The diagnostic yield of intravenous urography

Background. Intravenous urography (IVU) is considered an integral imaging c omponent of the nephrourological work-up in a wide array of clinical settin gs. At our institution there is an open-access policy with regard to reques ting IVU studies. Methods. In a prospective, blinded observational study we undertook to asse ss the diagnostic yield of IVU with respect to the source of referral (i.e. Urology, Nephrology, GP, A & E, other speciality) and the presenting featu res, such as renal colic, haematuria, bladder outflow obstruction, recurren t urinary tract infection (UTI) etc. Two hundred consecutive patients were evaluated. Results. Overall, 23% of tests were positive. There was a highly significan t difference in diagnostic yield between the groups (P<0.001 for both refer ral source and test indication). A positive result was most likely after re ferral by a kidney specialist (37.1%) and when the test indication was rena l colic (42%) or haematuria (32%). The yield was <15% in all other circumst ances, with 94.9% and 92.1% of GP- and other hospital speciality-initiated IVUs being negative. When investigating recurrent UTI, 91.7% of tests were negative and 86.2% were negative when the indication was bladder outflow ob struction. Conclusions. It is suggested that an open access policy for IVU is not just ified, especially when cost and the risk associated with contrast media and radiation exposure are taken into account. Our study supports the abandonm ent of routine IVU in the investigation of UTI and bladder outflow obstruct ion.