title: Outcome of small residual stone fragments following shock wave lithotripsy in children.
abstract: OBJECTIVE
  We evaluate the outcome of small residual stone fragments (RF) following extra-corporeal shock wave lithotripsy (ESWL, Dornier Medical Systems, Inc., Marietta, Georgia) in children.
  
  
  METHODS
  The medical records of 39 boys and 44 girls (88 renal units) with urolithiasis who underwent ESWL were reviewed. Median patient age was 7 years. Average stone burden was 14 mm. Mean followup was 46 months. After the first ESWL 40 of the 88 (46%) renal units became stone-free and 18 (20%) had RF 5 mm or less. The remaining 30 (34%) units required further treatment using ESWL or ancillary surgical procedures that rendered 12 of them stone-free and 8 with RF. The 26 renal units with RF constitute our study subjects. Adverse outcomes such as growth of RF, symptomatic episodes or calculi recurrence in stone-free cases were recorded.
  
  
  RESULTS
  Of the 26 renal units with RF 5 mm or less, 18 (69%) had an adverse clinical outcome (symptoms or RF growth) and 8 (31%) patients were asymptomatic and had no stone growth. Patients with RF had a significant increase in adverse clinical outcome compared to stone-free subjects, with an odds ratio of 3.9 (95% CI 1.5-9.6). The presence of metabolic disorders was associated with RF growth (odds ratio 11.4, 95% CI 1.5-79).
  
  
  CONCLUSIONS
  Small RF after ESWL is clinically significant in children and increase the chance of adverse clinical outcome. These patients require close followup, particularly those with identifiable predisposing disorders.
authors.affiliation: Division of Urology, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Kourosh
authors.initials: K
authors.lastname: Afshar
authors.forename: Gordon
authors.initials: G
authors.lastname: McLorie
authors.forename: Frank
authors.initials: F
authors.lastname: Papanikolaou
authors.forename: Rowja
authors.initials: R
authors.lastname: Malek
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Harvey
authors.forename: Joao L
authors.initials: JL
authors.lastname: Pippi-Salle
authors.forename: Darius J
authors.initials: DJ
authors.lastname: Bagli
authors.forename: Antoine E
authors.initials: AE
authors.lastname: Khoury
authors.forename: Walid
authors.initials: W
authors.lastname: Farhat
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007669:Kidney Calculi / Q000473:pathology / Q000628:therapy*; D008096:Lithotripsy; D008297:Male; D016896:Treatment Outcome