title: Recurrent urinary tract infections in young children: role of DMSA scintigraphy in detecting vesicoureteric reflux.
abstract: BACKGROUND
  Performing micturiting cystourethrography (MCUG) in young children with recurrent urinary tract infections is controversial with discrepancy among the major guidelines.
  
  
  OBJECTIVE
  Previous studies have shown that a normal dimercaptosuccinic acid (DMSA) scintigraphy may avoid the need of performing MCUG for detecting vesicoureteric reflux in children with first febrile urinary tract infection. However, the role of DMSA for ruling out vesicoureteric reflux in children with recurrent urinary tract infections has not been studied.
  
  
  METHODS
  Approval from institutional ethical review committee was sought and the requirement of informed consent was waived. A total of 50 children under the age of 10 years with recurrent urinary tract infections underwent MCUG scan within 3 months of DMSA scan from January 2011 to September 2012 at our institution. Diagnosis of recurrent urinary tract infections and grading of vesicoureteric reflux was according to previously established standards. Abnormalities on DMSA scan - scarring, hydronephrosis and reduced differential renal function - were compared with presence of vesicoureteric reflux on MCUG.
  
  
  RESULTS
  High-grade vesicoureteric reflux was noted on MCUG in 22 (44%) cases. The findings on DMSA included hydronephrosis and scarring in 25 (50%) and 25 (50%) cases, respectively. Abnormalities on DMSA scan for detecting the presence of high-grade vesicoureteric reflux on MCUG examination had sensitivity, specificity, positive and negative predictive values of 95.45%, 35.71%, 53.85% and 90.91%, respectively. The positive and negative likelihood ratios were 1.48 and 0.13 respectively.
  
  
  CONCLUSIONS
  DMSA scan had high overall sensitivity and negative predictive value with a low negative likelihood ratio for ruling out high-grade vesicoureteric reflux on MCUG, which may obviate the need of invasive MCUG along with its associated drawbacks.
authors.affiliation: Department of Radiology, Aga Khan University Hospital, Stadium Road, Karachi, 74800, Pakistan, jsmawais@yahoo.com.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Awais
authors.forename: Abdul
authors.initials: A
authors.lastname: Rehman
authors.forename: Maseeh Uz
authors.initials: MU
authors.lastname: Zaman
authors.forename: Naila
authors.initials: N
authors.lastname: Nadeem
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011877:Radionuclide Imaging / Q000379:methods; D019275:Radiopharmaceuticals; D012008:Recurrence; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D014552:Urinary Tract Infections / Q000150:complications* / Q000175:diagnosis*; D014554:Urination; D014567:Urography / Q000379:methods*; D014718:Vesico-Ureteral Reflux / Q000175:diagnosis* / Q000209:etiology*
chemical_list: D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid