermatosis Dermatologic Manifestations of Graft Versus Host Disease Epidermolysis Bullosa Erythema Multiforme Hydroa Vacciniforme Porphyria Cutanea Tarda Pseudoporphyria

Differential Diagnoses Dermatitis Herpetiformis - Subepidermal blister containing predominantly neutrophils with rare eosinophils Neutrophilic microabscesses in dermal papillae DIF : Granular IgA deposition in dermal papillae, with/without linear deposits of IgA at BMZ.

Differential Diagnoses Bullous Pemphigoid Subepidermal bulla containing eosinophils with admixed lymphocytes and neutrophils Superficial perivascular and interstitial lymphocytic infiltrate with eosinophils DIF : IgG and C3 at DEJ.

Differential Diagnoses Linear IgA Bullous Dermatosis -Supepidermal blister formation with papillary dermal edema -Linearly aligned neutrophils along DEJ -Superficial perivascular and interstitial neutrophilic infiltrate with admixed eosinophils and lymphocytes may be seen -DIF : Linear IgA at DEJ

Differential Diagnoses Bullous Drug Eruption Subepidermal blister with associated perivascular and interstitial mixed infiltrate Admixed eosinophils DIF : Negative

Differential Diagnoses Epidermolysis Bullosa Acquisita Supepidermal blister with minimal inflammation, or mimicking pemphigoid DIF : Linear IgG and C3 at DEJ Distinguishing from EBA with neutrophil-rich inflammatory cell infiltrate may be achieved by lupus serologies, and relatively quick response to dapsone or azathioprine in bullous SLE (EBA is usually resistant to therapy)