title: The natural history of asymptomatic urolithiasis.
abstract: An inception cohort of 107 patients was reviewed to establish the natural history of asymptomatic urolithiasis. With an over-all mean followup of 31.6 months, 73 patients (68.2%) remained asymptomatic and were censored at the time of the last clinical visit. A symptomatic event developed in 34 patients (31.8%). Spontaneous passage occurred in 16 patients (15.0%), endoureteral removal was done in 6 (5.6%), percutaneous nephrostolithotomy was done in 3 (2.8%) and 9 (8.4%) were referred for therapeutic lithotripsy. Cumulative 5-year probability of a symptomatic event developing was 48.5%. A linear association was identified between the development of a symptomatic event and the number of previous stones as well as the number of asymptomatic stones at identification. A significant burden of illness is associated with an expectant strategy as an approach to asymptomatic urolithiasis. Of the patients who had a symptomatic event 47% had spontaneous stone passage, while 26.5% required urological intervention and 26.5% were referred for therapeutic lithotripsy. Prophylactic extracorporeal shock wave lithotripsy, although often advocated, has associated risks and is not always a benign procedure. A randomized controlled trial is required to evaluate properly the role of prophylactic lithotripsy versus an expectant strategy.
authors.affiliation: Department of Medicine, St. Joseph's Hospital, Hamilton, Ontario, Canada.
authors.forename: L S
authors.initials: LS
authors.lastname: Glowacki
authors.forename: M L
authors.initials: ML
authors.lastname: Beecroft
authors.forename: R J
authors.initials: RJ
authors.lastname: Cook
authors.forename: D
authors.initials: D
authors.lastname: Pahl
authors.forename: D N
authors.initials: DN
authors.lastname: Churchill
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012306:Risk; D014545:Urinary Calculi / Q000737:chemistry / Q000175:diagnosis* / Q000628:therapy