Does cutaneous lupus typically present with a central blister?

Cutaneous Lupus Erythematosus Does Not Typically Present with a Central Blister

Cutaneous lupus erythematosus does not characteristically present with central blisters; however, a specific subtype called bullous lupus erythematosus does feature blistering as its primary manifestation.

Clinical Presentation of Cutaneous Lupus Erythematosus

• Cutaneous lupus erythematosus (CLE) typically presents with erythematous, scaly plaques that may have well-demarcated borders, particularly in chronic forms like discoid lupus 1
• The classic presentation includes red to brown macules, papules, plaques or nodules, often in sun-exposed areas, without central blistering 1
• Three main recognized subtypes of cutaneous lupus are acute cutaneous LE (ACLE), subacute cutaneous LE (SCLE), and chronic cutaneous LE (CCLE), with each having distinct clinical presentations that generally do not include central blisters 2

Bullous Lupus Erythematosus - The Exception

• Bullous systemic lupus erythematosus (BSLE) is a rare blistering presentation of lupus that features vesiculobullous eruptions 3
• In BSLE, bullae can arise from erythematous macules, inflammatory plaques, or previously normal skin, but this is considered a distinct subtype rather than a typical feature of cutaneous lupus 3
• The blisters in BSLE typically appear as tense bullae that can resemble bullous pemphigoid, rather than having a characteristic "central" blister pattern 3

Differential Diagnosis of Blistering Skin Conditions

• Bullous pemphigoid presents with tense blisters arising on erythematous or normal-looking skin, typically on the limbs and trunk, and is more common in elderly patients 4
• In bullous pemphigoid, the blisters are subepidermal and contain eosinophils and/or neutrophils, which differs from the histopathology typically seen in cutaneous lupus 4
• The presence of satellite lesions with blistering is more characteristic of fungal infections like tinea cruris rather than lupus 5

Histopathological Features

• Non-bullous neutrophilic lupus erythematosus is a rare form of CLE that shows interface vacuolar change and neutrophils in the dermis without bulla formation, which may represent a muted form of bullous lupus in patients on immunosuppression 6
• Standard cutaneous lupus typically shows interface dermatitis with basal cell vacuolization and dermal lymphocytic infiltrate, without primary blister formation 1
• When blisters do occur in lupus, they are due to autoantibodies against type VII collagen, which weaken the basement membrane zone and lead to subepidermal blister formation 3

Clinical Pearls and Pitfalls

• The presence of blisters in a patient with known lupus should prompt consideration of bullous systemic lupus erythematosus as a specific subtype or a separate concurrent blistering disorder 3
• Histopathologic examination is crucial in evaluating any new skin lesions in patients with lupus, especially those on therapy, as treatment may modify the typical presentation 6
• Uncommon cutaneous manifestations of lupus can occur, making diagnosis challenging when classic features are absent 7

Management Considerations

• First-line management of bullous lupus typically includes dapsone for mild disease with stable underlying systemic lupus erythematosus 3
• For standard cutaneous lupus without blistering, treatments include photoprotective strategies, topical therapies (corticosteroids and calcineurin inhibitors), and systemic agents like hydroxychloroquine 1
• Rituximab has been shown to be effective in refractory cases of bullous lupus unresponsive to conventional therapies 3