title: Urolithiasis in the low birth weight infant: the role and efficacy of extracorporeal shock wave lithotripsy.
abstract: OBJECTIVE
  Nephrolithiasis in preterm infants rarely requires surgical management. When it persists despite conservative therapy, treatment options are not clearly defined. We report a single institutional experience with extracorporeal shock wave lithotripsy (ESWL)* for the treatment of these small infants.
  
  
  METHODS
  We treated 8 infants (mean age 13 months) with a history of prematurity and 9 persistent stones with a Dornier HM3 lithotriptor between 1996 and 1999. Mean weight was 7,700 gm. Of the infants 7 had been treated with furosemide for bronchopulmonary dysplasia and 1 presented with multiple anatomical abnormalities. Gantry modification with a wooden platform and polystyrene foam positioning was used for lung and visceral protection. Ureteral stents were placed in 5 patients before ESWL. Renal ultrasonography was performed before, and 2 and a mean of 8 weeks after ESWL. Stone risk factors in our population were investigated through a multispecialty approach.
  
  
  RESULTS
  Average stone burden was 47.9 mm.2. A total of 9 sessions of ESWL were required for complete fragmentation of the 9 renal stones. A mean total of 2,100 shocks at a mean 16.1 kV. were administered. One patient with bilateral stones was treated in 2 separate sessions after a 4-week interval. No repeat ESWL sessions or other surgical interventions were required in any patient. Renal ultrasonography demonstrated no post-ESWL morphological changes. Practices leading to a higher incidence of neonatal nephrolithiasis at our institution were also identified.
  
  
  CONCLUSIONS
  ESWL is effective treatment for nephrolithiasis in small infants. Short-term safety has been established but continued long-term functional followup is essential. Multifactorial etiologies of nephrolithiasis must be identified and modified promptly in the care of preterm infants.
authors.affiliation: Children's Urology Group and Division of Urology, University of South Florida, Tampa, Florida, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: Shukla
authors.forename: D L
authors.initials: DL
authors.lastname: Hoover
authors.forename: Y L
authors.initials: YL
authors.lastname: Homsy
authors.forename: S
authors.initials: S
authors.lastname: Perlman
authors.forename: S
authors.initials: S
authors.lastname: Schurman
authors.forename: E M
authors.initials: EM
authors.lastname: Reisman
mesh_terms: D006801:Humans; D007223:Infant; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000628:therapy*; D008096:Lithotripsy; D012307:Risk Factors; D014545:Urinary Calculi / Q000453:epidemiology / Q000628:therapy*