Subcorneal pustular dermatosis--an unusual course

Area of Science:

• Dermatology
• Immunology
• Allergy

Background:

• Subcorneal pustular dermatosis (SPD) is a rare inflammatory skin condition.
• Understanding triggers for SPD exacerbations is crucial for patient management.

Observation:

• A patient with SPD experienced new pustular lesions after drug eruptions from dapsone and quinidine sulphate.
• The patient also showed lesion flares after intradermal injections of Candida and streptokinase-streptodornase recall antigens.

Findings:

• Both drug eruptions were likely immediate-type hypersensitivity reactions, supported by positive mast cell degranulation tests.
• Recall antigen testing indicated a role for delayed hypersensitivity in triggering SPD flares.

Implications:

• This case highlights potential triggers for subcorneal pustular dermatosis flares.
• Immediate and delayed hypersensitivity mechanisms may contribute to the pathogenesis of SPD.