[1] Univ Surrey, Surrey Pathol Partnership, Immunol, Guildford GU2 5XH, Surrey, England
[2] Univ Surrey, Dept Hlth Care Management & Policy, Guildford GU2 5XH, Surrey, England
[3] Frimley Pk Hosp, Gastroenterol & Hepatol, Frimley, Surrey, England
[4] Royal Surrey Cty Hosp, Immunol, Guildford, Surrey, England
[5] Univ Surrey, Fac Hlth & Med Sci, Guildford GU2 5XH, Surrey, England