title: Comparison of children versus adults undergoing mini-percutaneous nephrolithotomy: large-scale analysis of a single institution.
abstract: OBJECTIVE
  As almost any version of percutaneous nephrolithotomy (PCNL) was safely and efficiently applied for adults as well as children without age being a limiting risk factor, the aim of the study was to compare the different characteristics as well as the efficacy, outcome, and safety of the pediatric and adult patients who had undergone mini-PCNL (MPCNL) in a single institution.
  
  
  METHODS
  We retrospective reviewed 331 renal units in children and 8537 renal units in adults that had undergone MPCNL for upper urinary tract stones between the years of 2000-2012. The safety, efficacy, and outcome were analyzed and compared.
  
  
  RESULTS
  The children had a smaller stone size (2.3 vs. 3.1 cm) but had smilar stone distribution (number and locations). The children required fewer percutaneous accesses, smaller nephrostomy tract, shorter operative time and less hemoglobin drop. The children also had higher initial stone free rate (SFR) (80.4% vs. 78.6%) after single session of MPCNL (p<0.05); but no difference was noted in the final SFR (94.7% vs. 93.5%) after auxiliary procedures. The complication rate (15.6% vs. 16.3%) and blood transfusion rate (3.1% vs. 2.9%) were similar in both group (p>0.05). Both groups had low rate of high grade Clavien complications. There was no grade III, IV, V complications and no angiographic embolization required in pediatric group. One important caveat, children who required multiple percutaneous nephrostomy tracts had significant higher transfusion rate than in adults (18.8% vs. 4.5%, p = 0.007).
  
  
  CONCLUSIONS
  This contemporary largest-scale analysis confirms that the stone-free rate in pediatric patients is at least as good as in adults without an increase of complication rates. However, multiple percutaneous nephrostomy tracts should be practiced with caution in children.
authors.affiliation: Department of Urology, Minimally Invasive Surgery Center, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. gzgyzgh@vip.tom.com
authors.forename: Guohua
authors.initials: G
authors.lastname: Zeng
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Zhao
authors.forename: ShawPong
authors.initials: S
authors.lastname: Wan
authors.forename: Wen
authors.initials: W
authors.lastname: Zhong
authors.forename: Wenqi
authors.initials: W
authors.lastname: Wu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003710:Demography; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology; D055815:Young Adult