1. Department of Dermatology,
St George’s Hospital,
London SW17 0QT, U.K.
*Department of Dermatology,
St Helier Hospital,
Carshalton SM5 1AA, U.K.
†St John’s Institue of Dermatology,
St Thomas’ Hospital,
London SE1 7EH, U.K.
E‐mail:
Correspondence: Dr S.L.Walker, Department of Dermatology,
Royal Lancaster Infirmary, Lancaster LA1 4RP, U.K.