[1] Leicester Royal Infirm, Dept Dermatol, Leicester LE1 5WW, Leics, England
[2] Univ Dundee, Ninewells Hosp & Med Sch, Dept Clin Pharmacol, Div Med & Therapeut, Dundee DD1 9SY, Scotland
[3] Univ Leicester, Dept Infect Immun & Inflammat, Leicester, Leics, England
[4] Altnagelvin Hosp, Dept Rheumatol, Londonderry, North Ireland