title: The role of indirect radionuclide cystography during the acute phase of pyelonephritis in young women.
abstract: OBJECTIVE
  To review our experience using dynamic 99mTc-diethylenetriamine penta-acetic acid renal scintigraphy combined with indirect radionuclide cystography (IRC) in the acute phase of pyelonephritis, as a possible alternative to the conventional imaging, as investigating acute pyelonephritis usually includes imaging the upper urinary tract during the acute phase, to exclude obstruction, and delayed voiding cysto-urethrography (VCUG) when underlying vesico-ureteric reflux (VUR) is suspected.
  
  
  METHODS
  Between 1997 and 1999, 47 young women (median age 22 years, range 18-37) were hospitalized for acute pyelonephritis. The combined study was used during the acute phase of the disease, usually within 24 h of hospitalization. The principle of IRC is based on the reappearance of radioactivity in the ureters or kidneys after previously detecting renal clearance of an intravenously injected radioisotope. The increase in radioactivity over the ureters or kidneys indicates VUR. The subsequent follow-up included VCUG, after recovery and at least 6 weeks after discharge.
  
  
  RESULTS
  Overall, 47 patients had early IRC studies; obstruction of the urinary tract during the acute phase of the disease was excluded in all. In 13 (28%) of the patients early IRC studies showed VUR involving 21 upper tract units. The renal parenchymal scan was impaired in 17 (36%) patients, and six of these 17 also had detectable concomitant reflux on IRC. Overall, 24 IRC studies (51%) were considered positive, showing VUR, renal parenchymal pathology or both; 23 (49%) were normal. Follow-up VCUG was used in 32 patients (68%); only three (9%) detected VUR. All of the patients with VUR on follow-up VCUG had also had an abnormal early IRC study, showing either reflux (two) or findings suggestive of pathological renal parenchyma (one).
  
  
  CONCLUSIONS
  In addition to the well-established role of renal scintigraphy in excluding obstruction of the collecting system, early IRC is characterized by high sensitivity and accurate negative predictive value for detecting VUR. It can therefore be used to screen adults presenting with acute pyelonephritis for the presence of VUR. Patients with an abnormal IRC require follow-up VCUG after complete recovery, while those with a negative study may be managed expectantly, with no further radiological evaluation. This proposed strategy may avoid up to half of the delayed VCUG studies, preclude the related inconvenience, and substantially reduce the costs.
authors.affiliation: Department of Urology, The Chaim Sheba Medical Center, Tel Hashomer, Affiliated to Sackler School of Medicine, Tel Aviv University, Israel.
authors.forename: Jehonathan H
authors.initials: JH
authors.lastname: Pinthus
authors.forename: Yakov
authors.initials: Y
authors.lastname: Oksman
authors.forename: Ilan
authors.initials: I
authors.lastname: Leibovitch
authors.forename: Elinor
authors.initials: E
authors.lastname: Goshen
authors.forename: Zohar A
authors.initials: ZA
authors.lastname: Dotan
authors.forename: Arnon
authors.initials: A
authors.lastname: Schwartz
authors.forename: Jacob
authors.initials: J
authors.lastname: Ramon
authors.forename: S Tzila
authors.initials: ST
authors.lastname: Zwas
authors.forename: Yoram
authors.initials: Y
authors.lastname: Mor
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D011704:Pyelonephritis / Q000000981:diagnostic imaging*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D001743:Urinary Bladder / Q000000981:diagnostic imaging*; D014718:Vesico-Ureteral Reflux / Q000000981:diagnostic imaging
chemical_list: D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid