[1] Newcastle Univ, Fac Med Sci, Dept Rheumatol, Newcastle Upon Tyne NE2 4HH, Tyne & Wear, England
[2] St James Univ Hosp, Mol Med Unit, Leeds, W Yorkshire, England
[3] Univ Manchester, Acad Unit Child Hlth, Booth Hall Childrens Hosp, Manchester, Lancs, England