title: Renal damage detected by DMSA, despite normal renal ultrasound, in children with febrile UTI.
abstract: OBJECTIVE
  2011 American Academy of Pediatrics guidelines recommended renal-bladder ultrasound (RBUS) as the only evaluation after febrile urinary tract infection (FUTI) in infants aged 2-24 months. We determined the sensitivity, specificity, and false negative rate of RBUS to identify DMSA-detected renal damage in this age group as well as in older children.
  
  
  METHODS
  Consecutive patients referred to pediatric urology with a history of FUTI underwent DMSA ≥ 3 months after FUTI. Abnormal RBUS was defined as: Society of Fetal Urology hydronephrosis grades I-IV; hydroureter ≥ 7 mm; renal scar defined as focal parenchymal thinning; and/or size discrepancy ≥ 1 cm between kidneys. Abnormal DMSA was presence of any focal uptake defects and/or split renal function < 44%. We calculated sensitivity, specificity, positive and negative predictive values, and false negative rates of RBUS compared to DMSA.
  
  
  RESULTS
  618 patients (79% female), median age 3.4 years, were referred for FUTIs. Of the 512 (83%) with normal RBUS, 99 (19%) had abnormal DMSA. Children with normal RBUS after their first FUTI had abnormal DMSA in 15/151 (10%) aged ≤ 24 months and 23/119 (19%) aged > 24 months. RBUS had poor sensitivity (34%) and low positive predictive value (47%) to identify patients with renal damage. 99/149 (66%) children with renal damage on DMSA had normal RBUS.
  
  
  CONCLUSIONS
  After FUTI, 66% of children with reduced renal function and/or renal cortical defects found by DMSA scintigraphy had a normal RBUS. Since abnormal DMSA may correlate with increased risk for VUR, recurrent FUTI and renal damage, our data suggest RBUS alone will fail to detect a significant proportion of patients at risk. The data suggest that imaging after FUTI should include acute RBUS and delayed DMSA, reserving VCUG for patients with abnormal DMSA and/or recurrent FUTI.
authors.affiliation: Pediatric & Adult Reconstructive Center for Urology, Dallas, TX, USA. Electronic address: bush@parcurology.com.
authors.forename: N C
authors.initials: NC
authors.lastname: Bush
authors.affiliation: Children's Hospital of Eastern Ontario, Ottawa, Canada. Electronic address: mkeays@cheo.on.ca.
authors.forename: M
authors.initials: M
authors.lastname: Keays
authors.affiliation: University of Texas Southwestern, Dallas, TX, USA.
authors.forename: C
authors.initials: C
authors.lastname: Adams
authors.affiliation: Pediatric & Adult Reconstructive Center for Urology, Dallas, TX, USA. Electronic address: mizener@parcurology.com.
authors.forename: K
authors.initials: K
authors.lastname: Mizener
authors.affiliation: University of Texas Southwestern, Dallas, TX, USA.
authors.forename: K
authors.initials: K
authors.lastname: Pritzker
authors.affiliation: University of Texas Southwestern, Dallas, TX, USA.
authors.forename: W
authors.initials: W
authors.lastname: Smith
authors.affiliation: University of Texas Southwestern, Dallas, TX, USA.
authors.forename: J
authors.initials: J
authors.lastname: Traylor
authors.affiliation: Children's Hospital and Medical Center, University of Nebraska, Omaha, NE, USA.
authors.forename: C
authors.initials: C
authors.lastname: Villanueva
authors.affiliation: Pediatric & Adult Reconstructive Center for Urology, Dallas, TX, USA. Electronic address: snodgrass@parcurology.com.
authors.forename: W T
authors.initials: WT
authors.lastname: Snodgrass
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005188:False Negative Reactions; D005260:Female; D005334:Fever / Q000150:complications* / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007674:Kidney Diseases / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D014463:Ultrasonography; D014552:Urinary Tract Infections / Q000150:complications* / Q000000981:diagnostic imaging*; D014718:Vesico-Ureteral Reflux / Q000150:complications / Q000000981:diagnostic imaging
chemical_list: D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
keywords: DMSA; Renal ultrasonography; UTI; VUR