title: Time to development of symptomatic urinary calculi in a high risk environment.
abstract: OBJECTIVE
  While seasonal variation of stone disease is well described, the time to formation of urinary calculi is unknown. Because southwestern Asia is a high risk environment for stone disease, the date of entry into this region is a definitive beginning to a period of increased risk of urinary calculi. The recent influx of Department of Defense personnel into southwestern Asia provided the opportunity to observe stone disease in a cohort of healthy personnel during a well-defined period of increased risk of stone formation.
  
  
  METHODS
  A database was constructed for all patients presenting with symptomatic urinary calculi to a single military hospital deployed to Kuwait from March through August 2003. Patient demographics, stone characteristics and time to formation of symptomatic urinary calculi were evaluated.
  
  
  RESULTS
  A total of 182 patients were diagnosed with 218 symptomatic stones. Mean time to formation of symptomatic urinary calculi was 93 days with a standard deviation of 42 days.
  
  
  CONCLUSIONS
  This study provides unprecedented information about the development of symptomatic urinary calculi in a high risk environment. While unique aspects of the population, environment and medical system created a singular opportunity to study stone disease, the results of this study are applicable to the general population.
authors.affiliation: 47th Combat Support Hospital, Fort Lewis, Washington, USA. karen.evans@amedd.army.mil
authors.forename: Karen
authors.initials: K
authors.lastname: Evans
authors.forename: Raymond A
authors.initials: RA
authors.lastname: Costabile
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000453:epidemiology* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D011446:Prospective Studies; D012307:Risk Factors; D013997:Time Factors; D014514:Ureteral Calculi / Q000453:epidemiology* / Q000209:etiology*