A 4-year-old girl presents with annular clusters of tense blisters arranged like a 'string of pearls' around the periphery of erythematous plaques on the lower abdomen and groin. Direct immunofluorescence shows linear IgA along the basement membrane zone. The most likely diagnosis is:
- A Childhood bullous pemphigoid
- B Chronic bullous disease of childhood ✓
- C Dermatitis herpetiformis
- D Epidermolysis bullosa simplex
Correct answer: B. Chronic bullous disease of childhood
Explanation
Chronic bullous disease of childhood, the paediatric form of linear IgA bullous dermatosis, classically produces the 'string of pearls' sign: new vesicles arranged at the rim of healing annular lesions. Dermatitis herpetiformis shows granular, not linear, IgA in papillary tips and favours extensor surfaces. Epidermolysis bullosa simplex is genetic with no immunofluorescence deposits.
Reference: Rook's Textbook of Dermatology, 9th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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