[1] Manchester Royal Infirm, Dept Genitourinary Med, Manchester M13 9WL, Lancs, England
[2] Withington Hosp, Manchester M20 8LR, Lancs, England
[3] N Manchester Grp Hosp, Pennine Acute Hosp NHS Trust, Dept Genitourinary Med, Manchester M8 5RB, Lancs, England