One in every 11 people develops a renal stone at some point in their life.1 Although nephrolithiasis may occur at any age, onset is more common in young and middle-aged adults. Lifetime prevalence is estimated at 13 percent for men and 7 percent for women. Following an initial stone event, the spontaneous 5-year recurrence rate is 35 to 50 percent.
Nephrolithiasis often is incidentally identified in asymptomatic patients who undergo plain radiographs or computed tomographic imaging for another indication.5 Small stones generally pass through the urinary tract without symptoms. While larger stones may cause symptoms, more than 90 percent of stones less than 5 mm in diameter still pass through the urinary tract without intervention, as compared to spontaneous passage of approximately 50 percent of stones 5 to 10 mm in diameter.