Author: Dr Ian Coulson, Consultant Dermatologist and Editor-in-Chief (2025).
Edited by the DermNet content department.
This five-year-old boy has a four-month history of recurring blisters on his leg and genitalia.
There are tense blisters arising on the affected skin, developing in rings. They are sometimes described as a ‘cluster of jewels’.
The age of the child and the morphology of the blisters, coupled with location on the genitalia, suggest chronic bullous disease of childhood (also known as linear IgA disease).
The investigation of choice is direct immunofluorescence performed on skin adjacent to a blister. This shows a linear band of IgA at the dermo-epidermal junction. This contrasts with the granular IgA deposits seen in dermatitis herpetiformis.
Treatment involves the use of a potent topical steroid cream and oral dapsone.
