[1] Imperial Coll Hosp NHS Trust, St Marys Hosp, Dept Dermatol, London W2 1NY, England
[2] Imperial Coll Hosp NHS Trust, St Marys Hosp, Dept Rheumatol, London W2 1NY, England
[3] Univ London Imperial Coll Sci Technol & Med, Ctr Pathol, London, England